Comparison of Two Kinds of Lasers in the Treatment of Acne Scars.

Acne scars are common and stigmatizing for the affected patients. Besides surgery, chemical peels, microdermabrasion, and microneedling, the treatment with fractional laser is a standard therapy. The results of reducing acne scars treated either with a fractional Er:YAG (erbium-doped yttrium-aluminum-garnet [Er:Y3Al5O1]) or a carbon dioxide (CO 2 ) laser at different wavelengths were compared and evaluated in the pilot study presented here. Fourteen patients with severe scars on both cheeks were treated four times in a random split-face approach: on one side with Er:YAG laser and on the contralateral side with CO2 laser following a standardized protocol. Therapeutic success was evaluated through the use of a high-resolution, 3D small-field capture system (PRIMOS), digital photography, and the Patient and Observer Scar Assessment Scale (POSAS) questionnaire. The evaluation was performed by a blinded investigator. Treatment results displayed a higher efficacy of the fractional CO2 laser compared with the Er:YAG laser as displayed by digital photographs. Additionally, objective (high-resolution, 3D small-field capture; PRIMOS) and subjective (POSAS) measuring results correlated positively in certain qualities (color, stiffness, thickness, surface, overall opinion). Using a novel scientific approach, we evaluated the therapeutic efficacy of different fractional lasers on acne scars using a rater-blinded approach. Compared with an Er:YAG laser, better skin smoothening was achieved by fractional CO2 laser treatment.