Laser Scar Removal

Lasers in the field of resurfacing have been of limited utility in the brown skin Downtime, and post inflamatory pigmentation, have been the major problems

Resurfacing in India

Resurfacing lasers have traditionally been used for wrinkles in the west In India, more important indications are acne scarring, chicken pox scarring, pigmentation and it they can work, strech marks

Ablative Skin Resurfacing

Existing treatments were either too mild( such as MDA/sup chemical peels) or too aggressive (such as dermabrasion/CO2 resurfacing)

Fractional photothermolysis

In 2003, Manstein and colleagues introduced the concept of fractional photothermolysis to bridge the gap between ablative and nonablative resurfacing. Manstein D, Herron GS, Sink RK, et al. Fractional photothermolysis:a new concept for cutaneous remodeling using microscopic patterns of thermal injury. Lasers Surg Med2004;34:426–38.

2940nm Er:YAG Pixel


skin is treated in fractions (hence the name fractional photothermolysis) or pixels (skin is divided in to zones or pixels,just like a digital camera), thereby removing tissue by scattered ablation( destruction), in contrast to the total ablation done by previous lasers

PixelTM Fractional Laser Resurfacing


The total collateral microdamage depends on the number of passes, matrix,size, and the level of energy used.


The Pixel thus treats only a small fraction of the skin (about 25-35%), and leaves the rest of skin unaffected( see figure below). This generates a pattern of microscopic noncontiguous columns of thermal injury within the dermis.

Level : epidermis superior dermis Biopsy: 0h; immediately after


Coagulation of the epidermis and superior dermis


Fractional Laser Resurfacing


7 days After Pixel-rapid repithelialization


Normal epidermis and inflammatory infiltrate in the dermis Little risk of infeciton/pigmentation/scarring minimum down time

The Laser Swing
Laser Skin Resurfacing: Past, Present and Future


Fractional / Non Fractional Lasers Water Absorption Graph


Pixel 2940nm laser Specifications

Laser Type: Er:YAG
Wavelength: 2940nm
Pulse duration: 1, 1.5, 2 msec
Number of Pixels: 49 or 81 dots/ cm2
Treatment Area: 11 x11mm
Beam Delivery: Direct
Maximum Pulse Energy: 1400mJ/Pulse
Maximum Pixel Energy:
17 mJ/Pixel (81 dot Pixel size)
28 mJ/Pixel (49 dot Pixel size)
Repetition rate: 2 Hz
The single-pass ablation microzone of each pixel measures approximately 150 mm in diameter and 120–140 mm in depth

Pixel Technology Spot Size



scar-1a  scar-1b

scar-2a  scar-2b

scar-3a  scar-3b

scar-4a  scar-4b

scar-5a  scar-5b

Our experience

  • Our patient population is mostly acne scars
  • Some patients of ageing changes, other scars, pigmentation conditions- melasma, lichen planus pigmentosus, frictional melanosis
  • Others: Keratosis pilaris, Becker’s nevus

Our methods

  • Informed consent after viewing a brochure and computer presentation
  • The informed consent form mentions that multiple sessions are needed
  • That some erythema may occur which may persist fro 2-5 days
  • All patients are usually treated with prior bleaching agents and sunscreens

Methods n=67

  • All acne scars are graded: grade 1-4( modified Goodman scale); type also noted
  • Discomfort during treatment is graded as comfortable/ slightly uncomfortabel/ very uncomfortable
  • Post procedure reaction graded by patient as mild( erythema of one day) , moderate (erythema(1-5 days), severe( more than 5 days)
  • Improvement graded as mild( <25%), moderate(25-50%), very good(50-75%) , excellent(more than 75%)

Patient feedback on treatment

  • Most patients comfortable during treatment
  • Describe it as mild tingling
  • Some patients wanted a break during treatment due to feeling of heat
  • 5 patients demanded EMLA
  • Ice packs needed for all, particularly when multiple passes are used

Pixel laser(n=67)

  • ten patients were not available for follow up
  • Of the 57 patients: Male – 31 ( 18 – 48 yrs ) Female -26 ( 17 – 48 yrs )
  • Out of 10 who had dropped out, 4 said they were happy with one just pass; 3 were unhappy because of the erythema ; 3 felt the cost was too high

All patients became fairer

  • Clinical improvement was atleast 51% to 75% in 80% of the patients after 4 sessions.
  • Most patients with superficial and medium depth scars responded very well
  • Deep scars did not respond in terms of depth, but had a textural improvement and change in colour

Postoperative changes

  • At low dosage( 700-800 mj) erythema lasts only a day
  • Erythema lasts longer when multiple passes are used and when higher dosages( 1200-1400 ) are used
  • At 1400 mj, erythema lasted almost a week; two patients also had mild crusting and pigmentation