P171 : Trichoscopic findings in androgenetic alopecia and alopecia areata

Background: The use of trichoscopy can ease the division of various hair loss disease by magnifying the scalp and structure of hair. Objectives: Our purpose is to measure the frequency of representative trichoscopic findings in Alopecia areata(AA) and Androgenetic alopecia(AGA) patients of Korea and the frequency of various trichoscopic findings depending on the severity based on BASP classification. Methods: A retrospective cohort review of total 87 patients with AGA(n=57) and AA(n=30) between 2014-2015 at Kangbuk Samsung Hospital. Three dermatologists judged the trichoscopic findings (hair shaft, hair follicle opening, perifollicular epidermis) in 87 patients. Results: In this study, vellus hair is observed 21/30 cases (70%) in AA patients and 20/57 cases (33%) in AGA patients. In AGA patients, as severity of hair loss increases, the portion of patients with vellus hair, thickness heterogeneity, honeycomb pigmentation also increases (p < .05). Also, in AA patients, as severity increases, the portion of patients with black dot and perifollicular sign increases (p < .05). Conclusion: Trichoscopy is very useful in diagnosis between AA and AGA if it is difficult to diagnosis by naked eyes. Also hair loss disease’s severity can be assessed by trichoscopy.