The 100 Most-Cited Publications in Lichen Planopilaris: A Bibliometric Analysis

Introduction: Lichen planopilaris (LPP) is a rare scarring alopecia with poorly understood etiology, leading to challenges in both diagnosis and management. With an increasing number of studies focused on its clinical presentation, histopathology, and trichoscopic features, a comprehensive bibliometric analysis of high-impact LPP research is necessary to assess current trends and identify gaps in the literature. Methods: The objective of this study was to analyze trends in LPP research using the top 100 most-cited articles from Web of Science. Results: The average number of citations per article was 80.4 (range: 37–289), with publication dates ranging from 1990 to 2021. The most-cited article was Kossard’s “Progressive Frontal Scarring Alopecia in Postmenopausal Women” with 289 citations. The USA (n = 47) had the most publications, followed by England (n = 18) and Spain (n = 14). Most articles were LOE 3 (n = 34) focusing on the “clinical and histopathological presentation” (n = 33). Key reported trichoscopic features included perifollicular erythema, perifollicular scaling, and loss of follicular ostia. Conclusion: This bibliometric analysis highlights foundational LPP studies, emphasizing key trichoscopic features while revealing gaps in high-level evidence. It underscores the need for more rigorous research and expanded geographic diversity to enhance diagnostic markers, refine trichoscopic criteria, and improve therapeutic approaches.

Lichen planopilaris (LPP) is a rare, scarring hair loss disorder that primarily affects women between the ages of 40 and 60. LPP leads to permanent hair loss by triggering an immune reaction against hair follicles, though the underlying mechanisms remain unclear. LPP includes several subtypes, such as frontal fibrosing alopecia, which is characterized by hairline recession, and Graham-Little syndrome, which affects both scalp and body hair. Diagnosing LPP can be challenging due to its similarity to other conditions, requiring a combination of clinical evaluation, tissue analysis, and increasingly, dermoscopy – a noninvasive method for examining the scalp. This bibliometric analysis examined the 100 most-cited research articles on LPP to identify influential studies, emerging trends, and knowledge gaps. The analysis revealed that most studies focus on clinical presentation and tissue analysis findings, while high-level evidence remains scarce. Notably, trichoscopy, a dermoscopic technique, is becoming an important tool for diagnosing LPP, with key features like redness around hair follicles and loss of follicular openings frequently reported in the literature. However, a lack of standardized terminology and limited research on darker skin types present challenges in clinical practice. The study highlights the need for further research to standardize diagnostic criteria, improve treatment outcomes, and include a more diverse range of patient populations. Expanding the geographical and linguistic scope of LPP research could help address these gaps, ultimately improving the diagnosis and management of this complex disorder.