背景：中央离心瘢痕性脱发（CCCA）命名法描述了瘢痕性脱发的典型临床表现，始于顶点头皮，对称，和离心演化。然而,作者在临床上注意到了非典型表现,并在文献中进行了报道.
目的：我们试图描述已发表的CCCA成年患者脱发的分布特征。
方法：使用三步搜索过程来评估CINAHL中的研究文章，EMBASE,谷歌学者，MEDLINE,Scopus,和WebofScience数据库。包括头皮摄影或脱发分布描述的研究。三名研究人员评估了符合条件的临床亚型研究。PRISMA扩展范围审查（PRISMA-ScR）用于报告结果。
结果：纳入了由281例CCCA组成的99项研究。脱发分布包括经典演示文稿的变体以及不同的亚型，如斑驳，枕骨,顶叶,额叶,temporal,和trichorrhexis。
结论：研究具有显著的同质性，正如CCCA的经典分布被普遍报道。此外,临床诊断病例可能有并发诊断，和许多研究没有报告的结果。
结论：CCCA术语可能并不总是反映临床表现。了解非典型表现对于告知适当和有针对性的治疗至关重要。
BACKGROUND: Central centrifugal cicatricial alopecia (
CCCA) nomenclature describes a typical clinical presentation of cicatricial hair loss that begins on the vertex scalp with progressive, symmetric, and centrifugal evolution. However, atypical presentations have been noted clinically by the authors and reported in the literature.
OBJECTIVE: We sought to characterize the distribution of hair loss in published cases of adult patients with
CCCA.
METHODS: A 3-step search process was used to evaluate research articles in Cumulative Index to Nursing & Allied Health, EMBASE, Google Scholar, MEDLINE, Scopus, and Web of Science databases. Studies with scalp photography or description of hair loss distribution were included. Three researchers evaluated eligible studies for clinical subtypes. Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping
Review was used to report results.
RESULTS: Ninety-nine studies consisting of 281 cases of
CCCA were included. Hair loss distributions included variants of the classic presentation along with distinct subtypes such as patchy, occipital, parietal, frontal, temporal, and trichorrhexis.
CONCLUSIONS: Studies had significant homogeneity, as the classic distribution of CCCA was commonly reported. Additionally, clinically diagnosed cases may have concurrent diagnoses, and numerous studies did not report trichoscopy findings.
CONCLUSIONS: CCCA terminology may not always be reflective of clinical presentation. Understanding atypical presentations is essential to inform appropriate and targeted treatment.
