146 Six cases of Permanent Triangular Alopecia

SW. Park, JW. Kim, SW. Hwang, HY. Wang, HS. Sung. Dept. of Dermatology, In-Je University School of Medicine, Pusan, Korea

What we propose to term permanent triangular alopecia, first described by Sabouraud in 1905, is usually called congenital triangular alopecia or (congenital) temporal triangular alopecia. This is a kind of non-cicatricial alopecia that shows permanent alopecia without any change in the size of the scalp, especially the fronto-temporal suture and temporal areas. The shape of the alopecia is not always triangular, and sometimes it is Lancet-shaped or oval. This symptom is usually present at birth or just after, but several cases at around 6 years old and one at 27 have been reported. It is characterized by the fact that changes in shape or size does not occur over the lifetime of the patient. Since the lesion is clinically similar to alopecia areata, the possibility of unnecessary treatment caused by misdiagnosis is high. The only successful treatment is surgical excision or hair transplantation. Six patients (F/4, F/21, M/8, M/26, M/28, M/48) have been observed for the last 3 years. In the females it occurred bilaterally in the fronto-temporal suture area, and in males it occurred unilaterally in the occipital area of the 8-year-old boy and fronto-temporal suture area of the 3 men. The 8-year-old boy’s alopecia occurred when he was one year old and other 5 cases were observed at birth. Histopathologic examination of 5 cases including the 8-year-old boy revealed normal epidermis, vellus-like hair follicles and indeterminate follicles instead of mature follicles in the dermis. As the vast majority of lesions appear during the first 6 years of life and the lesions can also occur in the occipital region or any other scalp region, the authors suggest that the term permanent triangular alopecia is much more reasonable than that of congenital triangular alopecia or (congenital) temporal triangular alopecia.