TLDR Horizontal scalp biopsy sections are better for diagnosing alopecia areata, showing fewer hair follicles and more miniaturized hairs.
In 2001, David A. Whiting's study on the histopathology of alopecia areata (AA) analyzed 494 scalp biopsies and highlighted the diagnostic benefits of using horizontal sections. The study found that AA patients had about 25% fewer follicles than controls, with an average of 30 hairs per 4 mm punch biopsy, including an abnormal terminal:vellus ratio of 1.3:1 and an anagen:telogen ratio of 62:38. Key histopathologic features of AA included peribulbar and intrabulbar mononuclear infiltrates, degenerative changes in the hair matrix, and increased numbers of miniaturized vellus hair follicles. The sex ratio of AA patients varied with age, and a 21% reduction in follicular counts was observed in patients aged 61-75. Alopecia universalis (AU) showed a 15% reduction in follicular counts compared to other AA types. Horizontal sections were deemed more useful than vertical sections for diagnosing and providing prognostic information in AA, particularly in cases lacking characteristic peribulbar inflammatory infiltrate.
64 citations,
July 1997 in “Journal of The American Academy of Dermatology” Finding eosinophils near hair bulbs helps diagnose alopecia areata.
89 citations,
October 1996 in “Dermatologic Clinics” Alopecia areata is likely caused by a combination of genetic factors and immune system dysfunction, and may represent different diseases with various causes.
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.
126 citations,
January 1987 in “Journal of The American Academy of Dermatology” The document concludes that understanding hair structure is key to diagnosing hair abnormalities and recommends gentle hair care for management.
122 citations,
November 1984 in “Journal of the American Academy of Dermatology” No single treatment is consistently effective for alopecia areata, and more research is needed.
January 2022 in “Indian Dermatology Online Journal” A man with total hair loss developed blackhead-like spots on his scalp, possibly because no hair was present to help drain oils.
January 2021 in “Indian journal of dermatopathology and diagnostic dermatology” Trichoscopy is a reliable method for diagnosing hair and scalp disorders quickly and non-invasively.
1 citations,
May 2016 in “Journal of the American Academy of Dermatology” The man likely has tufted folliculitis causing painful, scarring hair loss.
41 citations,
January 2014 in “Annals of Dermatology” Dermoscopic examination helps diagnose different types of hair loss conditions by showing specific patterns.
43 citations,
August 2013 in “Pediatric Dermatology” Trichoscopy is good for diagnosing and monitoring hair and scalp problems in children but needs more research for certain conditions.
245 citations,
March 2012 in “Journal of The American Academy of Dermatology” Dermatoscopy is useful for identifying different hair and scalp conditions and can reduce the need for biopsies.
