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Congenital Triangular Alopecia.

Vincent Chum Yin Li1, Paul Devakar Yesudian1

  • 1Department of Dermatology, Betsi Cawaladr University Health Board, Rhyl, United Kingdom.

International Journal of Trichology
|July 17, 2015
PubMed
Summary
This summary is machine-generated.

Congenital triangular alopecia (CTA) is a benign, nonprogressive hair loss typically affecting the frontotemporal scalp. This review confirms its common unilateral presentation and lack of gender predilection, aiding diagnosis.

Keywords:
Congenital triangular alopecianon-scarring alopeciatemporal alopecia

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Area of Science:

  • Dermatology
  • Trichology
  • Genetics

Background:

  • Congenital triangular alopecia (CTA), also known as temporal triangular alopecia, is a benign, nonscarring hair loss.
  • It typically presents as a triangular or lancet-shaped patch in the frontotemporal region, potentially present at birth or developing later.

Purpose of the Study:

  • To review the clinical presentation and diagnostic features of congenital triangular alopecia.
  • To analyze published case data regarding the prevalence and laterality of CTA.

Main Methods:

  • Literature review of 126 cases of CTA cited on PubMed from 1905 to 2015.
  • Analysis of patient demographics, clinical presentation, and diagnostic findings.

Main Results:

  • The majority of CTA cases (79%) presented with unilateral hair loss, while 18.5% showed bilateral involvement.
  • No significant gender predilection was observed.
  • Histological findings include miniaturized hair follicles and sparse vellus hair.

Conclusions:

  • CTA is a distinct, nonprogressive condition with characteristic clinical and trichoscopic findings.
  • Awareness of CTA aids in avoiding unnecessary investigations for nonscarring alopecia.
  • Follicular unit hair transplantation can offer cosmetic improvement if desired.