Introduction: The Er:YAG laser, considered to be less effective than CO2 laser in its traditional form, in its new modulated version has variable pulse technology that is claimed to be superior to the earlier versions of the laser.
Aim: The aim of the study was to check efficacy and safety of the new variable square pulse (VSP) Er:YAG laser in the management of acne scar in patients with Fitzpatrick skin types IV and V.
Materials and methods: This retrospective study consisted of 80 patients (Fitzpatrick skin types IV and V) with atrophic and hypertrophic facial acne scars. Records of the patients who had undergone four treatment sessions with VSP technology equipped with Er:YAG laser were extracted. Each patient had undergone a minimum of four sessions. Fractional mode at medium laser pulse (SP) and long pulse (LP) was employed for the depressed center of the scars to stimulate neocollagenogenesis. Short laser pulse (MSP) in nonfractionated mode was used for ablating the raised scar border and hypertrophic scars. Goodman and Baron global scarring grading system was used for qualitative and quantitative assessments. Patient's satisfaction to the treatment and observer's assessment of improvement (based on photographs) was graded as poor (<25% improvement), fair (25-50% improvement), good (51-75% improvement), and excellent (>75% improvement).
Results: At the end of the four sessions, the number of patients in grade IV postacne scarring reduced from 16 to 2 and that in grade III from 47 to 29. The mean score significantly dropped from 36.94 to 27.5. Subjective assessment revealed that 78 of 80 patients had noticed more than 25% improvement, with 50 of them showing more than 50% improvement at the end of four sessions. Eight patients perceived an excellent response and 42 reported a good response. This is notably higher than the observer's grading, which showed an excellent response in only 2 patients and a good response in 35. Adverse effects were limited to prolonged erythema (two patients), prolonged crusting (one patient), and postinflammatory hyperpigmentation (one patient).
Conclusion: Ninety-seven percent of the subjects in our study perceived at least a fair improvement. We also saw a significant change in the objective score with a fall of the mean quantitative score from 36.94 to 27.15. This underscores the new variable-pulsed Er:YAG laser's effectiveness in the treatment of acne scars. It also has the added advantage of lesser adverse events and faster healing.
Keywords: Acne scars; modulated Er:YAG; variable pulse technology.