Therapeutic Effect of Superficial Cryotherapy on Alopecia Areata: A Prospective, Split-scalp Study in Patients with Multiple Alopecia Patches

Background Alopecia areata (AA) affects anagen hair follicles resulting in non-scarring hair loss. Since its introduction, superficial cryotherapy has been used as one of the meaningful treatment modalities for AA. Objective The purpose of this study is to clarify the therapeutic efficacy and safety of superficial cryotherapy for treatment of AA. Methods In 19 patients with multiple bilateral AA patches on their scalp, superficial cryotherapy was performed on the right side, every 2 weeks. Prednicarbate 0.25% solution was applied twice a day to both the treated and the control sides. Clinical improvement was estimated using the Severity of Alopecia Tool (SALT) score by 3 different dermatologists, along with the changes in terminal and vellus hair count and hair thickness analyzed by phototrichogram. Results After 4 months of treatment, mean terminal hair count on the right scalp was 1.6-fold increased (p=0.005), while mean terminal hair count on the left scalp showed no significant change (110.1% increase, p=0.285). Mean SALT score decrease on the right was 4-fold greater than that on the left (40.7% and 9.6%), without statistical significance (p=0.282). Mean vellus hair count and mean hair thickness did not show significant changes after superficial cryotherapy. No remarkable adverse event was observed. Conclusion Superficial cryotherapy is an efficacious treatment modality with advantages of simplicity and noninvasiveness. It can be considered as a meaningful therapeutic modality for AA, especially when the disease status is limited to minimal to mild, or the conventional AA treatment is not applicable.