Pressure alopecia, also known as postoperative alopecia, and pressure-induced alopecia,[1] occurs in adults after prolonged pressure on the scalp during general anesthesia, with the head fixed in one position, and may also occur in chronically ill persons after prolonged bed rest in one position that causes persistent pressure on one part of the scalp, all likely due to pressure-induced ischemia.[2]: 762
Pressure alopecia usually manifests as a skin-colored hairless patch on the occiput. Hair loss usually becomes noticeable 3-28 days after the initial trigger. Depending on the severity of ischemia pressure alopecia can be scarring or non-scarring.
Pressure alopecia is diagnosed based on clinical history and the symptoms. Treatment is usually not needed because the condition spontaneously resolves within months.
Signs and symptoms
Pressure alopecia typically affects the occiput and manifests as a distinct area that is bald and skin-colored.[3] Other symptoms include swelling, erythema and tenderness.[4]
Hair regeneration takes place between one and four months following the triggering incident, with hair loss often becoming apparent three to 28 days later. A patient may experience nonscarring or scarring alopecia, depending on the severity of pressure-induced tissue ischemia.[5]Alopecia that is not scarred is the outcome of milder ischemia, while alopecia that is scarred is the consequence of persistent ischemia that causes ulcer formation.[6]
Clinical criteria such as the development of alopecia in the occiput and ulceration or scarring, along with a usual history of protracted surgery or immobility, are used to diagnose pressure alopecia.[5]
Treatment
Because the condition is typically self-limited and reversible, treatment is not usually required.[4]
Outlook
Pressure alopecia is usually reversible, with hair growing back in a few months.[5]
^Rapini, Ronald P.; Bolognia, Jean L.; Jorizzo, Joseph L. (2007). Dermatology: 2-Volume Set. St. Louis: Mosby. ISBN1-4160-2999-0.
^James, William; Berger, Timothy; Elston, Dirk (2005). Andrews' Diseases of the Skin: Clinical Dermatology. (10th ed.). Saunders. ISBN0-7216-2921-0.
^Lee, Won‐Soo; Lee, Se‐Won; Lee, Sanghoon; Lee, Jin Wook (2004). "Postoperative Alopecia in Five Patients after Treatment of Aneurysm Rupture with a Guglielmi Detachable Coil: Pressure Alopecia, Radiation Induced, or Both?". The Journal of Dermatology. 31 (10). Wiley: 848–851. doi:10.1111/j.1346-8138.2004.tb00614.x. ISSN0385-2407.
^ abCorona-Rodarte, Eduardo; Cano-Aguilar, Luis Enrique; Baldassarri-Ortego, Luisa Fernanda; Tosti, Antonella; Asz-Sigall, Daniel (2024). "Pressure alopecias: A review". Journal of the American Academy of Dermatology. 90 (1). Elsevier BV: 125–132. doi:10.1016/j.jaad.2023.07.009. ISSN0190-9622.
^Ravaioli, Giulia Maria; Starace, Michela; Alessandrini, Aurora Maria; Guicciardi, Federica; Piraccini, Bianca Maria (2019). "Pressure alopecia in pediatric and adult patients: Clinical and trichoscopic findings in 12 cases". Journal of the American Academy of Dermatology. 81 (4). Elsevier BV: 1021–1023. doi:10.1016/j.jaad.2019.02.050. ISSN0190-9622.
^Loh, Seung-Hee; Lew, Bark-Lynn; Sim, Woo-Young (2015). "Pressure alopecia: Clinical findings and prognosis". Journal of the American Academy of Dermatology. 72 (1). Elsevier BV: 188–189. doi:10.1016/j.jaad.2014.07.047. ISSN0190-9622.