Trichoscopic Features of Lichen Planopilaris Versus Frontal Fibrosing Alopecia: A Systematic Review

This systematic review compares the trichoscopic features of Lichen Planopilaris (LPP) and Frontal Fibrosing Alopecia (FFA), analyzing 33 articles. It identifies distinct dermoscopic features for each condition: early LPP shows peripilar cylindrical casts and perifollicular redness with arborizing vessels, while active FFA is characterized by yellow dots, perifollicular erythema, and scattered pigmentation. Both conditions exhibit shiny white areas in inactive stages. Late LPP presents with a target arrangement of blue-grey dots and irregularly arranged white fibrotic dots, whereas late FFA is marked by black dots, lonely hairs, and loss of vellus hairs. Some features, like blue-grey structureless areas, are nonspecific. The review emphasizes the importance of correlating dermoscopic features with histopathological findings to differentiate between LPP and FFA.