The use of non-ablative fractional resurfacing in Asian acne scar patients.

BACKGROUND AND OBJECTIVES: Non-ablative fractional resurfacing (NA FR) has been shown to be effective for photorejuvenation and acne scarring. Previous studies indicated that density, more than pulse energy, was associated with post-inflammatory hyperpigmentation (PIH) in Asians. The objective of this retrospective study was to assess the efficacy and complications of eight passes of NA FR ('full-NA FR') with the 1,550 nm erbium-doped fibre fractional laser (Fraxel SR laser system, Solta Medical, Hayward, CA) versus four passes ('mini-NA FR') with comparable pulse energy and treatment level as 'full-NA FR', but double the number of treatment sessions in Asian acne scar patients.

MATERIALS AND METHODS: Forty-seven Asian atrophic facial acne scar patients who received full-face full-NA FR or mini-NA FR treatments between December 2005 and February 2009 were included. All photographic images captured with the Canfield Visia CR system at baseline and follow-ups were assessed for clinical efficacy and complications by an independent, non-treating and blinded physician.

RESULTS: The total treatment densities for full-NA FR and mini-NA FR were 442.5 and 210.5 MTZ/cm(2), respectively. For full-NA FR, the PIH risk was 18.2% with cross-polarized images compared to 6.0% for mini-NA FR. This difference was statistically significant (P < 0.001). Improvement in skin texture, acne scarring, enlarged pores and overall pigmentation irregularity all reached statistical significance at last follow-up compared to baseline. There was no statistically significant difference in clinical efficacy between three full-NA FR and six mini-NA FR treatments.

CONCLUSIONS: NA FR was effective and safe in Asians. By reducing the number of passes and the total treatment density, the risk of PIH could be reduced. Meanwhile, clinical efficacy could be maintained by increasing the total number of treatment sessions.