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Updated: Apr 26, 2026

A New Technique for Quantitative Analysis of Hair Loss in Mice Using Grayscale Analysis
Published on: March 9, 2015
Trichostasis spinulosa of the scalp mimicking Alopecia areata black dots
Flavianne Sobral Cardoso Chagas1, Aline Donati2, Isabella Ibrahim Doche Soares2
1Universidade Federal de Sergipe, Aracaju, SE, Brazil.
Abstract:
Alopecia areata is a common autoimmune disorder that leads to nonscarring hair loss. Black dots, also called comedo-like cadaver hairs, can be found in almost 50% of alopecia areata patients and indicate disease activity. Trichostasis spinulosa is a follicular disorder resulting from the retention of numerous hairs surrounded by a keratinous sheath in dilated follicles. Trichostasis spinulosa is a relatively common but underdiagnosed disorder of hair follicles. Here, we describe a man with alopecia areata of the eyebrows, androgenetic alopecia and trichostasis spinulosa at the vertex and show how dermoscopy can be useful in distinguishing black dots from Trichostasis spinulosa lesions.
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