Ứng Dụng Laser Trong Da Liễu Và Y Học (2018)

34
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A. A. Lloyd et al.

37
© Springer International Publishing AG, part of Springer Nature 2018
K. Nouri (ed.), Lasers in Dermatology and Medicine,
Laser Safety: Regulations,
Standards and Practice Guidelines
Brienne D. Cressey, Ashley Keyes,
and Murad Alam
Abstract
The use of lasers is routine in many medical
specialties. In some cases, the particular ben-
efit of lasers has made them desirable alterna-
tives to conventional surgical instruments
such as scalpels, electrosurgical units, cryo-
surgery probes, or microwave devices.
Keywords
Laser · Laser safety · Laser regulations
Laser standards · Laser guidelines
Dermatologic lasers · Medical lasers
Laser Safety
The use of lasers is routine in many medical spe-
cialties. In some cases, the particular benefit of
lasers has made them desirable alternatives to con-
ventional surgical instruments such as scalpels,
electrosurgical units, cryosurgery probes, or micro-
wave devices. The American Society for Laser
Medicine and Surgery (ASLMS) outlines several
advantages of laser use in clinical practice [1]:
Lasers allow the surgeon to accomplish more com-
plex tasks, reduce blood loss, decrease postopera-
tive discomfort, reduce the chance of wound
infection, decrease the spread of some cancers,
minimize the extent of surgery in selected circum-
stances and result in better wound healing, if used
appropriately by a skilled and properly trained
surgeon.
Despite these benefits, when misused, lasers
can injure both patients and operator. To ensure
safety and quality care, guidelines for laser safety
have been developed.
B. D. Cressey
Department of Dermatology, New York Presbyterian-­
Weill Cornell Hospital, New York, NY, USA
A. Keyes (*)
Department of Dermatology, Weill Cornell Medicine,
Lincoln Medical Center, Bronx, NY, USA
e-mail: Ashley.keyes@nychhc.org
M. Alam
Section of Cutaneous and Aesthetic Surgery,
Department of Dermatology, Otolaryngology-Head
and Neck Surgery, and Surgery, Feinberg School of
Medicine, Northwestern University,
Chicago, IL, USA
e-mail: m-alam@northwestern.edu
2

38
Governing Bodies and Professional
Organizations
A number of regulatory and professional
organizations have promulgated and dissemi-
nated recommendations for safe laser use.
Though there is considerable agreement among
professional organizations and regulatory
agencies regarding laser safety guidelines,
variation among patients, facilities, and state
laws ultimately affects how these rules are
implemented.
The American National Standards Institute
(ANSI) creates and publishes consensus stan-
dards for the conduct of business in almost all
sectors, including medicine. This chapter will
refer to the ANSI Z 136.3, the American National
Standard for Safe Use of Lasers in Health Care
Facilities, with specific attention to control mea-
sures, as it is widely regarded as the standard for
laser use. It is important to clarify that these stan-
dards are recommended practices rather than
rules subject to enforcement, and compliance is
both voluntary and dependent on individual orga-
nization’s specifications.
In addition to the standards set forth by ANSI,
medical organizations also set professional stan-
dards for their membership. The American
Society for Laser Medicine and Surgery
(ASLMS), with its multidisciplinary member-
ship, including physicians and surgeons, nurses,
and other health professionals, is an umbrella
organization for all specialties whose clinical
care involves lasers. In addition to formulating
standards and guidelines for implementing safe
and effective laser practices, ASLMS also makes
recommendations to medical laser training pro-
grams regarding procedural skills for individuals
operating lasers.
The American Academy of Dermatology
(AAD), the primary professional organization for
practicing dermatologists in the United States,
encourages the safe practice of medicine and
acknowledges that medical laser is subsumed
under the practice of medicine. “The Academy
endorses the concept that use of properly trained
non-physician office personnel under appropriate
supervision allows certain procedures to be per-
formed safely and effectively” [2].
The American Society for Dermatologic
Surgery (ASDS), the main professional organiza-
tion within dermatology for proceduralists, is
committed to the development of safe in-office
procedures. The ASDS maintains that medical
laser use constitutes the practice of medicine, and
that non-physicians should use lasers only when
delegated do so by physicians who are appropri-
ately supervising them.
Medical laser use is also subject to regulation
by the relevant state and by the U.S. Food and
Drug Administration (FDA). Laser devices, such
as those used for medical application require
clearance or premarket approval by the FDA
Center for Devices and Radiological Health
(CDRH) prior to distribution for commercial use
in the United States. The Radiation Control for
Health and Safety Act (RCHSA), a standard sim-
ilar to that of ANSI, is intended to prevent unnec-
essary or inappropriate access to laser equipment,
and to minimize exposure to collateral radiation.
Additionally, RCHSA ensures the appropriate
performance features and labels are provided by
the manufacturer [2]. With respect to laser
devices, the FDA is responsible for classifying
laser devices based on levels of laser emission.
For medical use, lasers are defined as Class III
and IV, which require the highest level of regula-
tion for safe use.
Many regulatory and professional organi-
zations provide recommendations and
guidelines for laser safety. While the
American National Standards Institute
(ANSI) publishes consensus standards
considered to be the standard in laser
safety, these standards are recommended
practices only. The positions of profes-
sional organizations are important to con-
sider in addition to those of ANSI to ensure
comprehensive safety standards for laser
use are practiced.
B. D. Cressey et al.

39
Practice Guidelines
Procedural Skills
The ASLMS outlines recommendations for the
safe use of laser technology, specifically training
and credentialing benchmarks, to be used in con-
junction with the ANSI Z 136.3 guidelines.
Training and credentialing represent distinct issues
for laser safety, especially given the escalating
debate regarding laser use by non-physicians.
The ANSI Z 136.3 refers to the ASLMS pol-
icy “Standards of Training for Physicians for the
Use of Lasers in Medicine and Surgery”, which
was approved by the board of directors on April
3 of 2008, regarding the recommendation for
appropriate training for laser privileges. The spe-
cific suggestions for training are as follows [3]:
The initial program should include clinical applica-
tions of various wavelengths in the particular specialty
field and hands-on practical sessions with lasers and
their appropriate surgical or therapeutic delivery sys-
tems. A minimum of 8–10 hours is suggested by the
ANSI standards. A further 40% of the time should be
allocated to the practical sessions. However, more
time may be required to complete the basic course
contents. Usually, basic training is concentrated on
one or more wavelengths. Subsequent programs cov-
ering different wavelengths or substantially different
applications or delivery instruments may require more
hours of training of which 50% of the time is allocated
to hands-on sessions. A small faculty-student ratio in
the range of 1 to 3-5 is optimal.
It is recommended that an applicant for privi-
leges spend time after the basic training course in a
clinical setting with an experienced operator (such
programs are often called “preceptorship” training
programs or “observation”) when appropriate and
practical. Several brief visits or a more prolonged
period suffices provided that a variety of cases is
observed. It is valuable for the novice to perform
the laser procedures with supervision by the expert,
however, for a variety of reasons, such as hospital
privileges, status of patients and insurance cover-
age of physicians, this is not always possible.
In addition to training recommendations for
physicians, ANSI also suggests standards for gen-
eral laser safety and training programs, with specific
attention to nurses and other non-­medical person-
nel. The following summarizes this position [3]:
Laser safety training for perioperative nursing and
support personnel must be compatible with that
taught to physicians. A smoothly functioning laser
team depends on this, and every effort must be
made to eliminate any discrepancies in training
materials. Content of this program should stress
overall understanding of operation characteristics
of equipment, biologic and physical properties of
the laser tissue interaction, potential hazards asso-
ciated with laser use, and procedures and equip-
ment required to ensure a safe laser environment.
ANSI maintains that training in laser safety
practices for physicians and non-physicians
should be distinguished from training of methods
and techniques of laser procedures.
Though the need for operators to be trained
in laser use is universally accepted, the process
of credentialing physician and/or non-physician
operators as competent in laser use is more sub-
ject to debate and interpretation. Often strict
and multiple criteria must be simultaneously
met to satisfy credentialing rules. In its paper
entitled “Procedural Skills for Using Lasers in
General Surgery,” which was revised on August
2, 2012 by the ASLMS board of directors, the
criteria for granting laser privileges are summa-
rized [4]:

A. The physician (attending) must be a diplo-
mat of or be admissible to a specialty
Board such as the American Board of
Surgery; Orthopedics; Otolaryngology;
Ophthalmology; Urology; Dermatology;
Plastic Surgery; Cardiovascular Surgery;
Neurosurgery; or other medical specialty.

B. The physician must first have been granted
appropriate privileges by the facility
through the designated certification and
facility process. The physician must have
privileges to perform requested procedures
in the absence of laser use.
The first tenet to laser safety is the training
of physicians, healthcare professionals,
and personnel. The American Society for
Laser Medicine and Surgery (ASLMS)
outlines recommendations for training and
credentialing, which are referenced by the
ANSI standards
2  Laser Safety: Regulations, Standards and Practice Guidelines

40

C. The physician must have been trained to use
laser(s) in a recognized and approved resi-
dency program or must have obtained train-
ing through an appropriate CME course.

D. Physicians using a laser adapted to an oper-
ating microscope or other optical device
must demonstrate proficiency in the use of
the optical equipment in addition to the
laser technology. The physician must
already have hospital privileges for the use
of these instruments in the performance of
procedures with conventional techniques.

E. The user of the laser must be cognizant of
the safety hazards of lasers. This knowledge
must be obtained either through a residency
program or an appropriate CME course.
Proof of this training must be supplied in
writing to the Laser Usage Committee at
the time privileges are requested.

F. Initial approval or use of laser will be provi-
sional until the physician has demonstrated
the ability to use lasers to a member of the
Medical Staff who has been designated by
the facility as being qualified and must have
achieved the required standards as previ-
ously listed. The criteria for recertification
shall be set forth and a yearly review of cases
and their outcomes shall be performed.

G. If the applicant requests the use of the laser
for investigational purposes, the request
must receive approval by the facility’s
Clinical Investigation Committee (IRB/
CIC) as is required for all other research
purposes. An appropriate investigational
protocol and informed consent process
must be in place.

H. Residents involved in the use of lasers may
not perform procedures with these instru-
ments until such time as they have attended
an in-depth training program or an appro-
priate CME course recognized to be ade-
quate by the Laser Usage Committee. In
addition, residents must be supervised by a
laser-certified attending physician during
actual utilization of laser technology at all
times.
Similarly, ASLMS outlines physician qualifica-
tions for proficiency in laser techniques in its policy
statement entitled “Procedural Skill and Technique
Proficiency for Surgery and Other Energy-Based
Therapies in Dermatology”. Approved and revised
on August 2, 2012, by the board of directors, the
following requirements are relevant to laser use in
dermatology [5].
•
Possession of an appropriate medical degree or
its equivalent. Candidates must be a Doctor of
Medicine (MD) or Doctor of Osteopathy (DO)
and complete an ACGME accredited residency
in their specialty areas.
•
Must possess primary specialty certification
from the American Board of Dermatology.
•
For a specified period of time (5 years) there
will be a practice category for eligibility.
Specific criteria for qualifying under this cate-
gory will be determined and approved by an
independent
certifying
body.
Suggested
requirements for this category may include the
following:
a) Completion of at least 150 hours of Category 1
CME including laser safety and physics. At least
20 hours of the 150 hours must entail hands on
workshops proctored by an experienced physi-
cian in laser medicine and surgery and a mini-
mum of 50 hours in programming approved by
the American Society for Laser Medicine and
Surgery (ASLMS), American Academy of
Dermatology (AAD) or the American Society
for Dermatological Surgery (ASDS).
b) Submission of 100 cases with a minimum of
15 sets of before and after photos or video-
tapes representative of at least 4 of the 9 man-
agement areas.
c) Mastery of Standards of Training must be
demonstrated by obtaining a passing grade on
an examination the content of which will be
determined by an independent certifying body.
d) Letters of recommendation attesting to char-
acter from at least three practicing physicians
in the same specialty.
It is the widely accepted belief of the aforemen-
tioned organizations that a necessary precondition for
patient safety is the proper training and credentialing
of healthcare professionals. As such, despite differ-
ences in details, there is minimal, significant varia-
tion in the standards by which physicians are assessed
with regard to their competence to utilize medical
laser devices. Discrepancies arise when considering
credentialing of alternative allied health providers,
which will be addressed later in this chapter in the
section on delegation and regulation by the state.
B. D. Cressey et al.

41
Administrative Controls
The ANSI Z 136.3 is accepted as the standard
for guidelines regarding the safe use of laser in
health care facilities. Specifically, this document
details control measures to minimize the poten-
tial hazards of laser use. Though each facility and
patient engenders unique safety considerations,
the following guidelines address unintended haz-
ards to both patients and personnel.
To ensure administrative control within the
health care facility, a Laser Safety Officer (LSO)
is appointed to implement the following stan-
dards [3].
4.2.1 Policies and Procedures (Class 3B and Class 4).
The health care facility (HCF) shall establish policies
and procedures (P&Ps). The P&Ps should include, for
example, perioperative checklists for use by operating
personnel. The LSO shall require approved written
operating and maintenance P&Ps for Class 3B and
Class 4 Hospital Care Laser Systems (HCLS). These
operating and maintenance P&Ps shall be maintained
and readily available. The LSO shall require that
safety SOPs exist for servicing of the HCLS.
4.2.3 Authorized Personnel-Laser Users. Class 3B
and Class 4 HCLSs shall be operated by facility-­
authorized personnel appropriately trained in the
safe use of the HCLS.
4.2.5 Procedural Controls. Procedural controls, as
determined, by the LSO, shall be used where pos-
sible to avoid potential hazards associated with
Class 3B and Class 4 HCLSs. These include con-
trols such as:
(1) Adhering to written P&Ps
(2) Assigning a dedicated person to operate the controls,
if applicable, when appropriate for the procedure and
practice setting.
(3) Maintaining a list of authorized laser users and Health
Care Personnel (HCP)
(4) Requiring storage or disabling (removal of key) of the
HCLS where unauthorized operation is of concern.
(5) Assuring that operators know the location and opera-
tion of the emergency stop control provided with each
HCLS.
(6) Assuring that the ready function is enabled only when
the user is ready to treat the target tissue.
(7) Using of only diffuse reflective materials or instru-
ments with low reflectance in or near the beam path,
where feasible.
(8) Taking steps to avoid confusion encountered during
surgical procedures when operating with more than
one floor pedal.
The specific administrative controls imple-
mented in a health care facility may vary. It is
the LSO’s responsibility to ensure the appropri-
ate safety measures are in place to accommo-
date the specific needs of the patient and
facility.
Figure 2.1 illustrates an overview of practice
guidelines and to whom they are relevant.
Protective Equipment
Warning Signs and Labels
The Nominal Hazard Zone (NHZ) is the physical
space in which levels of radiation, direct,
reflected, or scattered, exceed the Maximum
Permissible Exposure (MPE), which may be
determined by the safety information provided
Administrative controls are essential for
the safe operation of lasers within a health-
care facility. These control measures mini-
mize the potential for hazards to operator
and patient during laser use. A Laser Safety
Officer (LSO) is appointed to ensure the
appropriate standards are followed.
Protective equipment includes warning
signs and labels, eye and skin protection,
and smoke evacuation systems to reduce
non-beam hazards. Used properly during
laser procedures, protective equipment
reduces the risk of injury to operator and
patient, as well as increases the overall
safety of healthcare facilities in which laser
equipment resides.
2  Laser Safety: Regulations, Standards and Practice Guidelines

42
by the manufacturer. While a Class III or Class
IV laser is in operation, appropriate warning
signs and labels, as well as protective equipment
is administratively required for all individuals
within the NHZ. Warning signs and labels are
provided by the ANSI Z 136.3 in accordance with
the Federal Laser Product Performance Standard,
including the following [3]:
4.7.1 Display of Warning Signs. Warning signs
shall be conspicuously displayed on all doors
entering the Laser Treatment Controlled Area
(LTCA), so as to warn those entering the area of
laser use. Warning signs should be covered or
removed when the laser is not in use.
4.7.3 Inclusion of Pertinent Information. Signs and
Labels
shall
conform
to
the
following
specifications.
4.7.3.1 The appropriate signal word (Caution or
Danger) shall be located in the upper panel.
4.7.3.2 Adequate space shall be left on all signs
and labels to allow the inclusion of pertinent infor-
mation. Such information may be included during
the printing of the sign or label or may be hand-
written in a legible manner, and shall include the
following.
(1) At position 1 above the tail of the sunburst, special
precautionary instructions or protection action such
as “Laser Surgery in Process—Eye Protection
Required”
a. For Class 2 lasers and laser systems, “Laser
Radiation—Do Not Stare into Beam”
b. For Class 3 lasers and laser systems where
the accessible irradiance does not exceed
the appropriate MPE based on a 0.25 s
exposure, “Laser Radiation—Do Not Stare
into Beam or View with Optical Instruments”
c. For all other Class 3R lasers and laser sys-
tems, “Laser Radiation—Avoid Direct
Exposure to Beam”
d. For all Class 3B lasers and laser systems,
“Laser Radiation—Avoid Direct Exposure
to Beam”
e. For Class 4 laser and laser systems, “Laser
Radiation—Avoid Eye or Skin Exposure to
Direct or Scattered Radiation”
(2) At position 1 above the tail of the sunburst, special pre-
cautionary instructions or protective action such as:
“Laser Surgery in Process—Eye Protection Required”
(3) At position 2 below the tail of the sunburst, type of
laser (Nd: YAG, CO2, etc.) or the emitted wavelength,
pulse duration (if appropriate), and maximum
output.
(4) At position 3, the class of the laser or laser system.
Figure 2.2 shows the appropriate warning signs
for (a) Class 2 lasers and (b) Class 3 and 4 lasers.
Administrative Controls
The Laser
Training Program
Allied
Health Professional
LSO
Physician
Responsible
for the safe
and effective
performance
of laser
procedures
Responsible
for
understanding
the standards
and
administrative
infrastructure
Responsible
for the laser
safety
program in
the health
care facility
Perioperative Safety
Fig. 2.1  Three key
components of a laser
safety program include
understanding of
administrative controls,
knowledge of laser
function and use, and
guidelines for
perioperative safety.
Despite variation in
responsibilities among
physicians, healthcare
professionals and the
LSO, consensus among
practice guidelines is
essential to the safe use
of medical lasers
B. D. Cressey et al.

43
Eye and Skin Protection
Additional protective measures must be followed
to ensure the safety of patients, staff, and opera-
tor while in the NHZ. The following recommen-
dations are relevant to eye and skin safety [3]:
4.6.2 Laser Protective Eyewear (Class 3B and
Class 4). Laser protective eyewear may include but
not be limited to goggles, face shields, spectacles
or prescription eyewear using special filter materi-
als or reflective coatings (or a combination of
both), which are selected to reduce the potential
ocular exposure below the applicable MPE level.
Eyewear shall be accompanied by the following
information:
(1) Optical density at appropriate wavelengths.
(2) Manufacturer’s recommendations on shelf life,
storage conditions, and appropriate cleaning
methods.
4.6.2.4 Cleaning and Inspection. Periodic cleaning
and inspection of protective eyewear shall be made
to ensure the maintenance of satisfactory condition.
The lenses should be cleaned carefully to avoid
damage to the absorbing and reflecting surfaces.
This shall include:
(1) Inspection of the attenuation material for pitting,
crazing, cracking, discoloration, etc.
(2) Inspection of the frame for mechanical integrity.
(3) Inspection of straps or other retaining devices to
ensure that they are not excessively worn or
damaged.
(4) Inspection for light leaks and coating damage that
would permit hazardous intrabeam viewing.
4.6.3 Laser Protective Barriers and Curtains (Class
3B and Class 4). Facility windows (exterior or inte-
rior) or entry ways that are located within the NHZ
of a Class 3B or Class 4 laser system, shall be pro-
vided with an appropriate filter or barrier which
reduces any transmissible radiation to levels below
the applicable MPE level.
4.6.3.1 Drapes. Use only wet or nonflammable
drapes in the operative field.
4.6.4 Skin Protection (Class 3B and Class 4). The
manufacturer of the HCLS or the LSO shall spec-
ify the appropriate laser protective equipment by
make and model or performance specifications
and the locations and conditions for use of the
skin protective equipment. Skin protection shall
be used whenever there is a potential hazard to
HCP.
Though protective equipment is required for
all individuals within the NHZ, depending on the
nature of the procedure, the protocol for patient
eye protection may be different for operator and
staff protection. The following specifications are
important to consider, especially for procedures
performed on the face:
4.4.4 Patient Eye Protection. When the patient’s
eyes are potentially within the NHZ, they shall be
protected from inadvertent exposure by a method
approved by the LSO. The suitability of patient eye
protection methods and equipment shall be deter-
mined based on the intended procedure, target
­tissue site, wavelength and delivery system of the
HCLS, positioning of the patient, and type of
anesthesia.
When facial areas, particularly around the eyes
are being treated, e.g., for port wine stains or neo-
plasia, protective glasses may not be appropriate
a
b
POSITION 1
BOLD BLACK LETTERING
POSITION 1
BOLD BLACK LETTERING
POSITION 2
BOLD BLACK LETTERING
POSITION 2
BOLD BLACK LETTERING
POSITION 3
BLACK LETTERING
POSITION 3
BLACK LETTERING
Fig. 2.2  The distinction between appropriate laser warning signs for (a) Class 2 and (b) Class 3 and 4 lasers
2  Laser Safety: Regulations, Standards and Practice Guidelines

44
for shielding the eyes. For treatments on or near the
eyelids, appropriate corneal shields are usually
required, and the shield shall have appropriate
optical properties to reduce exposure below the
applicable MPE. Additionally, patient eye protec-
tion is not intended to restrict or limit in any way
the use of laser radiation intentionally adminis-
tered for therapeutic or diagnostic purposes.
There is a consensus among professional
organizations that laser protective equipment
should not only be in good working order, but
also meet both local and ANSI standards for pro-
tective equipment. Figure 2.3 shows a variety of
eye protection for both patient and operator.
Non-beam Hazards
Besides direct hazards to the eyes and skin due to
laser beam exposure, concerns associated with
non-beam hazards present unique laser safety
considerations. According to a publication by the
National Institute for Occupational Safety and
Health (NIOSH), the plume (smoke byproduct)
produced by thermal destruction of tissue can
contain toxic gases or vapors, dead or living cel-
lular material, or even viruses. As a result, control
of smoke is essential to minimize health risks to
health care personnel, as well as visual interfer-
ence to the individual performing the procedure.
NIOSH recommends the two following methods
of ventilation for the management of airborne
contaminants [6]:
Smoke evacuators contain a suction unit (vacuum
pump), filter, hose, and an inlet nozzle. The smoke
evacuator should have high efficiency in airborne
particle reduction and should be used in accor-
dance with the manufacturer’s recommendations
to achieve maximum efficiency. A capture velocity
of about 100 to 150 feet per minute at the inlet
nozzle is generally recommended. It is also impor-
tant to choose a filter that is effective in collecting
the contaminants. A High Efficiency Particulate
Air (HEPA) filter or equivalent is recommended
for trapping particulates. Various filtering and
cleaning processes also exist which remove or
inactivate airborne gases and vapors. The various
filters and absorbers used in smoke evacuators
require monitoring and replacement on a regular
basis and are considered a possible biohazard
requiring proper disposal.
Room suction systems can pull at a much lower
rate and were designed primarily to capture liquids
rather than particulate or gases. If these systems
are used to capture generated smoke, users must
install appropriate filters in the line, ensure that the
line is cleared, and that filters are disposed prop-
erly. Generally speaking, the use of smoke evacua-
tors is more effective than room suction systems to
control the generated smoke from nonendoscopic
laser/electric surgical procedures.
In a statement entitled “Smoking Guns”,
approved by the Board of Directors of the
ASLMS, the aforementioned NIOSH guidelines
are referenced; however, the statement highlights
that these guidelines stop short of requiring per-
sonal respirators for personnel within the operat-
ing room. The ANSI Z 136.3 states that currently
a suitable half-mask respirator (fitting over the
nose and mouth) to exclude laser-generated
plume does not exist. As such, the recommenda-
tion is that health care facilities rely on appropri-
ate ventilation techniques to protect against laser
generated airborne contaminants [3]. It is the
unanimous opinion of the aforementioned
­regulatory organizations that a smoke evacuation
apparatus be utilized to protect patient and per-
sonnel and to control smoke levels in the operat-
ing room.
Fig. 2.3  A selection of
eyewear suitable for
patient and operator
safety. Care should be
taken to select the
appropriate lenses to
protect against various
levels of laser emission
B. D. Cressey et al.

45
Delegation of Use of Lasers
In recent years, there has been increasing con-
cern regarding frequency and severity of reported
adverse events associated with the use of lasers
by non-physicians. This has led to calls for
increased regulation regarding delegation of
medical procedures to non-physicians. Guidelines
have been created by professional organizations
as well as state medical boards and legislature to
delineate who is qualified to safely practice med-
icine involving lasers.
The ASDS and AAD maintain the position that
only active and properly licensed doctors of medi-
cine and osteopathy shall conduct the practice of
medicine. But, a physician may delegate certain
medical procedures to certified or licensed allied
health professionals under the appropriate circum-
stances. The ASDS Board of Directors approved
the following statement in May of 2008 [7].
The physician must directly supervise the allied
health professionals to protect the best interests
and welfare of each patient. The supervising physi-
cian shall be physically present on-site, immedi-
ately available, and able to respond promptly to
any question or problem that may occur while the
procedure is being performed. It is the responsible
physician’s obligation to ensure that, with respect
to each procedure performed, the allied health pro-
fessionals possess knowledge of cutaneous medi-
cine, documented training in the procedure, the
indications for the procedure, and the pre- and
post-operative care involved.
In a position statement approved by the
Board of Directors on February 22, 2002, the
AAD expressed a similar opinion regarding
medical laser use by non-physicians with an
additional requirement: “The non-physician
office personnel should also be appropriately
trained by the delegating physician in cutaneous
medicine” [2].
Though the positions of the ASDS and AAD
appear clear, delegation remains a controver-
sial issue, especially due to the potential ambi-
guity that arises from differences in state
legislation.
In addition to adhering to the standards set
forth by their professional organization, physi-
cians must comply with state laws regarding laser
use. In this chapter, legislation in California,
Florida, Illinois, New  York, and Texas will be
addressed. The Federation of State Medical
Boards last summarized the following regula-
tions for each state in May 2012.
In California, laser regulation adheres
closely to the position of the ASDS, with addi-
tional stipulations regarding written documen-
tation of supervision protocols and procedures.
California also defines which non-physician
health professionals may perform laser hair
removal [8]:
The Business and Professions Code includes the
use of laser devices in the definition of the practice
of medicine. Only physicians, dentists, physician
assistants and nurses may use laser devices, includ-
ing intense pulse light devices, with physician
supervision within their legal scope of practice.
The law requires written protocols and procedures
relating to supervision. Laser hair removal may be
performed only by a nurse physician or, when
working with a physician, registered nurse or phy-
sician assistants.
In Florida, however, specifications requiring
registration of laser systems with the Department
of Health set an additional standard for safety [8].
The Board of medicine considers the use of high-­
powered lasers (all Class IIIa, IIIb, and IV lasers as
designated by the FDA) to be the practice of medi-
cine. These may be used only by physicians, or by
those exempt from the Medical Practice Act (such
as nurses) while acting under the direct supervision
of a physician. Florida also requires all high-­
powered laser systems to be registered with the
Non-physician use of lasers has been sub-
ject to debate in recent years leading to
calls for increased regulation regarding
delegation of medical procedures to alter-
native healthcare professionals. While pro-
fessional organizations maintain their own
positions on delegation of medical proce-
dures, state legislature plays a significant
role in this determination as well.
Regardless of the differences between
organizations and states, the consensus is
that the physician is ultimately responsible
for patient safety.
2  Laser Safety: Regulations, Standards and Practice Guidelines

46
Department of Health. Failure to do so may be
grounds for disciplinary action against a physician
and may result in a criminal penalty.
Additionally, Florida mandates specialty-­
specific requirements relating to supervision [8].
In office setting where supervision not onsite, pri-
mary health practitioners limited to supervising 4
offices in addition to the primary office location;
specialty practitioners limited to 2; dermatologists
limited to 1.
In Illinois, the state legislature issued the fol-
lowing statement regarding the use of lasers for
non-physician users:
“Laser equipment, which affects living layers of
skin, is a medical device and must only be used
with the direct supervision by a physician. While
the physician may delegate performance of laser
procedures to appropriately educated, trained, and
experienced nurses or other personnel, the physi-
cian must provide proper supervision, including
initial assessment, on-site availability and ultimate
responsibility.”
The Board of Medicine in New York regulates
the use of lasers for hair removal in a similar
manner as California and Illinois [8]:
In August 2002, the NY State Board of Medicine
passed a resolution recommending that the use of
lasers and intense pulsed light for hair removal to
be considered the practice of medicine and thus be
performed by a physician or under direct physician
supervision.
To ensure compliance with these regulations,
the New York Education Law defines the follow-
ing two statutes as professional misconduct [8]:
24) Practicing beyond the scope of practice permit-
ted by state law and performing professional
responsibilities a licensee knows he/she is not
competent to perform.
25) Delegating professional responsibilities to a
person when the licensee delegating such responsi-
bilities knows or has reason to know that such per-
son is not qualified, by training, experience or by
licensure to perform.
Though New York law does not address new
issues, it strengthens the responsibility of the phy-
sician by including regulations on delegation
prominently within its code of professional
misconduct.
In Texas, the State Board provides a few
detailed clarifications the previous states do not.
In the position statements on laser regulation, on-­
site supervision is defined as continuous supervi-
sion with the individual in the same building [8].
Further, the State Board explicitly distinguishes
practice guidelines for ablative and non-ablative
procedures [8]:

(2) The use of lasers/pulsed light devices for
non-ablative procedures cannot be dele-
gated to nonphysicians delegates, other
than an advanced health care practitioner
without the delegating physician being on
site and immediately available.

(3) The use of lasers/pulsed light devices for
ablative procedures may only be performed
by a physician.
In the latest 2012 publication, the Texas Board
has updated its position on the delegation of medi-
cal services from 2008. As of 2012, “a physician has
the authority to delegate a medical act to qualified
and properly trained persons if the physician deter-
mines that the act can be properly and safely per-
formed by that person and such delegation does not
violate any other statute. The delegating physician
remains responsible for delegated medical acts.”
A 2011 survey study of state medical boards
showed a wide variability in the regulation of
how responsibilities related to minimally inva-
sive cosmetic procedures are regulated [9].
Despite this variability, the consensus remains
that ultimate responsibility for performing any
medical procedure resides with the physician.
Conclusion
Guidelines and regulations for medical lasers
are essential for their safe and effective use.
As previously noted, there is no single, finite
standard of practice, therefore consultation
with the appropriate governing bodies and
professional organizations is necessary to
ensure the quality of care provided and the
safety of the laser patient, staff and
operator.
References
1. The laser revolution – laser skin surgery. Approved by
the Board of Directors, American Society for Laser
Medicine and Surgery, Inc., October 1, 2007.
B. D. Cressey et al.

47
2. The use of lasers, pulsed light, radio frequency,
and microwave devices. American Academy of
Dermatology, Approved by the Board of Directors,
February 22, 2002.
3. American National Standards Institute. American
National Standard for Safe use of lasers in health care
facilities: ANSI Z 136.3. Orlando, FL: Laser Institute
of America; 2011.
4. Lanzafame RJ.  Procedural skills for using lasers in
general surgery. American Society for Laser Medicine
and Surgery, Approved by the Board Directors,
August 2, 2012.
5. Procedural skill and technique proficiency for sur-
gery and other energy-based therapies in dermatol-
ogy. Approved by the Board of Directors, American
Society for Laser Medicine and Surgery, Inc., August
2, 2012.
6. Control of smoke from laser/electric surgical pro-
cedures. Hazards controls. HC 11. DHHS (NIOSH)
Publication 96–128, 1996.
7. Position statement on non-physician practice of
medicine and use of non-physician office person-
nel. Approved by the Board of Directors, American
Society for Dermatologic Surgery, May 2008.
8. Use of lasers/delegation of medical functions regu-
lation by state. Federation of State Medical Boards,
May 2012.
9. Choudhry S, et al. State medical board regulation of
minimally invasive cosmetic procedures. J Am Acad
Dermatol. 2012;66:86.
2  Laser Safety: Regulations, Standards and Practice Guidelines

49
© Springer International Publishing AG, part of Springer Nature 2018
K. Nouri (ed.), Lasers in Dermatology and Medicine,
Lasers for Treatment of Vascular
Lesions
Jayne Joo, Daniel Michael, and Suzanne Kilmer
Abstract
Lasers for the treatment of vascular lesions are
continually improving using the principles of
selective photothermolysis.
Important variables to consider in the treat-
ment of vascular lesions are size, depth, and
composition.
Effective treatment of vascular lesions
requires tailoring the light wavelength, flu-
ence, and pulse duration to the specifics of the
targeted lesion.
Keywords
Lasers · Vascular lesions · Selective
photothermolysis · Pulse duration · Epidermal
temperature control · Frequency-doubled
Nd:YAG (Potassium-Titanyl-Phosphate
[KTP]) · Pulsed dye lasers (PDL)
Alexandrite laser · Neodymium:Yttrium–
Aluminum–Garnet (Nd:YAG)
Dual wavelength combination lasers
Introduction
A large number of lasers and intense non-­
coherent pulsed light devices are available for the
treatment of vascular lesions. New devices have
been developed, and existing devices are continu-
ally being improved to increase their ability to
specifically target vessels while decreasing risk
of potential complication such as scarring. Here
we review lasers that are utilized for the treat-
ment of commonly encountered vascular lesions.
Principles of Laser Treatment
for Vascular Lasers
Selective Photothermolysis
In 1983, Richard Rox Anderson and John Parrish
proposed the theory of selective photothermoly-
sis, whereby laser energy can be used to create
targeted damage to cutaneous structures while
minimizing damage to surrounding tissue [1].
The selective destruction of vascular lesions with
light is based on the following tenets:
J. Joo
Department of Dermatology, University of California,
Davis, CA, USA
Sacramento VA Medical Center, Sacramento, CA, USA
e-mail: jsjoo@ucdavis.edu
D. Michael
Department of Mohs Surgery, Kaiser Permanente,
Walnut Creek, CA, USA
e-mail: daniel.x.michael@kp.org
S. Kilmer (*)
Department of Dermatology, University of California,
Davis, CA, USA
Laser and Skin Surgery Center of Northern
California, Sacramento, CA, USA
e-mail: skilmer@skinlasers.com
3

50
• The wavelength of light has to penetrate to at
least the depth of the target
• The energy is absorbed selectively by the target
• The heated target must cool quickly enough so
that it does not cause thermal damage to the
surrounding tissue.
The target (chromophore) for vascular lasers
is hemoglobin. Choosing the appropriate laser
involves selecting a wavelength with deep enough
penetration that is primarily absorbed by the vas-
cular target. There are commercially available
lasers ranging from 532 to 1064 nm for the treat-
ment of vascular lesions with non-coherent
pulsed light sources spanning an even broader
spectrum. Within this range, shorter wavelengths
scatter more quickly and penetrate less deeply
than longer wavelengths which can reach several
millimeters into the dermis before scattering ren-
ders it useless.
The wavelength of light that is preferentially
absorbed depends on whether it is bound to oxy-
gen. Oxygenated hemoglobin (oxyhemoglobin) is
normally the most abundant form of hemoglobin
and has three peaks of absorption (418, 542 and
577 nm) with decreasing absorption in the near-
infrared range [1]. Deoxygenated hemoglobin
(deoxyhemoglobin) has an absorption peak of
755 nm that is well targeted by the 755 nm wave-
length alexandrite laser. The absorption of light
energy by intravascular oxyhemoglobin results in
healing and destruction of vascular lesion.
The major chromophores competing for
absorption in the skin are melanin, water, and fat.
Melanin is primarily present in the epidermis and
may absorb incident laser light. This may reduce
the effective energy delivered to the vascular tar-
get and possibly cause direct thermal damage to
the epidermis. Melanin absorption spectrum
decreases with longer wavelengths from ultravio-
let (<400 nm) through the visible (400–760 nm)
spectrum (Fig.  3.1). Longer visible and near
infrared wavelengths are absorbed less by epider-
mal melanin and penetrate deeper into the dermis
than the shorter visible and ultraviolet wave-
lengths [2].
Pulse Duration
Based on the principle of selective photothermol-
ysis described by Anderson and Parrish, the size
of the chromophore determines optimal pulse
duration. The thermal relaxation time is defined as
the time it takes for a target structure to dissipate
50% of the absorbed energy into surrounding tis-
sue. This can be approximated by the square of
the diameter of the target structure. The ideal set-
ting would have high enough fluences with pulse
durations that are short enough to limit diffusion
of heat from target vessels while still causing pho-
tocoagulation [3]. Excessively long pulse dura-
tions that exceed the thermal relaxation time can
lead to diffusion of heat to surrounding tissue and
20,000
10,000
1000
100
10
1
0.1
200
HbO2
Water
Melanin
Hb
1000
Absorbance (cm-1)
5000
Wavelength (nm)
a
1,000,000
Tabulated molar extinction coefficient for hemoglobin in water
hbo2 cm-1/m
hb cm-1/m
100,000
10,000
1000
100
250
350
450
550
650
750
850
950
b
Wavelength nm
Fig. 3.1  Absorption curve for (a) hemoglobin, melanin, and water, and (b) oxygenated (red) and deoxygenated (blue)
hemoglobin
J. Joo et al.

51
thermal damage. In contrast, excessively short
durations can cause focal boiling of the blood
which may lead to cavitation-­induced vessel dis-
ruption which in turn can produce excessive pur-
pura without necessarily causing elimination of
the vessel.
Epidermal Temperature Control
Heat transfer to the epidermis during laser ther-
apy can cause untoward thermal damage. This
can occur by several mechanisms: direct
absorption of light energy, back scatter of light
from deeper tissue, and conduction of heat pro-
duced in the dermis. Selective cooling of the
epidermis is therefore very important before,
during, and after treatment and allows for
higher temperatures to occur in the target struc-
tures without damage to the epidermis. Current
methods for epidermal cooling include: direct
contact (conduction), forced cold air (convec-
tion), and cryogen spray (conduction and
evaporation).
Lasers for Treatment of Vascular
Lesions
Frequency-Doubled Nd:YAG
(Potassium-Titanyl-Phosphate [KTP])
Frequency-doubled
neodymium:yttrium-­
aluminum-­garnet
(Nd:YAG)
lasers
use
potassium-­titanyl-phosphate (KTP) crystals to
double the frequency, which halves the wave-
length from 1064 to 532  nm. Oxyhemoglobin
absorbs the light of this wavelength about as well
as it absorbs the light of 585  nm wavelength
(Fig. 3.1). This shorter wavelength is effective for
destruction of more superficial vessels whereas
longer wavelengths penetrate deeper and are bet-
ter suited for vessels that are located deeper in the
skin. Melanin also absorbs this wavelength well.
Therefore, efficient epidermal cooling is neces-
sary when using these devices, especially in
darker skin types that have higher epidermal mel-
anin content.
Pulsed Dye Lasers (PDL)
The flash lamp-pumped pulsed dye laser (PDL)
was the first laser developed for selective photo-
thermolysis of vascular lesions [1, 4]. It was ini-
tially designed to produce 577  nm light to
correspond with one of the oxyhemoglobin peaks
[5] (Fig. 3.1). The wavelength was increased to
585  nm to increase the depth of penetration,
improving efficacy for the treatment of deeper
vessels. The original pulsed dye lasers had short
pulse widths of 0.45 ms, whereas the next gener-
ation of PDLs could deliver high frequency
pulses that could be combined into longer com-
bined pulse widths of 1.5 ms. The longer pulse
widths allow treatment of larger vessels with less
extravasation of blood and therefore less purpura.
Although longer wavelengths allow deeper pen-
etration, hemoglobin absorption begins to drop
off rapidly as the wavelength increases. The next
generation of PDLs is also able to produce light
with wavelengths of 585, 590, 595, or 600 nm.
The most recent versions of pulsed dye lasers
have only the 595 nm wavelength but have adjust-
able pulse widths ranging from 0.45 to 40 ms to
provide optimal treatment parameters for various
vessel sizes.
Alexandrite Laser
Bluish vascular lesions often extend deeper and
contain more deoxyhemoglobin. PDLs are not
very effective against these lesions because their
wavelengths often do not penetrate deeply
enough and are not absorbed by deoxyhemoglo-
bin as well as they are by oxyhemoglobin.
Initially, the long pulsed alexandrite laser was
used for hair removal, but was found to be effec-
tive against violaceous deeper vascular lesions.
The long pulsed alexandrite laser utilizes the
deoxyhemoglobin absorption peak at 755 nm to
target certain vascular lesions [6]. In addition to
being well absorbed by deoxyhemoglobin, the
longer wavelength of the long pulsed alexandrite
lasers produced over longer pulse widths allows
the light energy to penetrate deeper into the der-
mis and to target larger vessels.
3  Lasers for Treatment of Vascular Lesions

52
Neodymium:Yttrium–Aluminum–
Garnet (Nd:YAG)
Neodymium:yttrium-aluminum-garnet (Nd:YAG)
lasers produce light at 1064 nm which penetrates
deeper than shorter wavelengths. However, at
this wavelength, oxyhemoglobin no longer
absorbs the energy better than the surrounding
dermis. These lasers can be effective, but the risk
of scarring is significant at fluences high enough
to effect vascular damage, so these lasers are less
often used [7]. Fluences and pulse width used at
this wavelength are dependent on vessel size,
location, and the oxygenation of hemoglobin.
Vessels with larger diameters require longer
pulse widths (Fig. 3.2). Conversely, small ves-
sels need shorter pulse widths but require higher
fluences as there is less chromophore (i.e., hemo-
globin) present.
Dual Wavelength Combination Lasers
Methemoglobin is hemoglobin in which the fer-
rous iron of the heme group has oxidized to ferric
iron. Unlike oxyhemoglobin and melanin, methe-
moglobin has higher absorption with increasing
wavelength from 700 to 1000 nm [8] and can be
targeted by Nd:YAG laser light. It has been
shown that pulsed dye lasers are able to induce
the transformation of oxyhemoglobin to methe-
moglobin resulting in a more selective target for
an Nd:YAG laser [9]. In addition, the thrombus
that can be formed by PDL energy also is a better
target for the 1064 nm light [9, 10]. Because of
the increased absorption of 1064 nm by methe-
moglobin and thrombus, lower fluences of the
Nd:YAG can produce vessel specific damage
while decreasing risk of thermal damage to sur-
rounding tissue.
PDL light only penetrates approximately
0.75 mm into the skin. For lesions with deeper
components, it is necessary to allow the PDL
formed products time to flow deeper into the
lesion before illumination with the deeper pene-
trating Nd:YAG laser. The combination PDL/
Nd:YAG therapy works best for superficial dis-
crete telangiectasias with vessels in the 0.2–
1.2 mm diameter range. Although PDL remains
the treatment of choice for vascular birthmarks,
the dual wavelength combination KTP/Nd:YAG
and PDL/Nd:YAG lasers may be helpful for
lesions that resistant to PDL alone [11, 12].
Intense Pulsed Light (IPL)
Intense Pulsed Light (IPL) devices produce high-­
energy, non-coherent light. Their output covers a
broad range of the light spectrum, often ranging
from near 500 nm to around 1200 nm with pulse
widths of several milliseconds. Cut-off filters are
used to limit the spectrum of the incident light to
the desired wavelengths. For treatment of vascular
a
b
Fig. 3.2  Blue facial veins (a) before and (b) after treatment with long-pulsed Nd:YAG 1064 nm laser [Excel V (5 mm,
110 J/cm2, 40 ms, 5 °C cooling with sapphire tip)]
J. Joo et al.

53
lesions, wavelengths shorter than 580–590 nm are
generally filtered out [13]. Newer devices filter out
the longer infrared wavelengths, reducing many of
the adverse effects of earlier devices [13]. These
devices usually have larger application tips which
cover larger surface areas and are well suited to
broader treatment areas.
Output varies by wavelength and by device, so
parameters tend to be device-specific. IPL devices
can be effective against capillary malformations,
telangiectasias, and small cherry angiomas [14].
Adverse effects include postinflammatory hyper-
or hypopigmentation, blistering, and scarring.
Vascular Lesions and Laser
Treatment Options
Capillary Malformations (e.g., Port
Wine Stains or Nevus Flammeus)
Capillary malformations are the most common
type of vascular malformation. Port wine stains
(PWS), also called nevus flammeus, are congen-
ital developmental malformations of the superfi-
cial dermal capillaries. They are present at birth,
grow as the child grows, and do not involute.
Treatment of PWSs was initially performed
with the continuous wave 488–514  nm argon
laser [15, 16]. One of the main problems with
the argon laser was that the pulse width could
not be controlled. This often led to scarring
from excess heat deposition. A laser with a lon-
ger wavelength and a controllable pulse width
was needed. To overcome the inadequacies of
the argon laser for treating these lesions, Richard
Rox Anderson and John Parrish developed the
theory of selective photothermolysis. This led to
the PDL becoming the treatment of choice for
these lesions. PDL selectively targets hemoglo-
bin and the pulse width more closely matches to
the thermal relaxation time of the target vessels
in PWSs [17].
Most PWSs start as pink macules with tiny
vessels, but with time these lesions become
larger, thicker, and tortuous [18]. In addition,
more of the hemoglobin in larger, older lesions
tend to be deoxygenated and are not targeted as
well by PDLs. For these reasons, PWSs are gen-
erally best treated with PDLs earlier in the pink
macular stage, as often seen in infants. More
mature hypertrophic bluish PWSs often require
longer pulse widths and even longer wavelengths
[19]. Successful treatment generally requires
repeated treatments, especially for larger lesions
and those on the distal extremities. As discussed
above, longer wavelengths can treat deeper ves-
sels in the lesion and may show improved rates of
clearance, although the decreased absorption by
hemoglobin necessitates higher fluences which
may be more likely to produce post-inflammatory
pigment changes.
Most patients see significant improvement but
complete clearance of the lesion is often not pos-
sible. Lesions in newborns tend to respond faster
and more completely than those in older patients.
There is much less melanin in neonatal skin com-
peting as a chromophore for the absorption of the
laser, and the lesions tend to be smaller and thinner
than in adults. All of these features render earlier
lesions more responsive to PDL than later lesions.
Pink macular PWSs are best treated using
585–595  nm wavelengths with a short pulse
width in the 0.45–1.5 ms range (Fig. 3.3). The
best spot size and energy used is dependent on
the specific PDL used, but for 10 mm spot size,
7.5 J/cm2 is often effective and for 12 mm spot
size, 7 J/cm2 is often needed, which may be the
maximum output available. For more resistant
PWSs, when higher energies are needed, we
found that the 7 mm spot size may be needed to
deliver 8–10 J/cm2. As higher energy levels are
used, the risk of purpura or ulceration increases
and these settings should be used with caution.
For PWS composed of larger vessels, the pulse
width may need to be lengthened. With longer
pulse widths, it becomes very important not to
exceed the ability of the cooling to protect the
epidermis. As with all lasers, appropriate cooling
is important to protect the epidermis while deliv-
ering sufficient heat to effectively destroy the
target.
Frequency-doubled Nd:YAG (Nd:YAG/KTP)
lasers produce sequential nanosecond length
pulses at a high frequency (>20,000 Hz) to pro-
duce semi-continuous pulses in the 2–20  ms
3  Lasers for Treatment of Vascular Lesions

54
range. The 532 nm wavelength does not penetrate
deeply but has been shown to be effective against
the superficial components of PWSs [20–22].
For hypertrophic PWSs, the PDL can be used
at 595 nm with similar settings as above; how-
ever, increasing the pulse width may improve
outcome. In addition, hypertrophic bluish PWSs
have more tortuous dilated vessels and slower
blood flow resulting in more deoxygenated
hemoglobin. Therefore, they may be better tar-
geted by the 755 nm wavelength of alexandrite
lasers, which utilizes the absorption peak of
deoxyhemoglobin near 755  nm (Fig.  3.4). We
often find settings of 35–40 J/cm2 with 12 mm
spot size and 3  ms pulse width with 50  ms of
spray cooling safe and effective. Care must be
taken to not overlap these pulses.
Nd:YAG lasers have also been shown to be
effective
against
capillary
malformations.
However, because this laser has a greater risk of
scarring, we rarely use this laser in infants or young
children. In a more mature PWS, 60–70 J/cm2 with
a 10–12 mm spot size and 3 ms pulse width have
improved resolution in those recalcitrant to
previous treatments.
More recently, the 595  nm wavelengths has
been used in combination with the 1064  nm
wavelength to take advantage of the improved
absorption of 1064 nm by methylated hemoglo-
bin so that less energy at 1064 nm is needed mak-
ing it safer. PDL and Nd:YAG lasers, when used
in combination, are generally set lower than
either would be if used alone. Fluences generally
used ­range between 6 and 10 J/cm2 for the PDL
and between 40 and 80  J/cm2 for the
Nd:YAG.  However, appropriate sample starting
settings for PDL is 7–8 J/cm2 and 10 ms, and for
Nd:YAG is 40 J/cm2 and 15 ms.
Multiple factors influence the effectiveness of
treatment, including thickness, patient age, and
location of the lesion. Treatment response
decreases with age and thickness of the lesion
[23]. The earlier these lesions are treated, the bet-
ter the results [24–26]. Not only do they clear
a
b
Fig. 3.3  Young boy with pink macular PWS (a) before and (b) after ten PDL treatments
J. Joo et al.

55
better, but the treatments are better tolerated. It is
often possible to achieve effective treatment
before 6 months of age. Treatment intervals are
typically 4–6 weeks apart though there is little
documentation establishing the optimal interval.
In fact, for resistant PWSs, 2 week intervals have
resulted in dramatic improvement without
increasing complication rates [27]. This may be
because more frequent treatments may prevent
neovascularization that would otherwise occur
before the next treatment. In addition, lesions
involving V2 distribution of the trigeminal nerve
as well as those in the V1 distribution over the
nose respond less well than those superior or
inferior to these regions [28, 29].
The most common adverse effect of PDL
treatment is purpura, though this is becoming less
common with newer lasers. It used to be thought
that production of purpura is necessary for suc-
cessful treatment. and therefore the lowest energy
settings that produce purpura were used. More
recently, we and others have found that these
lesions can be successfully treated without induc-
ing purpura [26].
Hemangiomas
In contrast to vascular malformations, infantile
hemangiomas (IH) are true neoplasms composed
of endothelial cells. They usually develop soon
after birth, but almost a third are present at birth
[30]. They are more common in Caucasians
(~10% of births) and are more likely in infants
that are premature, of very low birth weight
(<1.5  kg), born to mothers who had chorionic
­villus sampling, or those with a first-degree rela-
tive who have a vascular anomaly [31].
Although IHs can undergo a proliferative
phase during which they grow rapidly in size,
many involute as suggested by the mnemonic
often taught medical students, “50% resolve by
5 years, 70% resolve by 7 years, 90% resolve by
9 years.” However, end-stage or involuted hem-
angiomas often have residual superficial telangi-
ectasias with saggy, atrophic skin.
When IHs as located in cosmetically sensitive
areas or impinge on normal form and function, it
necessitates early intervention before permanent
damage results. For example, periocular lesions
a
b
Fig. 3.4  Middle aged Hispanic women with mixed (mac-
ular and hypertrophic) PWS (a) before and (b) after three
treatments with PDL (7.5 J/cm2, 1.5 ms, 10 mm spot size)
and alexandrite 755 nm laser (40 J/cm2, 3 ms, 12 mm spot
size)
3  Lasers for Treatment of Vascular Lesions

56
may obstruct vision and can impair visual cortex
development leading to permanent blindness.
Perioral lesions may frequently hemorrhage and
impair feeding ability, possibly leading to failure-­
to-­thrive. Perineal lesions often ulcerate and can
be very painful. Until recently, problematic IHs
were treated with systemic corticosteroids with
variable response [32, 33]. In 2008, Léauté-­
Labréze et al. made the serendipitous discovery
that propranolol given to infants with IHs for
treatment of cardiac problems also resulted in
dramatic regression of their IHs [34]. Propranolol
is now widely regarded as first line treatment for
problematic IHs [35]. Recently, topical timolol
has shown promise for the treatment of superfi-
cial IHs [36]. Timolol is hydrophilic and does not
permeate skin easily. Fractional CO2 laser-
assisted transdermal delivery of topical timolol
has shown promising results for deep IHs [37].
Both PDL and Nd:YAG lasers have been suc-
cessfully used to treat IHs [38, 39]. Hemangiomas
frequently have a stronger response to laser treat-
ment and need to be handled more carefully to
avoid iatrogenic ulceration. Though deep compo-
nents of the hemangioma will not be treated by
the 595 nm lasers (which have a limited depth of
penetration up to 1.2 mm), selective elimination
of the more superficial component of the heman-
gioma will preserve superficial skin architecture.
Because the Nd:YAG lasers can penetrate up to
6 mm, it has been proposed that sequential dual
wavelength modality of treatment is ideal for
mixed hemangiomas that have a superficial and
deep component [40]. In comparison to treatment
of PWSs, we typically start more conservatively
using settings approximately 1 J/cm2 lower and
then evaluate the response. In addition, these
lesions require more frequent monitoring with
shorter treatment intervals and careful adjust-
ments made to treatment settings based on evalu-
ation of the response from the previous visits.
Systemic and topical treatment options may be
combined with laser therapy to improve results. In
fact, when the IH has deep dermal ­vessels, lasers
may provide better results than topical timolol
alone because of a better depth of penetration [40].
Laser treatment can accelerate re-­epithelialization,
prevent hemorrhage, and restore skin integrity
and comfort (Fig. 3.5). Once the deep component
regresses, a more normal appearing epidermis is
more likely to remain (Fig. 3.6).
Spider Angiomas
Spider angiomas consist of a central arteriole
directly supplying a radiating network of dilated
superficial capillaries. Spider angiomas are com-
mon among people with lighter skin and are often
localized to areas of sun exposure, such as the
face, neck, and upper chest. They are also associ-
a
b
c
Fig. 3.5  Ulcerated congenital hemangioma (a) at presen-
tation, (b) after PDL treatment, and (c) resolved lesion
J. Joo et al.

57
ated with portal hypertension and hereditary
hemorrhagic telangiectasia (HHT) [18]. PDLs are
the laser of choice for the treatment of spider
angiomas. Treatment is aimed at the destruction
of the central “feeder” vessel which can then be
followed by destruction of the peripheral capillar-
ies. Diascopy can be used to target the feeder ves-
sel by blanching the draining capillaries. Fluences
of 7–10  J/cm2 using a 5–10  mm spot size are
often effective after just one or two treatments.
Telangiectasias
Facial telangiectasias are one of the most com-
mon complaints encountered by the cosmetic
dermatologist. They are more common in peo-
ple with lighter skin types and are associated
with a history of sun exposure and rosacea.
They represent dilated capillaries and post-cap-
illary venules with thickened walls. They are
superficial (200–250 μm deep) and have small
cross-sections (200–500 μm in diameter) [41].
PDL continues to be the most effective treat-
ment option. This laser used to be associated with
high rates of purpura [41]. However current ­opinion
is that telangiectasias can be treated with longer
pulse widths in the 6–10 ms range utilizing pulse
stacking where two to four pulses are “stacked”
immediately one on top of the other until vessel
clearing is noted without inducing purpura [42, 43]
(Fig. 3.7). In fact, even longer pulse widths in the
20–40 ms range may be effective. Treatment using
fluences between 7 and 10 J/cm2 and spot sizes of
5–10  mm are often effective with pulse widths
ranging from 6 to 10 ms (Fig. 3.8). For the com-
bined Cynosure Cynergy device, the PDL at
7–8 J/cm2 with a pulse width of 10–20 ms and with
a short or medium delay followed by Nd:YAG at
30–40 ms with pulse width of 15 ms is often effec-
tive (Fig. 3.9). Immediate coagulation/graying that
quickly clears is the desired endpoint. Purpura may
be more likely to develop in patients taking anti-­
coagulants (e.g., ASA, Coumadin, vitamin E, etc.).
IPLs have also been shown to be effective
against telangiectasias. They induce mild
a
b
Fig. 3.6  Scrotal hemangioma (a) at presentation and (b) after six treatments with PDL
3  Lasers for Treatment of Vascular Lesions

58
a
b
Fig. 3.7  Fifty-two year old woman with rosacea (a) before and (b) after two PDL treatments (7.5 J/cm2, 6 ms, and
10 mm spot size)
a
b
c
d
Fig. 3.8  Facial and nasal telangiectasias (a, b) before and (c, d) after two treatments with PDL (7.5 J/cm2, 6 ms, and
10 mm spot size)
a
b
Fig. 3.9  Sixty-one year old woman with facial telangiec-
tasias (a) before and (b) after treatment with PDL
(3 × 10 mm spot size, 17 J/cm2, 40 ms over linear, discrete
telangiectasias, followed by a second pass with 10 mm
spot size, 7.5 J/cm2, 6 ms)
J. Joo et al.

59
erythema and have a lower risk of inducing pur-
pura. Effective fluences range from 32 to 40 J/cm2
with pulse widths of around 20 ms [41]. While
PDLs continue to be the treatment of choice for
focal telangiectasias, IPLs may be more tolerable
for
some
patients
with
larger
­matted
telangiectasias and the diffuse erythema associ-
ated with rosacea.
Venous Lakes
Venous lakes are vascular ectasias that usually
develop after the age of 50 and may enlarge over
time [18]. Their size and depth can vary greatly.
As with most vascular lesions, laser therapy is
often effective and needs to be tailored to the
depth of the target. PDL is usually effective for
superficial venous lakes but longer wavelength
lasers, such as the diode (800–900 nm), alexan-
drite (755 nm), or Nd:YAG (1064 nm), are neces-
sary for thicker or deeper lesions. Fluences of
80 J/cm2, pulse durations of 60 ms or longer, and
10–12 mm spot sizes are often required; however,
such settings may put the epidermis at risk of
being thermally damaged. Therefore, appropriate
cooling is very important. In addition, there can
be significant heat return to the epidermis with
the longer pulse widths which makes post-laser
cooling an important consideration.
The aim with a PDL is to produce mild pur-
pura and edema. With diode and Nd:YAG lasers,
the goal is reduction in lesion thickness and
clearance of the ectatic vessel. For the larger and
deeper lesions, Nd:YAG with a spot size of 3 mm,
pulse widths of 30–100 ms, and fluences of up to
150 J/cm2 may be needed [41] (Fig. 3.10).
Other Vascular Anomalies
In addition to the above mentioned vascular
lesions, there are a variety of other less common
vascular anomalies for which surgery used to be
the mainstay of treatment. These lesions can
now be treated successfully with laser therapy.
For example, the lesions of blue rubber bleb
nevus syndrome, which are typically cutaneous
venous malformations of varying sizes that
enlarge with age, respond well to long pulse
alexandrite laser with a fluence of 40 J/cm2, spot
size of 12 mm, and efficient cooling (Fig. 3.11).
The long pulse Nd:YAG laser can also be uti-
lized with settings starting at 80 J/cm2 at 60 ms.
Again, appropriate cooling is extremely impor-
tant to minimize epidermal injury and scarring.
a
b
Fig. 3.10  Venous lake (a) before and (b) after single pulse with Nd:YAG 1064 nm laser (110 J/cm2, 30 ms, 5 mm spot
size)
3  Lasers for Treatment of Vascular Lesions

60
Lymphangioma can also be targeted by vascular
lasers if the concentration of hemoglobin is high
enough to provide a sufficient target for these
vascular lasers [44]. More violaceous lesions are
best treated with either long pulsed alexandrite
or Nd:YAG.
Conclusion
The introduction of lasers in cutaneous medi-
cine and the development of the theory of
selective thermolysis have provided clinicians
with effective therapies for the treatment of
vascular lesions. Understanding the tissue-
light interaction and the risks associated with
these therapies has allowed for improved end
results. The diverse range of devices available
require a more in-­depth understanding of
these lasers and broad band light devices to
provide patients with the most effective and
appropriate options.
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28. Orten SS, Waner M, Flock S, Roberson PK,
Kincannon J.  Port-wine stains. An assessment of 5
years of treatment. Arch Otolaryngol Head Neck
Surg. 1996;122(11):1174–9.
29. Renfro L, Geronemus RG.  Anatomical differ-
ences of port-wine stains in response to treat-
ment with the pulsed dye laser. Arch Dermatol.
1993;129(2):182–8.
30. Fishman SJ, Mulliken JB. Hemangiomas and vascular
malformations of infancy and childhood. Pediatr Clin
North Am. 1993;40(6):1177–200.
31. Hemangioma Investigator G, Haggstrom AN, Drolet
BA, et  al. Prospective study of infantile hemangio-
mas: demographic, prenatal, and perinatal character-
istics. J Pediatr. 2007;150(3):291–4.
32. Pope E, Krafchik BR, Macarthur C, et al. Oral versus
high-dose pulse corticosteroids for problematic infan-
tile hemangiomas: a randomized, controlled trial.
Pediatrics. 2007;119(6):e1239–47.
33. Bennett ML, Fleischer AB Jr, Chamlin SL, Frieden
IJ. Oral corticosteroid use is effective for cutaneous
hemangiomas: an evidence-based evaluation. Arch
Dermatol. 2001;137(9):1208–13.
34. Leaute-Labreze C, Dumas de la Roque E, Hubiche
T, Boralevi F, Thambo JB, Taieb A.  Propranolol
for severe hemangiomas of infancy. N Engl J Med.
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35. Hermans DJ, Bauland CG, Zweegers J, van Beynum
IM, van der Vleuten CJ. Propranolol in a case series
of 174 patients with complicated infantile haeman-
gioma: indications, safety and future directions. Br J
Dermatol. 2013;168(4):837–43.
36. Chakkittakandiyil A, Phillips R, Frieden IJ, et  al.
Timolol maleate 0.5% or 0.1% gel-forming ­solution for
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3  Lasers for Treatment of Vascular Lesions

63
© Springer International Publishing AG, part of Springer Nature 2018
K. Nouri (ed.), Lasers in Dermatology and Medicine,
Laser for Scars
Voraphol Vejjabhinanta, Shalu S. Patel,
and Keyvan Nouri
Abstract
Introduction of scar pathogenesis, epidemiol-
ogy, and classifications.
Indications and contraindications for laser
scar treatment.
Appropriate management of scars, includ-
ing pre- and post-operative techniques.
Keywords
Scar pathogenesis · Scar epidemiology · Scar
classification · Scar treatment · Atrophic scars
Outline
V. Vejjabhinanta, MD (*)
Dermatologic Surgery and Lasers Unit, Department
of Medical Services Ministry of Public Health,
Institute of Dermatology, Bangkok, Thailand
S. S. Patel, MD
The Permanente Medical Group, Redwood City,
CA, USA
e-mail: spatel@med.miami.edu
K. Nouri
Department of Dermatology and Cutaneous Surgery,
University of Miami Miller School of Medicine,
Miami, FL, USA
e-mail: knouri@med.miami.edu
4
• Introduction of scar pathogenesis,
epidemiology, and classifications
• Indications and contraindications for
laser scar treatment
• Appropriate management of scars,
including pre- and post-operative
techniques
• Potential adverse side effects of laser
scar treatment
• The use of laser therapy for atrophic
scars, including ablative, nonablative
and fractional resurfacing
• Future directions of laser scar therapy

64
Introduction
The skin is a primary barrier for protection and is
often submitted to damage from surgical proce-
dures, burns, trauma or inflammation. The skin
has an incredible capacity to renew and repair
itself through a process called wound healing, in
which a cascade of mechanisms result in
scarring.
The normal wound healing process, which
results in a flat and flexible scar, can be divided
into four stages: coagulation, inflammation,
proliferation, and remodeling. Once the injury
occurs, the inflammation phase begins after
activating the clotting and complement cas-
cade. Chemotactic factors such as prostaglan-
dins, complement factors, and interleukins (i.e.
IL-1) stimulate the migration of inflammatory
cells such as neutrophils and monocytes/macro-
phages. These cells help wound debridement.
Macrophages also release specific growth fac-
tors such as transforming growth factor Beta
(TGF-β) and platelet-derived growth factors
(PDGF), which initiate the formation of the
provisional wound matrix. The proliferation
phase involves the migration of fibroblasts,
increased endothelial cells and keratinocytes to
the site of injury. Fibroblasts are especially
important in forming the extracellular matrix,
which is made of collagens I and III, fibronec-
tin, elastin, and proteoglycans. The keratino-
cytes start the re-epithelialization process with
reconstruction of the disrupted basement mem-
brane. Revascularization occurs with endothe-
lial cells and angiogenic factors such as
fibroblast growth factor (FGF). As maturation
ensues, the collagen network and proteoglycans
are also remodeled. While both collagen types I
and III increase during the beginning of the
wound healing process, the contribution of col-
lagen type III decreases as remodeling takes
place.
An abnormal response to the wound healing
process results in hypertrophic scars (Fig. 4.1)
and keloids (Fig.  4.2). These are essentially
excess scar tissues that form at the site of
injury. Fibroblasts from keloids abnormally
respond by producing high levels of collagen,
particularly type I. In contrast, fibroblasts from
hypertrophic scars respond normally, with a
slight increase in collagen. The collagen fibers
in hypertrophic scars are more organized,
while those in keloids are arranged in whorled,
Fig. 4.1  A pink, smooth, shiny, well-circumscribed linear
hypertrophic scar at the lower abdomen after trans-abdominal
hysterectomy
• The skin’s normal wound healing
process involves coagulation, inflam-
mation,
proliferation
and
remodeling.
• Hypertrophic scars and keloids occur
when the skin’s normal wound heal-
ing process goes awry. Further, they
more commonly occur in ethnic skin.
• There are multiple techniques used to
treat these scars, and recent advances
in laser therapy have made lasers a
practical alternative.
V. Vejjabhinanta et al.

65
hyalinized bundles. Further, while angiogene-
sis diminishes during normal remodeling, but
persists during the development of keloids and
hypertrophic scars.
These can occur in all races, although they are
more frequently found in ethnic skin, ranging
from a 3 to 18 times higher incidence when com-
pared with Caucasians. The incidence has been
reported to be between 4.5% and 16% within
African-Americans, Chinese, and Hispanics.
Patients in their second to third decade of life are
more commonly affected, with the same preva-
lence in both sexes [1–3].
Hypertrophic scars are red, raised, and firm,
and usually appear within 1 month at the injury
site, especially sites under pressure or frequent
movement. Keloids, which can often be disfigur-
ing, are purple/red nodules that are often found
beyond the original injury site. Unlike hypertro-
phic scars, these appear within weeks or even years
from the initial injury. Keloids frequently are found
on the earlobes, anterior chest, shoulders and upper
back. Common processes that may lead to keloid
formation are ear piercings, tattoos, infections,
vaccination, burns, and inflammatory acne.
The treatment of hypertrophic scars and
keloids is challenging due to high recurrence
rates and adverse side effects. Previous methods
for treatment have included surgery, cryotherapy,
electrocautery and desiccation, dermabrasion,
intralesional corticosteroids, 5-fluorouracil, and
radiation. In terms of lasers, Ablative CO2 and
Erbium: YAG lasers were used for hypertrophic
scars but then discontinued. The pulsed dye laser
(PDL) is currently the laser of choice for hyper-
trophic scars, which have yielded more success-
ful results compared to keloids. It works via the
principle of selective photothermolysis, in which
the laser targets blood vessels, with the 585 nm
wavelength specifically absorbed by hemoglobin.
It is suggested that the microvascular destruction
causes subsequent ischemia and reduction of
scarring.
To appropriately treat hypertrophic scars and
keloids, a thorough understanding of the pro-
cesses by which they form is essential.
Fig. 4.2  Multiple keloids at the right
arm, shoulder and chest wall of an
African American woman
4  Laser for Scars

66
Indications and Contraindications
Patients typically seek medical help due to cos-
metic issues or associated symptoms. Thus,
indications for treatment of hypertrophic scars
include
functional
impairment,
cosmetic
appearance, and pruritis and dysesthesias. The
typical outcome of laser treatment is reduction
of the redness and height of the scar, improve-
ment of pliability, and symptomatic relief of
pruritis.
Factors that need to be taken into consider-
ation before treatment include patient skin type
and lesion type. Fair skinned individuals
(Fitzpatrick skin types I to III) tend to have a bet-
ter response and fewer side effects to treatment.
Patients with Fitzpatrick skin types IV to VI have
an increased risk of laser light absorption by epi-
dermal melanin, therefore less effective targeting
of the skin and increased risk of postoperative
hypo- or hyperpigmentation. It is suggested that
in these patients, a test spot is done to predict any
potential side effects. Lesion type also plays a
role in the success of laser treatment. Lesions that
have formed in less than a year and those that are
red and raised have proved to be ideal for laser
therapy.
Lasers have been found to be useful as a pre-
ventative measure as well. The 585 nm PDL was
found to be effective in preventing the formation
of hypertrophic scars in burn wounds. Further,
treating surgical scars starting on the day of
suture removal has yielded optimal results
(Figs. 4.3a, b).
Techniques
a
b
Fig. 4.3  (a) A linear surgical scar on the anterior mid
upper chest. The right section received 585 nm PDL with
pulse duration of 450 μs, the middle remained as a con-
trol, and the left section received 585 nm PDL with pulse
duration of 1.5 ms. (b) One month after the third PDL
treatment. There was a significant clinical difference
between treated and untreated sites
• Pre-operative management includes
obtaining a detailed history and exam
of the patient’s scars, and if any prior
therapy has been done. The area of
treatment should be cleaned thoroughly
and topical anesthetic may be used for
comfort. It is important to take a pic-
ture of the scar before therapy to track
• Indications for treatment include side
effects, functional impairment, and
aesthetics.
• It is important to take into account
the patient’s skin type and lesion type
prior to therapy.
V. Vejjabhinanta et al.

67
Pre-operative Management
It is important to get a good patient history before
laser treatment. The history of the scar or keloid
in terms of age, evolution, and previous treat-
ments is helpful in determining treatment prog-
nosis. It is ideal to treat hypertrophic scars early,
possibly within the first few months of appear-
ance. This is because of the numerous blood ves-
sels present at this time. Previous treatments,
such as cryotherapy, may cause increased fibro-
sis, and thus adjustments of laser parameters and
treatment sessions may need to be made. Location
of the scar is also important to note. Dierickx
et al. have found that facial scars respond better
to treatment [4]. Nouri et al. agree and have found
that facial, shoulder, and arm scars respond better
than those on the anterior chest wall [5]. However,
Alster and Nanni found no relation between scar
location and response to treatment [6].
The PDL treatment for hypertrophic scars and
keloids is an outpatient procedure. It typically
does not require anesthesia unless requested by
the patient. If so, a topical anesthetic cream may
be applied 30–60  min before the procedure.
Make-up any other creams must be removed from
the treatment area with soap and water. In assess-
ing the lesion, the physician should note its size,
color, height, pliability, and associated symptoms.
Vancouver Scar Scale or Miami Scar Scale, for
example, may be used to ensure consistency. A
picture should be taken prior to treatment for
comparative purposes. It should be taken with the
same camera, lighting, and distance. The patient
and physician should be wearing eye protection at
all times during the procedure.
Description of the Technique
The physician must first calibrate the laser and
set parameters to be used. The ideal setting is
585 nm PDL at 450 μs pulse duration, using a
spot size of 7–10 mm, with the fluence ranging
from 3.5 to 7.5 J/cm2. When using a smaller spot
size, the fluence should be increased; however
initial treatments should all begin with a lower
fluence. In ethnic skin, we prefer using a lower
fluence (3–3.5 J/cm2 with a 10 mm spot size) in
order to reduce any complications from this
procedure.
Once set, the physician should place the hand-
piece over one end of the scar and start applying
the laser pulses over the entire scar surface in a
continuous pattern until reaching the opposite
end. A 10% overlap is generally accepted.
Laser treatment may be used alone or in com-
bination therapy with intralesional corticoste-
roids or 5-FU. Alster compared PDL treatment
alone with laser therapy combined with intrale-
sional corticosteroid treatment and found that
both were similarly effective with no significant
difference [7]. It is important to remember, how-
ever, that if using intralesional corticosteroids,
the injections should be done following the laser
procedure. If done before, blanching of the lesion
occurs and there is substantial risk of losing the
laser target. An average of 10–40 mg/mL imme-
diately after laser treatment can be used.
Post-operative Management
Post-operative management includes strict sun
avoidance to avoid pigmentation alterations. The
treated area should be cleansed as normal with
soap and water. Trauma to the site should be
avoided. Subsequent treatments may be done
within 4–6 weeks.
its progress and note any side effects
that may occur.
• Laser therapy involves appropriately
calibrating and setting the laser
parameters. It may be used alone or
in conjunction with intralesional
medical therapy. Multiple treatments
are needed to obtain better results.
• Post-operatively, the patient should
avoid the sun and keep the treatment
area clean and protected.
4  Laser for Scars

68
Side Effects/Complications and Their
Management and Prevention
A typical complaint from laser treatment is pain
similar to that of a rubber band snapping against
one’s skin. A burning or itching sensation in the
treated area is common as well, but subsides
within a couple days if not sooner. Purpura is the
most commonly expected side effect, appearing
immediately after the procedure and lasting
7–10  days. Pigmentation alteration may also
occur. If hyperpigmentation occurs, a bleaching
cream may be used. Also, subsequent treatments
may need to be deferred to ensure effective laser
targeting of the scar.
Rare complications include crusting, oozing,
and vesiculation of the lesion. In these cases, the
area should be kept moist with ointment and may
be covered with nonocclusive dressing to avoid
contact. Subsequent treatments must be post-
poned until complete healing of the site. Also, the
physician must reconsider the settings used to
prevent further complications.
Laser for Atrophic Scar
Atrophic scarring (such as those from acne,
chicken pox, or even striae) is depression of the
skin due to the destruction of normal dermal or
subcutaneous tissue architecture by inflamma-
tion, infection, or trauma.
There are many treatment modalities for this
condition including topical vitamin A acid appli-
cation, focal or regional chemical peeling, sub-
cission, punch grafting, injection of fillers,
dermabrasion, and laser resurfacing.
Nowadays, laser resurfacing for acne scar can
be classified into three main categories:
1. Ablative resurfacing
2. Non-ablative resurfacing
3. Fractional resurfacing
Ablative Laser Resurfacing
The most common devices used for this tech-
nique are the carbon dioxide laser and Erbium
YAG laser. Both of them are considered the gold
standard treatment for acne scars and offer prom-
ising results after treatment. However, this
method can be quite complicated and can have
multiple drawbacks including:
• The need for antibiotic prophylaxis for
bacterial-­viral-fungal superimposed infections.
• The need for adequate anesthesia and sedation
(some are systemic administration in combi-
nation with local anesthesia injection).
• The need for complicated post-operative care
such as analgesia and dressing, along with
post-operative antibiotic coverage.
• The risk for post-operative bleeding when
using Erbium YAG laser because it has a high
water absorption and thus cannot penetrate
deeply (compared with the CO2 laser), pre-
venting enough heat production to ligate blood
vessels.
• A high tendency for post-operative erythema
or pigmentary alteration, which may prolong
downtime, especially for individuals with
skin of color who experience post-inflamma-
tory hyperpigmentation and/or permanent
hypopigmentation.
• Atrophic scars resulting from acne,
chicken pox, trauma, or even striae
can be treated with laser therapy. The
three main categories of therapy
include ablative resurfacing, nonab-
lative resurfacing, and fractional
resurfacing.
• Ablative resurfacing offers effective
therapy, but side effects and adverse
events post-operatively limit its use.
• Nonablative resurfacing is considered
safe, but may not be as effective as
ablative resurfacing.
• Fractional resurfacing offers the
effectiveness of ablative resurfacing
and the safety of nonablative resurfac-
ing. Studies have achieved improved
results with this method, though a
small percentage of patients experi-
enced side effects.
V. Vejjabhinanta et al.

69
In an effort to reduce these drawbacks, some
modalities that have been introduced are pre-­
operative bleaching agents, combination topi-
cal anesthesia with regional nerve block, and
oral analgesic and sedation. Further, the follow-
ing devices were introduced to decrease
complications:
• The high energy-short pulsed CO2 laser, which
offers low tissue damage when compared with
the conventional continuous mode CO2 laser.
• The variable pulsed or dual-mode Erbium
YAG laser, because the long pulse duration
allows it to penetrate deeper than the short
pulse duration alone, resulting in an optimal
reaction for stimulating skin regeneration
and ligation of blood vessels to diminish
bleeding [8, 9].
• The combined-mode Erbium YAG/CO2 laser
system, which offers the dual benefit of hav-
ing the ablative effect of the Erbium YAG
laser and the coagulation effect of the CO2
laser [10].
Nonablative Laser Resurfacing
This is another modality that was quite popular at
the turn of the century due to low complication
rates and very low to almost no downtime when
compared with ablative resurfacing, chemical
peeling or dermabrasion. Some laser devices that
demonstrated improvement of acne scars include:
• The 1064 nm Q-switched Nd: YAG Laser [11]
• The 1064 nm Long pulse Nd: YAG Laser [12,
13]
• The 1320 Nd: YAG Laser [14, 15]
• The 1450 nm diode Laser [16]
• The 1540-nm erbium-doped phosphate glass
Laser [17]
• The 585  nm flashlamp-pumped pulsed dye
laser and Intense pulse light system also show
benefit for post acne erythema [18, 19]
These lasers are alternatives for people who
may desire a less aggressive form of treatment;
however, patients must be informed of the cost
of treatment, that they may require multiple ses-
sions, and to hold realistic expectations of their
outcome.
Fractional Devices
Both physicians and patients have tolerated the
high complication rate of ablative laser resurfac-
ing and low efficacy of non-ablative laser resur-
facing, but fractional resurfacing is a recently
introduced alternative that may be the best of
both devices. It particularly excels in offering
promising
results
for
facial
rejuvenation,
melasma, and acne scars. This system uses the
concept of fractional photothermolysis by creat-
ing numerous microscopic thermal injury zones
of controlled width, depth and density that are
surrounded by normal skin which serves as a res-
ervoir for rapid tissue healing [20].
The benefits of this system are less downtime
and side effects than the conventional ablative
laser has, and an increased efficacy of tissue
regeneration than the nonablative method offers.
There are many devices launched in the market
now, the most popular being the Erbium-doped,
Erbium YAG, CO2, radiofrequency, Xenon lights.
There are many studies that have demon-
strated the efficacy of the 1550 laser system for
acne scar treatment. Alster et al. used the 1550 nm
erbium-doped fiber, with fluences of 8–16 J/cm2
at a density of 125–250 MTZ/cm2 in 8–10 passes
on 53 patients (Fitzpatrick skin types I–IV) with
atrophic acne scars. They found that nearly 90%
of patients achieved clinical improvement aver-
aging 51–75%; however, multiple treatments
were necessary [21]. Lee et al. treated 27 Asian
patients (Fitzpatrick skin types IV-V) with mod-
erate to severe facial acne scars. Each patient
received three to five sessions of 3–4 weeks apart.
At 3  months after the final treatment, eight
patients (30%) assessed themselves as having
excellent improvement, 16 patients (59%)
assessed themselves as having significant
improvement, and the final three patients (11%)
assessed themselves as having moderate improve-
ment. Adverse events were limited to transient
pain, erythema and edema [22]. Emmy at el
4  Laser for Scars

70
reviewed 961 patients who were treated with
1550 nm erbium doped laser. They found that 73
(7.6%) patients developed complications. The
most frequent complications were acneiform
eruptions (1.87%) and herpes simplex virus out-
breaks (1.77%). Other rare complications include
erosions, postinflammatory hyperpigmentation,
prolonged erythema, prolonged edema, dermati-
tis, impetigo, and purpura [23].
Other fractional laser systems such as the frac-
tional CO2 laser and fractional Erbium YAG laser
are, by theory, more ablative than the 1550
erbium-doped laser. However, the optimal treat-
ment parameters for achieving a successful acne
scar treatment with minimal side effects need to
be studied. Interestingly, Vejjabhinanta et al. per-
formed a study of acne scar treatment by using a
fractional radiofrequency microneedle system.
They found that this system was safe and effec-
tive with minimal side effects in Asians [24].
Future Directions
Prevention of surgical scar formation is impor-
tant. An effective way to do this is to use PDL
routinely after suture removal. For new, red,
hypertrophic scars, combination therapy with
intralesional corticosteroids and 5-FU may be
effective. However, for older scars that are not
red, PDL treatment may not be warranted. These
lesions may be treated with intralesional steroids
and/or 5-FU. Triamcinolone (TAC) is one of the
most commonly used steroids for intralesional
injection of keloids and hypertrophic scars. It can
be administered (10–40 mg/mL) every 4–6 weeks
until resolution. 5-FU (45–50  mg/mL) may be
injected a few times per week to once per month
depending on the quality of the lesion.
Corticosteroids work by inhibiting migration of
inflammatory cells, vasoconstriction, and inhibi-
tion of fibroblast and keratinocyte proliferation.
The mechanism of 5-FU is primarily inhibition
of fibroblast proliferation. Both of these methods,
though effective, can cause pain at the injection
site and side effects such as pruritis and purpura.
Studies combining these with PDL treatment are
promising.
Further studies, possibly combining various
lasers such as short-pulse and long-pulse, may
offer interesting results and a potential frontier
for scar treatment.
Conclusion
The mechanisms of hypertrophic scar and
keloid formation are interesting and important
in identifying optimal treatments. Various
treatment options are available, and lasers pro-
vide a novel and efficacious approach to ther-
apy. While the 585–595 nm PDL seems to be
the optimal laser, recent results of the frac-
tional
laser
resurfacings
promising.
Abnormalities in wound healing remain a
challenging topic. Patients suffer physical and
emotional consequences. Addressing and
managing these factors with minimal side
effects in all patients should be the goal of
future studies.
References
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3. Oluwasanmi JO.  Keloids in the African. Clin Plast
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• These methods, however, do not come
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their
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MC. Comparison of a 1,064 nm laser and a 1,320 nm
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Dermatol Surg. 2005;31(8 Pt 1):903–9.
14. Rogachefsky AS, Hussain M, Goldberg DJ. Atrophic
and a mixed pattern of acne scars improved
with a 1320-nm Nd:YAG laser. Dermatol Surg.
2003;29(9):904–8.
15. Sadick NS, Schecter AK.  A preliminary study
of utilization of the 1320-nm Nd:YAG laser for
the treatment of acne scarring. Dermatol Surg.
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19. Cartier H. Use of intense pulsed light in the treatment
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4  Laser for Scars

73
© Springer International Publishing AG, part of Springer Nature 2018
K. Nouri (ed.), Lasers in Dermatology and Medicine,
Laser Treatment of Leg Veins
Julie K. Karen and Shields Callahan
Abstract
Damaged venous valves result in varicose or
spider vein formation. Commonly, venous
obstruction is caused by increased pressure of
reverse blood flow within the superficial
venous valve or from direct traumatic injury to
the vein.
Keywords
Leg veins · Spider veins · Sclerotherapy
Venous insufficiency · Endovenous ablation
Laser
Introduction/Background
Visible leg veins are a common concern among
dermatology patients. It is estimated that half of
the adult population is affected with venous dis-
ease and approximately 20% of women have vis-
ible varicosities [1]. The prevalence of varicose
veins is higher in women than men and it increases
with age in both sexes. Elderly women carry the
greatest burden of disease, with 54% of women
over the age of 65 affected by visible leg veins [2].
In addition to advanced age and female gender,
family history, standing occupation, history of
deep vein thrombosis (DVT), pregnancy and hor-
monal therapy are additional risk factors for
venous disease [3]. Surgical stripping of the veins
remained the standard of treatment for varicosi-
ties for over 100 years but these procedures were
associated with high rates of serious complica-
tions, long post-operative recovery periods and an
unacceptably high risk of varicose recurrence [4].
Newer therapies and minimally invasive proce-
dures, including lasers and sclerotherapy, circum-
vent many of the pitfalls associated with the
previous vein treatments and have replaced tradi-
tional surgical techniques as the gold standard in
the treatment of leg veins. There are numerous
laser and light therapies that are currently avail-
able to treat leg veins and they play a crucial role
in specific patient populations.
Basic Anatomy
The lower extremity venous system is comprised
of interconnected veins that function in a coordi-
nated effort to return blood flow to the heart. Leg
veins are classified as superficial, deep or perforat-
ing. The superficial venous system is a largely
redundant network of thin walled vessels located in
the dermis and subcutaneous tissue. The superficial
J. K. Karen (*)
Department of Dermatology, CompleteSkinMD,
NYU Langone Medical Center, New York, NY, USA
e-mail: drkaren@completeskinmd.com
S. Callahan
Department of Dermatology, Virginia Commonwealth
University School of Medicine, Richmond, VA, USA
e-mail: shields.w.callahan@vcuhealth.org
5

74
veins feed into the deep veins at various points by
way of the perforating veins. The deep veins are
located within the muscular fascia where they
travel alongside major arteries before ultimately
merging with the femoral vein.
Chief among the superficial leg veins are the
great saphenous vein (GSV), the small saphenous
vein (SSV) and the lateral venous system. The
GSV, formerly known as the greater saphenous
vein, drains the majority of blood from the lower
leg. It originates at the medial aspect of the foot,
courses anteriorly to the medial malleolus and
travels up the medial aspect of the calf and thigh
before merging with the femoral vein at the
saphenofemoral junction, which is located in the
inguinal region.
The SSV is responsible for returning blood
collected from the posterior aspect of the lower
leg. The SSV originates in the lateral aspect of
the foot. It traverses the posterior calf between
the heads of the gastrocnemius muscle and typi-
cally merges with the popliteal vein at the level of
the knee. In some individuals, an intersaphenous
connection known as the Giacomini vein allows
for direct communication between the SSV to the
GSV. Instead of draining into the popliteal vein,
the SSV merges with the Giacomini vein and
travels medially before draining into the GSV.
The lateral venous system or Albanese system
is an embryologic venous remnant commonly
found in a subset of the population. Reflux may
occur in these aberrant veins even in patients with
no other clinically significant evidence of venous
disease.
Venous Structure and Function
The venous system differs from the arterial sys-
tem in several ways. Firstly, veins are under rela-
tively lower pressure and therefore require
neighboring muscle contractions to “pump” the
blood uphill against gravity. To that end, veins
also feature one-way valves to prevent backflow.
Lastly, vein walls are less elastic and less muscu-
lar than their arterial counterparts, which accounts
for their increased recoil and distension. In com-
bination, these features comprise a “muscle-vein
pump” that facilitate the return of blood flow to
the heart.
Effective return of lower extremity blood to the
heart relies on a properly functioning venous sys-
tem characterized by functioning valves and an
unobstructed path. The absence of one or both of
these components impedes the blood flow upward
and out of the legs and results in a congested,
high-pressure system and dilated, leg veins.
In response to prolonged periods of high pres-
sure, the veins become dilated, thicker and tortu-
ous. The appearance of these abnormal vessels is
distressing to many patients prompting them to
seek cosmetic treatment. Later stages of chronic
venous disease include progressively larger
veins, dyspigmentation, edema, lipodermatoscle-
rosis and ulceration which correspond to more
severe venous disease [5].
Dilated vessels are further classified based on
their size. Telangiectasias are collections of
dilated venules that appear as red to purple,
thread-like vessels that measure <1 mm in diam-
eter. Reticular veins are slightly larger, bluish
vessels which measure between 1 and 3  mm.
Telangiectasias and reticular veins are collec-
tively referred to as “spider veins.” Varicose veins
are larger (>3 mm), bluish tortuous vessels that
commonly represent tributaries of the saphenous
veins (GSV and SSV).
Evaluation
All patients who present for leg vein treatment
require a thorough history and exam, including a
comprehensive, circumferential evaluation of the
legs with photographic documentation. Imaging
is recommended for patients with venous bulging
at the zones of influence of the saphenous sys-
tem, a history of prior venous surgery or inter-
vention, a strong family history of venous disease,
poor prior response to venous treatments, or
symptoms of chronic venous disease, which
include: heaviness, swelling, pain, pruritus, burn-
ing, cramping, or restless leg syndrome (RLS).
Duplex imaging is the modality of choice for
assessing the pattern and extent of venous disease
and informing interventional approaches [6].
J. K. Karen and S. Callahan

75
Contraindications
The majority of varicosities arise in the setting
of valvular insufficiency and chronic reflux.
However, treatment of leg veins in patients with
venous outflow obstruction (including a DVT) is
contraindicated, as the varicosities represent cru-
cial bypass routes that allow blood to circumvent
the obstruction.
Current Therapy Strategies
The current treatment approaches available for
leg veins include:
1) Surgical open technique
2) Minimally invasive procedures (Sclerotherapy,
Laser and Light Sources)
3) Endovascular Ablation (Endovenous Laser
Ablation and Radiofrequency Ablation)
Irrespective of the treatment approach
selected, compression plays an important,
adjunctive role. Compression therapy in the form
of graduated, medical-grade compression stock-
ings has been shown to improve the efficacy of
vein treatments and decrease post-procedural
complications [7]. Although the ideal duration of
compression remains disputed, we recommend
strict compliance for at least 2–4  weeks post-­
procedurally [7–9].
Laser Technology
Although sclerotherapy remains the gold stan-
dard for the treatment of leg veins, lasers and
light sources are increasingly utilized in the man-
agement of cosmetic and medically significant
venous disease. Patients may seek laser therapy
in an effort to avoid the discomfort associated
with sclerotherapy injections, due to an inability
to comply with compression, or due to a poor
prior experience with sclerotherapy. In some
instances, patients mistakenly assume that laser
treatment will be less painful than sclerotherapy
injections [10].
Laser therapy represents an appropriate ther-
apy or adjunctive therapy for the treatment of leg
veins in the following clinical settings:
1) Needle-phobic patients
2) Poor prior response to sclerotherapy or scle-
rosant allergy
3) Treatment of matted telangiectasia induced
by prior sclerotherapy
4) Tiny vessels that may not be amenable to
sclerotherapy
There are several challenges associated with
treating leg veins with laser therapy. Leg veins
are less responsive than facial vessels to laser
therapy owing to their heterogeneous size and
diameter, deeper depth in the dermis, elevated
hydrostatic pressure and higher content of deoxy-
genated blood. However, over the past several
years, several advances in the field have allowed
for safer treatment and more reliable outcomes.
Improved epidermal cooling modalities, deeper
penetrating wavelengths and variable, millisec-
ond pulse widths have contributed to more pre-
dictable and better-tolerated outcomes.
Laser treatment is based on the principle of
selective photothermolysis. Selective photother-
molysis is the process of destroying a targeted,
microscopic biological structure (chromophore)
through the delivery of a specific wavelength of
light. The aim of selective photothermolysis is to
deliver adequate energy to destroy the selected
chromophore without causing damage to the sur-
rounding tissue [11]. Three fundamental con-
cepts
form
the
foundation
of
selective
photothermolysis:
1) Wavelength should be preferentially absorbed
by the target
2) Pulse duration must not exceed the thermal
relaxation time (TRT) of the target in order to
minimize the transference of heat to surround-
ing structures
3) Fluence must be high enough to produce ade-
quate thermal damage to the intended target
As the target chromophore in vascular lesions
is oxyhemoglobin, the three major absorption
5  Laser Treatment of Leg Veins

76
peaks in the visible spectrum are 418, 542 and
577 nm. In addition, there is a broad, less selec-
tive absorption peak in the near-infrared (750–
1100) region. Accordingly, there is excellent
absorption by the visible light lasers and intense
pulsed light. However, these shorter wavelengths
do not penetrate sufficiently and so may only heat
the anterior vessel wall leading to incomplete
thrombosis. Though less selective, longer wave-
length devices penetrate deeper and achieve more
efficient vessel closure by heating the entire ves-
sel circumference. However, due to lesser speci-
ficity, higher fluences are needed when employing
near-infrared lasers translating into a greater risk
of collateral damage. The following lasers may
be employed for the treatment of leg veins:
1) Potassium Titanyl Phosphate (KTP): 532 nm
2) Pulsed Dye Lasers (PDL): 585–595 nm
3) Intense
Pulsed
Light
Devices
(IPL):
500–1200 nm
4) Alexandrite: 755 nm
5) Diodes: 800–983 nm
6) Neodymium:
yttrium
aluminum
garnet
(Nd:YAG): 1064 nm
Pulse duration, defined as the span of time that
the laser interacts with the target, should be
selected based on the size of the target vessel. In
general, longer pulse durations are required to
effectively treat leg veins relative to those used
for the treatment of port wine stains or smaller
caliber facial telangiectases. Leg veins are non-­
uniform targets with both a strongly absorbing
portion (blood) and weakly absorbing portion
(endothelial cells within vessel wall). Altshuler’s
extended theory of selective photothermolysis
dictates that a pulse duration that exceeds one-­
half of the calculated TRT is necessary to achieve
effective vessel closure. Mathematical models
have demonstrated that intravascular tempera-
tures are fairly similar within a wide range of
pulse durations [12]. However, clinical observa-
tions have shown that 20–60 ms pulses outper-
form 3  ms pulses for the treatment of a broad
range of vessels [12]. It is theorized that these
longer pulse durations cause more collagen
shrinkage within the vein walls, which in turns
leads to more complete vessel collapse [12].
Furthermore, longer pulse durations (≥20  ms)
are less likely to cause vessel rupture and associ-
ated purpura and post-inflammatory hyperpig-
mentation [13]. In practice, pulse durations of
10–100 ms are employed.
Vessel heating results in the conversion of
hemoglobin to met-hemoglobin (met-Hb), which
demonstrates altered absorption properties.
Specifically, met-Hb has an absorbance 4.75
times that of Hb-O2 and 20 times that of Hb.
Absorption therefore improves with subsequent
pulses delivered sequentially due to this early
conversion to met-Hb, allowing for sub-threshold
fluences to be used. Similarly, longer pulse dura-
tions may be effective at lower fluences due to
this early conversion.
Selection of spot size, like pulse duration, is
based on the size of the target vessel. Although
scattering is not directly affected by spot size, the
probability that a scattered photon will remain
within the collimated beam, thereby contributing
to the overall energy, is proportional to spot size
[14]. In short, there is a greater chance that a scat-
tered photon will stay “in the fold” if the spot size
is larger. Therefore, a larger spot size loses less
energy through scattered photons and can effec-
tively deliver more overall energy to the intended
target than a smaller spot size of the same wave-
length [14]. Caution must be exercised when using
larger spot sizes in order to avoid causing thermal
damage to surrounding tissue. Smaller spot sizes
are adequate and safe for more deeply penetrating,
longer wavelength lasers. In practice, a spot size
that approximates (or is slightly larger than) the
target vessel diameter is thought to achieve opti-
mal results and minimal side effects [15].
Fluence is selected to ensure that the tempera-
ture inside the vessel target reach at least 70 °C;
the temperature at which point the blood coagu-
lates and the vessel closes [16]. Thermal damage
to surrounding tissue may be lessened with the
use of epidermal cooling modalities, which
reduce epidermal temperature while allowing
peak temperatures to be achieved within target
vessels. The most commonly used devices
include contact cooling, convection air-cooling,
cryogen spray cooling, and cold gels.
J. K. Karen and S. Callahan

77
Specific Lasers for Leg Vein
Treatment
Potassium Titanyl Phosphate Laser
(KTP)
The KTP laser, with its 532-nm wavelength, cor-
responds to the second absorption peak of hemo-
globin (542  nm) and is an obvious choice for
vascular lesions. However, this hemoglobin
absorption peak overlaps with melanin absorption
and accounts for the high rates of associated dys-
pigmentation. One study of 56 patients with telan-
giectasia who underwent three treatments with a
KTP demonstrated only modest results; 27% of
treated patients with telangiectasia ≤0.6 mm did
not have any benefit [17]. And none of the patients
with telangectias measuring between 0.7 and
1.0  mm improved at all [17], consistent with a
maximum penetration depth of 0.75 mm for this
wavelength Furthermore, 23% of all patients
developed hyperpigmentation [17]. For these rea-
sons, KTP should be reserved for the treatment of
isolated, small caliber vessels (<0.7  cm) in
patients at low risk for dyspigmentation. Superior
results have been achieved with larger spot sizes
(3–5 mm), longer pulse durations (10–50 ms) and
higher fluences (14–20 J/cm2).
Long Pulsed Dye Laser (PDL)
The first generation PDL (585-nm) showed lim-
ited success in the treatment of telangiectasias
because it could not deliver adequate fluence
with its relatively short pulse duration. The sec-
ond generation PDL, with its longer 595-nm
wavelength, and modified pulse width, was
designed to allow for deeper penetration and
higher energy delivery. The 595-nm PDL has
been shown to effectively treat small, linear tel-
angiectasia at fluences of 10–20 J/cm2 and pulse
durations ranging from 1.5 to 40  ms [18].
However, commonly observed side effects
include purpura, edema and hyperpigmentation
[19]. Hyperpigmentation, which may persist for
weeks, has been observed at rates as high as 58%
of treated sites [18]. Therefore, the long pulsed
PDL must be used cautiously in patients with
darker skin types and those at risk for
­hyperpigmentation. Like the KTP, the long
pulsed PDL is an acceptable choice for the treat-
ment of small caliber vessels (<1 mm) in lighter
skin patients who are at low risk for hyperpig-
mentation. There may be a role for combining
sclerotherapy with PDL (or another laser) in a
single treatment session to enhance treatment
efficiency, although optimal treatment parame-
ters have yet to be defined (Fig. 5.1).
a
b
c
Fig. 5.1  (a) Patient 1 immediate before leg vein treat-
ment (b) Patient 1 immediately after treatment with
foamed sclerotherapy of the reticular veins and PDL of
the telangiectasia (c) Patient 1 1 week after treatment
5  Laser Treatment of Leg Veins

78
Intense Pulsed Light (IPL)
IPL devices deliver high intensity, non-coherent
light over a range of wavelengths ranging from
500 to 1200  nm, thereby distinguishing them
from lasers. Filters may be applied to narrow the
emitted spectrum and to allow for more specific
targeting of select chromophores. The theoretical
benefit of these devices is their ability to target
both oxygenated and deoxygenated Hb within
vessels at multiple depths. A 550- or 570-nm fil-
ter is typically used, delivering primarily yellow
and red light with a minimal component of near-­
infrared light. Relatively longer filters may be
used in patients with darker skin types to lessen
pigmentary adverse effects.
In 1996, Goldman et al. demonstrated encour-
aging results with an IPL device in the treatment
of leg telangiectasias [20]. In a large, multicenter
trial, 79% of the 159 subjects with leg telangiec-
tasia ranging in size from 0.4 to 1 mm achieved
clearances of 75–100% after a series of treat-
ments [20]. There were minimal adverse side
effects reported; the most common of which was
dyspigmentation, which was seen in only 7% of
treatments [20].
However, another study in 1998 comprising
120 subjects with either facial or leg telangiecta-
sia, did not yield the same promising results [21].
Although there was >80% clearance achieved
after one treatment with a filter wavelength of
either 570 or 590  nm, there were several study
limitations [21]. All of the 40 patients with leg tel-
angiectasia underwent either selective surgery or
sclerotherapy prior to the IPL treatment, thereby
confounding the results [21]. In addition, there
was a high rate of adverse side effects: approxi-
mately 50% of patients developed hyperpigmen-
tation, and two patients development blistering
[21]. The high rate of side effects observed in this
study are likely due to the small therapeutic win-
dow and the difficulty of handling the device. The
discrepancy between these two studies also speaks
to the high degree of inter-­operator variability.
In general, like the visible light lasers, IPL
should be reserved for use by experienced opera-
tors for the treatment of fair skinned individuals
with small (<1 mm), superficial vessels.
Long Pulsed 755 nm Alexandrite
Laser
With its 755-nm wavelength, the long pulsed
alexandrite (LPA) laser can reach larger diameter
vessels situated deeper in the dermis than either
the KTP or PDL lasers. However, the absorption
coefficient of hemoglobin is much less at this
longer wavelength. In 1999, a study of 28 patients
with leg veins treated with the LPA outlined the
optimal treatment parameters as a fluence of 20 J/
cm2 and pulse duration of 20  ms [22]. A 48%
clearance of vessels sized 0.4–1 mm cleared after
three sessions, but smaller caliber vessels
responded poorly [22].
More recently, higher fluences have been
shown to be safe when combined with skin cool-
ing modalities, as demonstrated by Kauvar and
Lou in 2000 [23]. In their study of 20 female sub-
jects with leg veins ranging in size from 0.3 to
2  mm, they demonstrated marked clearance of
telangiectasia and reticular veins following a sin-
gle treatment utilizing fluences of 60–80 J/cm2.
Side effects included high rates of purpura and
pigmentation [23].
Despite relatively low absorption by hemoglo-
bin, the LPA may have some utility for the treat-
ment of vessels sized 0.4–3 mm. The introduction
of skin cooling devices has allowed for higher
fluences to be safely employed. Side effects,
including high rates of purpura, telangiectatic
matting and pigmentation limit the utility of this
device [24].
Diode
The diode laser is characterized by near-infrared
wavelengths ranging from 800 to 983 nm, which
allow for deeper penetration into the dermis
where they can target slightly larger veins. This
wavelength corresponds to the tertiary hemoglo-
bin peak and explains its efficacy in targeting
vessels. And because this wavelength is poorly
absorbed by melanin, it is associated with less
risk of hyperpigmentation.
The 800-nm diode laser (DL) has been shown
to be effective in the treatment of leg vessels
J. K. Karen and S. Callahan

79
measuring 3–4 mm in diameter [20]. In a small
study of ten women with skin types II-IV, the DL
was used to treat leg veins at 2 month intervals
for a maximum of three treatments [20]. After
6 months, over half of the patients experienced
clearance [20]. Blue veins measuring 3–4  mm
located on the thigh responded best [20]. There
was an overall high degree of patient satisfaction,
minimal discomfort, and no long-term complica-
tions reported [20].
A combination of the diode laser with a radio-
frequency (RF) current may also have a place in
the treatment of leg veins. A study of 40 patients,
skin types II-IV, who underwent a combination
of diode 900-nm with RF for a maximum of three
treatments, at 2 week intervals, showed encour-
aging results; 82% of patients had over 50%
clearance at the 6  month assessment [21].
Treatments were well tolerated and there were no
significant side effects reported [21].
More recently, intravenous injections of
indocyanine-­green (ICG) have been shown to
enhance the efficacy of diode laser treatments for
leg telangiectasia [25]. ICG, a green pigment,
strongly absorbs near infrared radiation and con-
verts >90% of radiation into thermal heat energy
[25]. This dye can be injected into vessels imme-
diately prior to laser therapy (ICG + DL) where
the exogenous pigment acts as a transient, easily
targeted chromophore thereby enhancing vessel
coagulation. In a 2013 study, 29 subjects with
bilateral leg telangiectasia were treated with
Nd:YAG laser and ICG + DL in a side-by-side
comparison with one single treatment [25].
Clearance rates were significantly higher in the
ICG + DL treated legs relative to the Nd:YAG
[25]. Further studies are needed to outline its
clinical utility and define its safety parameters
but the initial results are promising.
Nd:YAG
The Nd:YAG laser emits a 1064 nm wavelength
of light. Compared to other lasers that target
hemoglobin, the Nd:YAG has the lowest absorp-
tion of melanin, which accounts for its improved
safety profile in patients with darker skin types.
The longer wavelength also allows for deeper
penetration in the dermis and it can effectively
treat larger leg veins, up to 3  mm in diameter.
However, hemoglobin has a lower absorption
coefficient at this wavelength, which necessitates
higher energies be used to achieve adequate ves-
sel heating. These higher energies account for the
increased pain associated with treatments. Skin
cooling modalities are of critical importance and
local anesthesia may be required. Furthermore,
vigilance to avoid overlap is essential and sequen-
tial pulses should be spaced more than 1  mm
apart to avoid bulk heating.
A 2006 study investigated the optimal pulse
durations of the Nd:YAG for treating leg telangi-
ectasias. The results of 18 women with leg telan-
giectasias ranging in size from 0.1 to 1.6  mm
treated with the Nd:YAG demonstrated that lon-
ger pulse durations outperformed shorter dura-
tions with respect to both vessel clearance and
adverse side effects [14]. Short pulse durations
(3–20 ms) were associated with higher rates of
post-inflammatory hyperpigmentation and pur-
pura as compared to longer pulse durations (40–
60 ms) [14]. The authors recommend selecting
the smallest fluence and smallest spot size to
achieve optimal vessel clearance with pulse dura-
tion of 20–60 ms. Their study also uncovered dif-
ferences in skin cooling modalities; patient pain
was noticeably improved with the refrigerated air
device (Zimmerman Elektromedizin, Irvine, CA)
as compared to the cryogen spray (DCD Candela
Corporation, Wayland MA) prompting a mid-­
study transition to using refrigerated air for all
the subsequent study participants [14]. When
cryogen cooling is employed, care should be
taken to avoid excessive cooling, which can lead
to cryogen burns.
In general, when treating smaller vessels,
shorter pulse durations, smaller spot sizes and
higher fluences of 250–400  J/cm2 are required,
whereas longer pulse durations, larger spot sizes
and more moderate fluences (100–200 J/cm2) are
employed when treating larger vessels (which
contain more target chromophore) [26]. As
always, laser safety precautions, including appro-
priate protective eyewear for the patient and cli-
nician are essential to avoid devastating ocular
5  Laser Treatment of Leg Veins

80
injury, which can occur with this deeply penetrat-
ing wavelength.
Of important note, the Nd:YAG is the only laser
to date that has been shown to demonstrate results
similar to sclerotherapy for the treatment of leg tel-
angiectasias up to 3 mm in diameter. Several stud-
ies have demonstrated nearly equivocal outcomes
with the Nd:YAG 1064 nm as compared to sclero-
therapy, although laser is typically perceived as
more painful [10, 27–29] (Figs. 5.2 and 5.3).
Post-operative End Points
The procedure end point of laser and light
source treatments on leg veins includes either
vessel disappearance (which corresponds to
complete contraction) or vessel darkening
(which corresponds with coagulation) with or
without surrounding tissue erythema. Urtication
and blurring of the vessel margins typically
occurs within 10  min of treatment. Blanching
may portend epidermal injury and should be
avoided. Sequential passes should be spaced at
least 1  mm apart when utilizing the 1064  nm
laser which carries a risk for bulk heating and
collateral damage. A multiple (up to 3) pass
approach is acceptable and sometimes neces-
sary with the other devices. Purpura should be
avoided as it portends a higher risk of post-
inflammatory hyperpigmentation. Strict sun
avoidance is essential both prior to and for
4  weeks following treatment to further mini-
mize pigmentary alteration.
a
b
Fig. 5.2  (a) Patient 2 before leg vein treatment (b)
Patient 1 after leg vein treatment with 1064 nm Nd:YAG
laser
a
b
Fig. 5.3  (a) Patient 3 before leg vein treatment (b)
Patient 3 after leg vein treatment with 1064 nm Nd:YAG
laser
J. K. Karen and S. Callahan

81
Side Effects/Complications
Side effects following laser treatment for visible
leg veins are typically mild and transient. The
most commonly reported adverse effects include
pain, purpura, and post-inflammatory hyperpig-
mentation (or less commonly hypopigmenta-
tion) (Fig. 5.4). The incidence of pigmentation
increases with the size of the treated vessel and
with darker skin types. In more severe cases,
thermal injury, ulceration, blistering, persistent
dyspigmentation and scarring may occur.
Furthermore, the risk that the patient may not
achieve an appreciable improvement in the
appearance of their leg veins should also be
addressed. Lastly, patients should be counseled
about the possible need for multiple treatment
sessions.
The most feared consequences associated
with the treatment of visible leg veins is not
unique to lasers; elimination of enlarged leg
veins in the setting of venous outflow obstruc-
tion removes the crucial bypasses of the venous
system. Obliterating these vessels with any
modality (laser, sclerotherapy, surgery etc.)
could prove catastrophic, and the significance of
a thorough pre-treatment evaluation cannot be
overstated.
Diligent sunscreen and compression hose, in
the form of medical-grade compression stock-
ings, may improve the efficacy of vein treatments
and minimize adverse side effects.
Conclusion
Although sclerotherapy remains the gold stan-
dard for the treatment of leg veins, laser ther-
apy represents an effective alternative or
adjunctive treatment for the elimination of
small vessels measuring <3  mm. Lasers
should be considered for those patients with
tremendous fear of needles, sclerosant allergy,
telangiectatic matting from prior sclerother-
apy and for vessels refractory to prior
sclerotherapy.
Current lasers employed for leg veins
include: Nd:YAG, PDL, diode, LPA, IPL and
KTP.  Selection of the appropriate laser is
based on the size and location of the vessels in
addition to the patient’s skin type. The single
most useful laser for leg telangiectasias is the
Nd:YAG 1064, which can yield results similar
to sclerotherapy and is safe for darker skin
types.
Often times, a combination of different
lasers may provide the most benefit owing to
the various size vessels that comprise most leg
disease. Common adverse effects include pur-
pura, post-­inflammatory dyspigmentation and
pain; the latter can be mitigated with skin
cooling devices employed intra-procedurally.
a
b
Fig. 5.4  (a) Widespread hyperpigmented patches
4  months following inappropriate use of PDL in dark
skinned individual with unwanted leg veins. (b) Mottled
hypopigmentation in an actinically damaged patient more
than 10 years following KTP treatment for telangiectasia
of the medial ankle
5  Laser Treatment of Leg Veins

82
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J. K. Karen and S. Callahan

83
© Springer International Publishing AG, part of Springer Nature 2018
K. Nouri (ed.), Lasers in Dermatology and Medicine,
Lasers and Lights for Treating
Pigmented Lesions
Emmy M. Graber and Jeffrey S. Dover
Abstract
• Pigmented lesions were initially treated
with destructive non-selective lasers.
• Now pigment selective Q-switched lasers
used.
• Pigmented skin lesions are exceedingly
common.
• Selective destruction of pigmented lesions
relies
on
the
theory
of
selective
photothermolysis.
• Melanin has a broad absorption spectrum
with absorption steadily decreasing with
increasing wavelength.
• Several Q-switched lasers fall within the
melanin absorption spectrum. Their nano-
second pulse duration is effective since it is
shorter than the thermal relaxation time of
melanin.
Keywords
Pigmented lesions · Tattoo removal · Q switched
lasers · Solar lentigo · Selective photothermoly-
sis · Picosecond lasers Melanin · Nevus of Ota ·
Melasma Hyperpigmentation
Outline
Introduction
History
• Pigmented lesions were initially treated
with destructive non-selective lasers.
• Now pigment selective Q-switched and
long pulsed green light lasers as well as
Intense Pulsed Light devices are used.
Epidemiology
• Pigmented skin lesions are exceedingly
common.
Basic Science
• Selective destruction of pigmented
lesions relies on the theory of selective
photothermolysis.
• Melanin has a broad absorption spec-
trum with absorption steadily decreas-
ing with increasing wavelength.
• Several Q-switched and millisecond
domain lasers fall within the melanin
absorption spectrum. The nanosecond
E. M. Graber (*)
Dermatology Institute of Boston, PC,
Boston, MA, USA
e-mail: egraber@dermboston.com
J. S. Dover
Dermatology, Yale University School of Medicine,
Chestnut Hill, MA, USA
Surgery, Dartmouth Medical School,
Hanover, NH, USA
Dermatology, Brown Medical School,
Providence, RI, USA
e-mail: jdover@skincarephysicians.net
6
Initially Modified from: Kaminer, M.S., Dover, J.S.,
and Arndt, K.A.  Atlas of Cosmetic Surgery. 2002.
W.B. Saunders Company.

84
or picosecond pulse durations are effec-
tive since they are shorter than the ther-
mal relaxation time of melanosomes.
Millisecond domain pulses which are
shorter than the thermal relaxation time
of melanocytes and pigmented epider-
mal cells.
• Intense pulsed light and non-selective
fractional non ablative lasers are also
effective
Indications and Contraindications
Epidermal Pigmented Lesions
• Lentigines, Café au lait macules, and
ephelides are common epidermal pig-
mented lesions that respond to laser
treatment.
• Shorter laser wavelengths may suffice as
deep tissue penetration is not necessary.
• Multiple treatments are often needed for
complete removal.
Dermal Pigmented Lesions
• Melanocytic nevi, nevus of Ota,
melasma, post-inflammatory hyperpig-
mentation, and drug induced pigmenta-
tion are dermal pigmented lesions that
can be treated with lasers.
• Longer wavelengths may be needed to
reach the pigment.
• Multiple treatments are necessary.
• Anesthesia is not usually needed.
Techniques
Pre-operative Management
• It is important to obtain a medical his-
tory prior to treatment and to educate
patients about the potential outcomes.
• Topical anesthesia may be needed for
some larger or dermal pigmented lesions.
• Appropriate protective eyewear should
be on all persons in the room.
Description of Technique
• Laser parameters depend on the particu-
lar laser, the patient’s skin phototype,
and the type of lesion.
• Adequate fluence should result in an
immediate uniform ash white color.
Post-operative Management
• An occlusive ointment should be applied
and patients should be educated on the
healing process.
Adverse Events
Side Effects/Complications
• Post-inflammatory hyperpigmentation,
an inadequate response and recurrence
of the lesion are the most common side
effects.
Prevention and Treatment of Side Effects/
Complications
• Using the appropriate laser and fluence
can reduce side effects.
• Educating patients so that there are
realistic expectations can also help to
reduce
patient
frustration
and
complications.
Future Directions
• Pico second (10−12) domain lasers that are
used for tattoo removal appear to be effec-
tive in other pigmented lesions.
Conclusions
Introduction
• Pigmented lesions were initially treated with
destructive non-selective lasers.
• Now pigment selective Q-switched nanosec-
ond and picosecond domain and millisecond
domain lasers used.
• Intense pulsed light and non-selective frac-
tional non ablative lasers are also effective
• Pigmented skin lesions are exceedingly
common.
• Selective destruction of pigmented lesions
relies
on
the
theory
of
selective
photothermolysis.
• Melanin has a broad absorption spectrum with
absorption steadily decreasing with increasing
wavelength.
• Several Q-switched lasers fall within the mel-
anin absorption spectrum. Their nanosecond
or picosecond pulse durations are effective
since they are shorter than the thermal relax-
ation time of melanocytes.
• Millisecond domain pulses which are shorter
than the thermal relaxation time of melano-
cytes and pigmented epidermal cells.
• Intense pulsed light and non-selective frac-
tional non ablative lasers are also effective.
E. M. Graber and J. S. Dover

85
Abstract
• Pigmented lesions were initially treated with
destructive non-selective lasers.
• Now pigment selective Q-switched lasers
used.
• Pigmented skin lesions are exceedingly
common.
• Selective destruction of pigmented lesions relies
on the theory of selective photothermolysis.
• Melanin has a broad absorption spectrum with
absorption steadily decreasing with increasing
wavelength.
• Several Q-switched lasers fall within the mel-
anin absorption spectrum. Their nanosecond
pulse duration is effective since it is shorter
than the thermal relaxation time of melanin.
Keywords
Pigmented lesions
Tattoo removal
Q switched lasers
Solar lentigo
Selective photothermolysis
Picosecond lasers
Melanin
Nevus of Ota
Melasma
Hyperpigmentation
History
The application of lasers for pigmented lesions
began in 1963 when Leon Goldman and col-
leagues found that 0.5  ms pulses of ruby laser
radiation was selectively absorbed by pigmented
skin [1]. These investigators also discovered that
the threshold radiant exposure for epidermal
damage was 10–100 times lower for a quality
switched (Q-switched) ruby laser (QSRL) with a
pulse duration of 50 ns [2]. Despite these early
findings, the ability of the QSRL to selectively
target pigment was not initially appreciated.
Instead, for many years, pigmented lesions were
treated with nonselective continuous wave
sources such as the argon [3] and carbon dioxide
lasers [4]. After using these more tissue destruc-
tive devices, the selective Q-switched lasers at
wavelengths other than 694  nm were found to
target melanin. In the late 1980s Anderson et al.
demonstrated that Q-switched Nd:YAG laser
pulses at 1064, 532, and 355  nm selectively
diminished melanin. This group also showed that
the longer wavelengths (which are less well-­
absorbed by melanin) required a higher energy
fluence to be effective. Over the last 20  years,
after further investigation, pulsed lasers and
intense pulsed light sources have become the
treatment of choice for epidermal, and pulsed
lasers the choice for dermal pigmented lesions
and tattoos.
Epidemiology
Pigmented skin lesions are exceedingly common
in all races. Some pigmented lesions are congeni-
tal while many are acquired. With increasing sun
exposure, pigmented lesions become more preva-
lent. In a quest to reverse photoaging, there are
countless patients that desire lightening or
removal of these lesions. For some patients, there
appears to also be a cultural influence to correct
dyspigmentation.
Basic Science
Laser-Tissue Interactions in Pigmented
Skin
The ability of laser and light sources to diminish
pigmented lesions is based on the principle of
selective photothermolysis. (3) Described in
1983 by Anderson and Parrish, selective photo-
thermolysis predicts that there can be selective
thermal damage to an absorbing target using
appropriate laser parameters and pulse character-
istics. This principle requires: 1) the use of a
wavelength that is well absorbed by the target, 2)
a pulse duration that is shorter than the thermal
relaxation time (the time required for a heated
target to cool by 50%), 3) a sufficiently high
energy density to achieve the desired tissue
6  Lasers and Lights for Treating Pigmented Lesions