Lasers have been used successfully to treat a variety of vascular lesions including superficial vascular malformations (port-wine stains), facial telangiectases, haemangiomas, pyogenic granulomas, Kaposi sarcoma and poikiloderma of Civatte. Lasers that have been used to treat these conditions include argon, APTD, KTP, krypton, copper vapour, copper bromide, pulsed dye lasers and Nd:YAG. Argon (CW) causes a high degree of non-specific thermal injury and scarring and is now largely replaced by yellow-light quasi-CW and pulsed laser therapies. The pulsed dye laser is considered the laser of choice for most vascular lesions because of its superior clinical efficacy and low-risk profile. It has a large spot size (5 to 10mm) allowing large lesions to be treated quickly. Side effects include postoperative bruising (purpura) that may last 1-2 weeks and transient pigmentary changes. Crusting, textural changes and scarring are rarely seen.

1. LASERS IN DERMATOLOGY
Karolinekersin E
Assistant professor

2. LASERS
 Lasers have become an important part of the
dermatologist’s arsenal for the treatment of skin
diseases.
 As such, familiarity with the usage and
indications of this treatment modality has
become important in the field of dermatology.
 In addition to their numerous aesthetic
indications, lasers have proven to be efficacious
in treating both primary skin diseases and
cutaneous malignancies.
2

3. Milestones in laser development
YEAR PHYSICIANS DISCOVERY
1960 Ali Javan, William
Bennett Jr. and Donald
Herriott
Helium-neon (HeNe) laser
1960 Peter P. Sorokin and
Mirek J. Stevenson
Uranium laser
1961 Leo F. Johnson and Kurt
Nassau
Neodymium-doped solid
state laser
1961 J. McClung and Robert W.
Hellwarth
Quality switching (Q-
switching) technique to
shorten the pulse length
to nanoseconds
3

4. 1964 William Bridges Argon Laser
1964 Joseph E. Geusic and
Richard G. Smith
Nd: YAG (neodymium-
doped YAG) laser
1964 Kumar Patel carbon dioxide laser
1967 Bernard Soffer and Bill
McFarland
Dye laser
1970 Basov, V.A. Danilychev
and Yu. M. Popov
Excimer laser
CONTD..
4

5. Contd..
1972 Charles H. Henry Quantum well laser
1976 John M.J. Madey Free-electron laser
(FEL).
1994 Jérôme Faist,
Federico Capasso,
Deborah L. Sivco,
Carlo Sirtori, Albert
L. Hutchinson and
Alfred Y. Cho
Semiconductor laser
that can
simultaneously emit
light at multiple
widely separated
wavelengths
5

6. Contd..
1996 Wolfgang Ketterle Pulsed atom laser
1997 Shuji Nakamura, Steven
P. DenBaars and James S.
Speck
Gallium-nitride (GaN)
laser
2009 Chunlei Guo Femtosecond pulsed
laser
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7. LASER TREATMENT
 Laser (L-A-S-E-R) stands for light
amplification by stimulated emission of
radiation.
 In simpler terms, a laser is a single-wavelength
(one color of light) source of high-energy light,
which can be accurately focused to transmit
that light onto a very small area.
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8. LASER INTERACTION ON SKIN
 When a laser is used on the skin, the light
may be absorbed, reflected, transmitted, or
scattered.
 The first law of photobiology, the
Grotthus-Draper law, states that light must
be absorbed by tissue for a clinical effect to
take place, whereas transmitted or reflected
light has no effect
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9. Contd..
 The energy absorbed is measured in joules per square
centimeter and is known as the energy density or
fluence.
 The amount of absorption is determined by the
chromophore present in the skin and whether a
wavelength that corresponds to the absorptive
characteristics of that chromophore is used.
 The principle endogenous chromophores of the skin
are water, melanin, and hemoglobin, whereas tattoo
ink is an example of an exogenous chromophore
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10. EFFECTS OF LASER
Photochemical
Once laser energy is absorbed in the skin, 3 basic effects
are possible:
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11. PHOTOTHERMAL EFFECTS
Photothermal effects
occur when a
chromophore absorbs
the corresponding
wavelength of energy
and destruction of the
target results from the
conversion of absorbed
energy into heat
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12. PHOTOCHEMICAL EFFECTS
Photochemical effects derive
from photosensitizer related
reactions that serve as the
basis of photodynamic therapy
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13. PHOTOMECHANICAL EFFECTS
Extremely rapid thermal expansion can
lead to acoustic waves and subsequent
photomechanical destruction of the
absorbing tissue
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14. Contd..
 Although all 3 types of laser effects can occur,
photothermal and photomechanical reactions are most
commonly observed in current cutaneous laser surgery
practice.
 The depth of penetration of laser energy into the skin
is dependent upon absorption and scattering.
 Although scattering is minimal in the epidermis, it is
greater in the dermis as a result of the presence of
collagen fibers, which are responsible for the
majority of tissue scatter in the skin
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15. Contd..
 The amount of scattering of laser energy is inversely
proportional to the wavelength of incident light.
 In general, the depth of penetration of laser energy
increases with wavelength until the midinfrared
region of the electromagnetic spectrum.
 Penetration of 300- to 400-nm wavelengths are
limited by strong scattering of the beam whereas
scattering is minimal at longer wavelengths (1000-
1200 nm), allowing greater penetration into the skin.
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16. Contd..
 However, wavelengths in the midto upper-infrared
range of the electromagnetic spectrum penetrate
superficially as a result of high absorption by tissue
water, the principle chromophore at this range.
 As such, selective vaporization of water-containing
tissue serves as the basis of ablative laser skin
resurfacing.
16

17. Anderson and Parrish’s theory
 The theory describes how controlled destruction of a
targeted lesion is possible without significant thermal
damage to surrounding normal tissue.
 To achieve selective photothermolysis, a proper
wavelength that is absorbed preferentially by the
intended tissue target or chromophore is selected.
 To limit the amount of thermal energy deposited within
the skin, the exposure duration of the tissue to light
(pulse duration) must be shorter than the chromophore’s
thermal relaxation time (defined as the time required
for the targeted site to cool to one half of its peak
temperature immediately after laser irradiation). 17

18. Contd..
 Finally, the energy density (fluence, measured in
joules per square centimeter) delivered by the laser
must be sufficient to achieve destruction of the
target within the allotted time.
 Therefore, on the basis of these principles, laser
parameters (wavelength, pulse duration, and fluence)
can be tailored for specific cutaneous applications to
effect maximal target destruction with minimal
collateral thermal damage.
18

19. TYPES OF LASERS AND THEIR
CUTANEOUS APPLICATION
Laser type Wavelength Cutaneous
application
Argon (CW) 418/514 nm Vascular lesions
Argon-pumped
tunable dye
(quasi-CW)
577/585 nm Vascular lesions
Copper
vapor/bromide
(quasi-CW)
510/578 nm Pigmented lesions,
vascular lesions
Potassium-
titanyl-phosphate
532 nm Pigmented lesions,
vascular lesions 19

20. LASER SURGERY FOR LESIONS AND
SKIN CONDITIONS
 There are many different types of lesions and skin
conditions that can be treated with laser surgery.
These include birthmarks, which are skin
abnormalities present at birth
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21. Port-wine stains
 A port-wine stain is a birthmark
caused by blood vessels.
 It creates a pink, red, or purple
discoloration of the skin.
 As the child grows, the mark may
become darker. Port-wine stains
can appear on any part of the
body and can vary in size.
 They can be linked to a
neurological disorder.
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22. Contd..
 Pulsed dye lasers are most commonly used. Adults may
have this procedure done with only local anesthesia
on an outpatient basis.
 This means they can go home the same day.
 Children or adults with large port-wine stains may
be treated under general anesthesia. Multiple
treatments may be needed.
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23. Hemangiomas
 Hemangiomas are a common type of
birthmark. They are caused by an
abnormal buildup of blood vessels.
Hemangiomas may vary in appearance.
 They may range from red raised
patches to deeper purple areas.
 Hemangiomas usually appear within
the first month of a child’s life and
grow quickly for the first year. They
may start to go away by the time the
child is 5 years old.
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24.  About half of all hemangiomas become
smaller on their own by age 5.
 Hemangiomas may be in the top skin layers. Or
they may be deeper in the skin.
 Surgery, injections into the hemangioma, or
an oral medicine called propranolol may be
used for large or growing hemangiomas.
 These treatments may also be used for
hemangiomas that are causing problems
because of their location. Multiple
treatments with a laser may be needed.
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25. Telangiectasias
 These are small blood vessels under
the surface of the skin.
 They may be red, purple, or blue.
 They are often seen on the face, upper
chest, and neck. Related vessels
called spider veins can be found in the
legs.
 Removal is usually done for cosmetic
reasons. There are many causes of
telangiectasias.
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26.  These include heredity, sun damage, hot and spicy
foods, emotions, hormones, some medicines, and
rosacea.
 Treatment of these lesions may include lasers or
sclerotherapy.
 Sclerotherapy is a procedure that uses a small needle
to inject medicine into the vessels.
 This makes them shrink. New vessels may continue to
develop throughout the person's life.
 It depends on what caused the lesion to form. KTP
lasers and pulsed dye lasers are commonly used on the
face.
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27. PSORIASIS AND VITILEGO
 Excimer 308-nm light is a form of targeted
phototherapy that delivers a specific wavelength (308
nm) of ultraviolet B (UVB) radiation using an excimer
laser or an excimer lamp. Both have shown similar
results regarding efficacy, but have technical
differences.
 Excimer light treatment is a development of whole
body narrowband UVB. Narrowband UVB delivers energy
at a wavelength between 311–312 nm for the treatment
of localised psoriasis and vitiligo
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28.  Excimer laser therapy is an option for the treatment
of localised vitiligo and moderately severe localised
psoriasis and unresponsive to topical treatments.
 It is often combined with topical therapies to enhance
response, for instance, topical calcineurin inhibitors
and topical steroids.
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29. PSORIASIS AND VITILEGO
29

30. TREATMENT
 There are no widely accepted disease-specific protocols for excimer light
treatment.
 Patients attend 1–3 times weekly. The amount of UV delivered is carefully
calculated and monitored taking into account the skin type, age, skin
condition, site and response to treatment.
 The duration of treatment is shorter than for whole body phototherapy. Some
response may be noted as early as 6–8 treatments and complete response may
take 20–30 sessions. The average length of treatment is about seven weeks.
 Some patients have long remission periods, while others may relapse within
3–6 months.
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31. ADVANTAGES
 Healthy skin surrounding the affected areas is not
exposed to radiation
 Different templates are used according to the area to be
treated
 A higher dose of radiation can be delivered, with a
reduced cumulative dose of irradiation
 In some cases, a shorter course of treatment is effective
 It can be used in areas difficult to reach with
conventional phototherapy, such as ears and genitals
 It can be used in children, as it is a relatively friendly–
looking piece of equipment.
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32. Precancerous Lesions:
 Almost all surgeons agree that cancerous lesions should
be removed via scalpel (with a knife during surgery) to
ensure clear borders and complete removal.
 In addition to making sure a skin cancer has "clear
margins," this assures that there is a sample for a
pathologist to look at to determine exactly what the
lesion was.
 By removing precancerous growths, such as actinic
keratoses, before they have a chance to become malignant
(squamous cell skin cancers), though, lasers are now
routinely being used as a preventative measure.
 Ablative lasers, such as the CO2 and erbium:YAG, are
generally chosen to remove these lesions.
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33. Vascular Lesions:
 Vascular lesions include broken blood vessels on the
face, unsightly spider veins on the legs, spider nevi,
hemangiomas, and certain birthmarks such as port
wine stains.
 For these types of skin irregularities, IPL is a common
choice, as it is minimally invasive.
 Also popular for treating these lesions are the pulsed
dye, Nd:YAG and diode lasers.
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34. Rosacea
 Rosacea is a common skin
condition that causes the blood
vessels in your face to become
visible and your face to appear
red or flushed. Patches of small,
pus-filled bumps are another
common symptom.
 Affecting over 16 million
Americans, rosacea doesn’t pose a
danger to your health, but it can
make you feel self-conscious
when your symptoms flare up.
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35. LASERS USED FOR ROSACEA
TREATMENT
• It is used to correct excess tissue that
can make the nose appear bulbous, a
symptom of phymatous (type 3) rosacea.
Erbium YAG
laser
• With this treatment, light is pulsed at an
optimal wavelength to penetrate vascular
lesions, or visible blood vessels.
Pulsed-dye
lasers
• Reshape nose or other parts of your face
if they have been scarred or enlarged by
rosacea-inflamed tissue
CO2 lasers
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36. COSMETIC APPLICATION
 There are two basic types of lasers used for cosmetic
purposes: ablative and nonablative.
 Ablative lasers actually vaporize the top layers of
damaged skin, while non-ablative lasers work deeper
in the skin without removing or otherwise damaging
the top layers.
 For this reason, there is no real patient downtime
associated with cosmetic procedures that employ
solely nonablative laser technology.
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37. SELECTIVE PHOTOTHERMOLYSIS
 Lasers are monochromatic (mono means one and chromo
refers to color), which means that a given laser emits
light of only one wavelength (or color) of light.
 Lasers work in cosmetic applications through a process
called "selective photothermolysis."
 When broken down, this very fancy word means that it
modulates the frequency of light (photo) to produce heat
(thermo) in the specific area of the corresponding thing
you wish to destroy (lysis).
 To do this, the wavelength of the light beam must be in
sync with the color of the target which is to be
addressed, whether that be brown spots, unsightly red
broken capillaries or some other undesirable skin
condition.
37

38. Fine Lines and Wrinkles
 For treating lines and wrinkles, a combination of skin
resurfacing and skin-tightening procedures can be
used or both can be accomplished with a more
aggressive ablative laser, such as a CO2 (carbon
dioxide) laser or Erbium lasers.
 The CO2 laser is also commonly used for the removal
of warts and skin tags and for cutting skin in laser-
assisted surgery.
 Pulsed dye lasers have also shown some success, along
with less aggressive nonlaser, light-based
treatments, such as IPL and LED photofacials
38

39. Skin Tightening
 Most cosmetic laser procedures provide at least some
level of superficial tightening because they produce a
controlled injury of the skin, which encourages
increased collagen production.
 For more significant tightening results, however, CO2
lasers are the laser of choice.
 In addition, there has been much success using
nonlaser, light-based treatments, such as Titan
infrared devices and Thermage radio-frequency based
systems
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40. PIGMENTED LESIONS
 The most commonly used lasers for the treatment of
pigmented lesions, such as sun spots, age spots,
melasma and other forms of hyperpigmentation are the
pulsed dye,1Nd:YAG, and fractional (Fraxel) lasers,
along with nonlaser, light-based treatments,
40

41. Tattoos
 The quality-switched laser and Nd:YAG remain popular
for tattoo removal, although some success can also be
had with the use of IPL.
41

42. Hair Removal
 The success and safety of laser hair removal is highly
dependent on the pigment present in both the skin and
the hair of the patient being treated.
 For darker-skinned patients, the Nd:YAG and diode
lasers are often the lasers of choice, and for lighter-
skinned patients, IPL has proved effective.
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43. Acne and Acne Scars
 For deeper acne scars, the CO2 laser remains the gold
standard, although more recent developments such as
the erbium:YAG, fractional laser and certain
nonablative lasers have shown considerable success
with superficial acne scarring.
 For the treatment of active acne, LED technology has
proven to be quite effective.
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