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Published on: October 25, 2018
Subdermal Laser-Assisted Scar Subcision (SLASS) Combined With Fractional CO2 Laser for Acne Scars: Efficacy
Adrián Alegre-Sánchez1, Ana Suárez-Valle1, Diego Fernández-Nieto1
1Dermatology Clinic AB Derma, Madrid, Spain.
Background:
Rolling atrophic acne scars attach the deeper dermis to the muscular-fascial layer with a fibrous component. Subcision is the most commonly used treatment technique for rolling scars.
Aims:
Our objective is to describe the efficacy and safety profile of a new type of subcision: the "subdermal laser-assisted scar subcision" (SLASS), using a 1470-nm diode fiber laser in combination with ablative fractional CO2 laser.
Patients/Methods:
A retrospective study of the combination of subcision with subdermal laser and CO2 fractional laser in one session for 42 patients is presented. For the subcision, 400-μm fibers of a 1470-nm diode laser were used with energies ranging from 100 to 200 J per 2 cm2 area, using 3-4 W of power and pulsed mode with 15-25 ms pulses. After subcision, CO2 fractional laser was performed with different settings depending on the deepness of the scars: 40-50 W power peak, 1-1.5 ms dwell time, and 20%-30% density.
Results:
Mean reduction of the ECCA grade scale before and after treatment was of 92.6 ± 34.3 points (p < 0.05). Considering SCAR-S scale, ranging from 0 to 5 (0 = clear; 5 = very severe), a mean improvement of 1.67 points was obtained (p < 0.05). Significant differences were found in both ECCA scale and SCAR-S scale before and after treatment. None of the patients had severe adverse effects after the procedure.
Conclusions:
SLASS subcision can be considered as a promising technique for rolling acne scars. It provides a thermo-mechanical subcision effect to the scarred area compared with traditional subcision techniques. CO2 laser seems effective and safe.

