Fractional CO2 laser for the treatment of acne scars.

BACKGROUND:   Numerous reports have been published on skin rejuvenation by the so-called fractional laser device that delivers a laser beam in a dot form over a grid pattern.

AIMS:   In this study, we characterized the effects of a fractional CO(2) laser on atrophic acne scars at the clinical and ultrastructural levels.

METHODS:   Seven healthy adult Japanese volunteers (aged 32-46 years, mean 37.6, five men and two women of Fitzpatrick skin type III) were recruited for this study. A fractional CO(2) laser device, SmartXide DOT (DEKA, Florence, Italy), was used with irradiation parameters set as follows: output power 10 W, pulse width 600 μs, dot spacing 800 μm, and stack 2 (irradiation output power 0.91 J/cm(2) ). A clinical examination and punch biopsy of each subject was performed before and just after the irradiation, and also at week 3 after three irradiation sessions. The biopsy specimens were stained with toluidine blue and were examined ultrastructurally.

RESULTS:   Clinical improvement of the atrophic acne scars was observed at week 3 after the third irradiation session in all cases compared with the condition before treatment. Histologically, outgrowths of many degenerated elastic fibers were observed as irregular rod-shaped masses in the superficial dermis prior to the treatment in the region of the acne scars. At week 3 after the third irradiation, the degenerated elastic fibers were no longer observed, and the elastic fibers were elaunin-like.

CONCLUSIONS:   The fractional CO(2) laser is considered to be very effective for treating atrophic acne scars.