Assessment and Validity of Trichoscopy for Eyebrow Involvement in Lichen Planopilaris: A Case-Control Study

Introduction: Few publications are available on eyebrow trichoscopy in patients with alopecia areata and frontal fibrosing alopecia (FFA). Objective: We aimed to investigate the validity of using trichoscopy to examine the eyebrow involvement in patients with lichen planopilaris (LPP) and its variants. Methods: In this case control study, 109 patients with eyebrow involvement in LPP and FFA (cases) and with acquired hair disorders of the eyebrows (controls) were included. Results: Trichoscopy was highly specific and sensitive for the diagnosis of LPP and its variants, including FFA. Trichoscopic features significantly associated with LPP were peripilar scaling, peripilar pigmentation, broken hairs, peripilar white halos, diffuse empty follicles, and vellus hair. Localized peripilar erythema and empty follicles were significantly associated with the diffuse form of LPP and zigzag-type FFA. Yellow dots, dystrophic hairs, regrowth in different directions, and diffuse empty follicles were associated with LPP activity and FFA severity. Conclusions: Trichoscopy is a valid tool for evaluating eyebrow involvement in LPP. Thus, it could help increase the diagnostic accuracy and predict the prognosis of eyebrow hair loss at an early stage.