Tortelly Violeta Duarte, Melo Daniel Fernandes, Ghedin Beatriz Serafim, Lima Caren Dos Santos, Garcia Thais Ura, Barreto Taynara de Mattos
Department of Dermatology, Marcílio Dias Hospital, Rio de Janeiro, Brazil.
Department of Dermatology, Pedro Ernesto University Hospital, State University of Rio de Janeiro, Rio de Janeiro, Brazil.
Skin Appendage Disord. 2020 Jan;6(1):48-51. doi: 10.1159/000504233. Epub 2019 Nov 26.
Pressure-induced alopecia (PA) is an unusual pattern of circumscribed hair loss that occurs after ischemic changes on the scalp. Trichoscopic findings described in the literature are scarce, nonspecific, and include black dots, broken hairs, circle hairs, and erythema. However, we report 3 cases of PA in which trichoscopy also showed many vellus and thin hairs. Possibly, the maintenance of these hair shafts may be explained by the more superficial insertion of their bulbs on the skin and/or their lower metabolic rates, making them suffer less from local hypoxia. Therefore, the authors suggest that these relevant signs should be added as a clue for the diagnosis of PA in doubtful cases.
压力性脱发（PA）是一种不寻常的局限性脱发模式，发生在头皮缺血性改变之后。文献中描述的毛发镜检查结果稀少且非特异性，包括黑点、断发、环形发和红斑。然而，我们报告了3例PA患者，其毛发镜检查还显示出许多毳毛和细发。这些毛干可能由于其毛囊球部在皮肤中插入较浅和/或代谢率较低，从而较少受到局部缺氧的影响，得以维持。因此，作者建议在可疑病例中应增加这些相关体征作为PA诊断的线索。
