TLDR Temporal triangular alopecia is a lifelong condition with hairless patches on the side of the head that may be present from birth.
Temporal triangular alopecia (TTA), also known as congenital triangular alopecia, is a condition that may be present at birth or noticed during the first decade of life, with uncertainty about whether it can develop after birth. It is characterized by lancet-shaped, hairless patches in the temporal region, which may be unilateral or bilateral, and persist for life. The condition has been associated with various congenital disorders and may be inherited as a paradominant trait. Histologically, TTA shows a normal or nearly normal total number of hair follicles, but almost all are vellus hairs with no significant inflammation or other abnormalities, and no fibrous "streamers" (stelae) as seen in androgenetic alopecia. Treatment is not usually required, but options include topical minoxidil, hair transplantation, or excision for cosmetic improvement. Diagnosis requires careful examination, as vertical sections alone are insufficient, and TTA can be mistaken for androgenetic alopecia if only upper dermal levels of horizontal sections are examined.
56 citations,
March 2010 in “Journal of Dermatology” Most cases of Temporal Triangular Alopecia are found in early childhood and may be related to genetic conditions.
14 citations,
January 2010 in “Dermatology” Some people with congenital triangular alopecia have a central tuft of hair in the bald patch, but the cause is unknown.
January 2010 in “Elsevier eBooks” The document concludes that different types of hair loss have specific treatments, and early diagnosis is crucial for preventing permanent hair loss.
69 citations,
January 2015 in “Current problems in dermatology” Trichoscopy is a quick, noninvasive method to diagnose hair and scalp disorders, often reducing the need for biopsies.
24 citations,
September 2014 in “Journal of the European Academy of Dermatology and Venereology” Trichoscopy is reliable for diagnosing Temporal Triangular Alopecia and can prevent unnecessary biopsies and wrong treatments.
122 citations,
April 1995 in “Journal of Cutaneous Pathology” The document describes how to tell different types of non-scarring hair loss apart by looking at hair and scalp tissue under a microscope.
3 citations,
January 2020 in “Clinical dermatology review” Trichoscopy is useful for diagnosing hair and scalp disorders in people with darker skin.
5 citations,
October 2012 in “Expert Review of Dermatology” Trichoscopy is a useful tool for diagnosing hair and scalp diseases without needing skin biopsies.