Cryotherapy Versus Fractional Carbon Dioxide Laser in Patchy Alopecia Areata: A Self-Controlled Comparative Study

This study evaluated the efficacy and safety of cryotherapy and fractional carbon dioxide (FCO2) laser treatments for patchy alopecia areata (AA) in 22 patients. Both treatments were significantly more effective than no treatment, with FCO2 laser achieving an excellent response in 7 patches and cryotherapy achieving a moderate to excellent response in 12 patches. There was no significant difference in effectiveness between the two treatments. A negative correlation was found between patient age and improvement with FCO2 laser, suggesting older patients experienced less improvement. Both treatments effectively reduced black dots, yellow dots, and exclamation mark hairs, with FCO2 laser also increasing short vellus hairs. Minimal side effects were reported, and 54.5% of patients preferred FCO2 laser therapy. The study highlights the potential of FCO2 laser as an effective treatment for AA with fewer side effects, although the small sample size is a limitation.