Effect of Superficial Hypothermic Cryotherapy With Liquid Nitrogen on Alopecia Areata

To the Editor.

—Alopecia areata (AA) is a common skin disease with no uniformly successful form of therapy. We report our recent experience showing that superficial hypothermic cryotherapy with liquid nitrogen appears to promote hair growth in AA.

Patients and Methods.

—A total of 112 outpatients with AA, whose hair loss covered less than 25% of the scalp, were randomly selected for participation in this study. The treated group had 41 men and 31 women (age range, 3 to 59 years), with a total of 237 lesions (range, 2 × 2 to 5 × 6 cm; average size, 3 × 4 cm). The duration of disease ranged from 3 days to 15 years. A cotton swab was used to lightly apply liquid nitrogen to the involved area, until it became just slightly frozen (about 2 to 3 seconds). After the frozen area thawed (about 2 to 3 seconds), a second