Treatment of alopecia areata with fractional photothermolysis laser.

Many studies have documented an abnormal cell-mediated immune reaction in alopecia areata (AA) 1 . The key histopatho logic feature of AA is a lymphocytic infiltrate around the lower hair follicle, which may appear in a characteristic “swarm of bees” pattern. The affected hair follicles terminate their anagen phase prematurely and regress via the induction of massive apoptosis of the lower portion of the follicle (the catagen phase), which results in a resting hair follicle (the telogen phase). The hair follicles may then reenter the anagen phase, but in the presence of a lymphocytic infiltrate, the anagen is terminated prematurely, which results in miniaturized hair follicles. AA represents a disorder of hair follicle cycling in a dual sense: it almost exclusively attacks anagen hair follicles and then greatly disturbs hair follicle cycling by “catapulting” anagen follicles into the catagen phase 2 . The treatment of AA depends on the severity and extent of the disease. The medications include a topical irritant, and in mild cases, topical and intralesional steroids. More aggressive therapy is used for severe cases, however, such as systemic corticosteroids, immunosuppressive drugs, and immune modulators 3 . These treatments frequently show side effects and a relatively high relapse rate, though. Recently, laser treatment of different wavelengths has been used to manage this roblem 1,3-