Subdermal carbon dioxide laser cutaneous contraction.

BACKGROUND Conventional carbon dioxide (CO(2)) skin laser resurfacing reverses the effects of photoaging. A recent clinical series reported the efficacy of performing subdermal CO(2)resurfacing to obtain the same skin contracture as epidermal skin resurfacing. OBJECTIVE To assess surface area contraction that occurs with subdermal CO(2) laser resurfacing in the rat model. DESIGN A nonrandomized control study was performed using 32 rats. The 3 test groups were divided by CO(2) laser strength (5 vs 7 W) and the pattern of resurfacing (cross-hatched vs parallel lines). MATERIALS AND METHODS The rats underwent subdermal continuous 2-mm defocused CO(2)beam treatment of the right-sided experimental flap. The left subdermal flap acted as a control. In the first group (n = 12), a subdermal cross-hatching of the subdermal flap was performed with 7 W. The second group (n = 10) was resurfaced in a parallel fashion with 7 W. The third group (n = 10) was resurfaced in a parallel fashion with 5 W. Measurements of skin area were taken immediately after laser resurfacing and 3 weeks after the treatment. RESULTS None of the treatment arms showed a change in skin surface area immediately or 3 weeks after treatment. In the first treatment group, all of the treated flaps showed an entire full-thickness slough. Of the controls, 75% showed minimal sloughing. The second and third experimental groups showed a 100% slough of the flaps. Of the 20 control flaps in the second and third groups, only 1 had a partial slough. CONCLUSIONS In this animal model, subdermal CO(2) laser resurfacing showed a 100% rate of skin sloughing. No change in skin surface area was evident immediately or 3 weeks after treatment.