Histopathologic Findigs of Normal Scalp and Alopecia Areata in Transverse Sections Jin Ho Chung,M.D., Hee Chul Eun, M.D.* Department of Dermatology, Capital Armed Forces General Hospital Seoul, Korea Department of Dermatology*, College of Medicine, Seoul National University, Seoul, Korea To observe the normal transverse histopathological findings of the follicles in the human scalp, a 4-or 6-mm punch biopsy specimen was taken from the normal scalp in 5 normal adults and 10 alopecia areata patients. We cbserved the normal transverse findings of the follicles in the transverse sections of normal scalps. The histopathological findings of the transverse sections taken from patches of 10 alopecia areata patients were also observed. The results were as follows ; 1) The follicular unit which usually consisted of 2-4 terminal follicles and I vellus follicle, sebaceous lobules and arrector pili muscles was observer in transverse section. The normal density of follicular units was about 0.62/㎣. 2) There were differences in the transverse sectional findings of the hair follicle according to levels, such as mode of keatinization in outer root sheath. 3) In the transverse section of the scalp biopsy specimen, it was possible to differentiate the various phases of the hair growth cycle. 4) The transverse sections of the patches in alopecia areata showed that 23%-100% of follicles were in telogen stage. 5) The observation of transverse sections of scalp biopsy specimen seems to be a useful method in the histopathologic study of the hair follicle disorders particularly alopecia areata.