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

Introduction: Few publications are available on eyebrow trichoscopy in patients with alopecia areata and frontal fibrosing alopecia (FFA).

Objective: To investigate the validity of using trichoscopy to examine eyebrow involvement in patients with lichen planopilaris (LPP) and FFA.

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 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 the zigzag type of FFA. Yellow dots, dystrophic hairs, hair regrowth in different directions, and diffuse empty follicles were associated with LPP activity and FFA severity.

Limitations: The retrospective nature of the statistical analysis.

Conclusions: Trichoscopy is a valid tool for evaluating eyebrow involvement in LPP and FFA. Thus, it could help increase the diagnostic accuracy and predict the prognosis of eyebrow hair loss at an early stage.