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Updated: May 21, 2026

A New Technique for Quantitative Analysis of Hair Loss in Mice Using Grayscale Analysis
Published on: March 9, 2015
Circumscribed alopecia areata incognita
Jin Park1, Ki-Hun Song, Kyung-Hwa Nam
1Department of Dermatology, Chonbuk National University Medical School, Jeonju, Korea. airmd@jbnu.ac.kr
Abstract:
The characteristic lesion of alopecia areata is a smooth bald patch on the scalp. When there is no bald surface it is called alopecia areata incognita. To date, all cases of alopecia areata reported as so-called 'incognito' have shown a diffuse involvement of the scalp as in acute telogen effluvium. Recently, we have observed two patients who showed localised hair thinning of the scalp without bald spots. Histopathologically, the lesions were typical of alopecia areata with peribulbar lymphocytic infiltrates. The response to corticosteroid treatment and its clinical course were also compatible with alopecia areata.
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