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Related Experiment Video

Updated: Jun 21, 2026

A New Technique for Quantitative Analysis of Hair Loss in Mice Using Grayscale Analysis

A New Technique for Quantitative Analysis of Hair Loss in Mice Using Grayscale Analysis

Published on: March 9, 2015

Temporal triangular alopecia with decreased follicular density.

C Y Silva¹, Y M Lenzy, L J Goldberg

¹Department of Dermatology, Boston University School of Medicine, Boston, MA, USA.

Journal of Cutaneous Pathology

|August 7, 2009

Summary

Temporal triangular alopecia (TTA) typically shows normal hair follicles. However, this study found a TTA patient with fewer hair follicles, expanding the known histologic spectrum of this hair loss condition.

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Area of Science:

Dermatology
Pathology

Background:

Temporal triangular alopecia (TTA) is a congenital hair loss condition affecting the temples.
Histologically, TTA is characterized by a normal number of small, non-inflamed hair follicles.

Observation:

This report details a case of TTA in a patient whose biopsy revealed a decreased number of hair follicles.
Most previous histopathologic studies of TTA used vertical sections, with limited studies using transverse sections.

Findings:

Contrary to typical findings, the patient's biopsy showed a reduced count of hair follicles.
This observation challenges the established histologic profile of TTA.

Implications:

The finding broadens the understanding of the histologic variations in TTA.
This expanded spectrum may offer new insights into the pathogenesis of temporal triangular alopecia.