Feature Characterization of Scarring and Non-Scarring Types of Alopecia by Multiphoton Microscopy

In 2018, a study utilized multiphoton microscopy (MPM) to differentiate between scarring and non-scarring alopecia in 5 normal subjects and 12 patients with alopecia, including 7 with non-scarring types (androgenetic alopecia and alopecia areata) and 5 with scarring alopecia (frontal fibrosing alopecia). The study found that MPM could identify smaller hair follicle diameters and the absence of sebaceous glands in scarring alopecia compared to non-scarring and normal subjects. Additionally, hair shafts were smaller in alopecia-affected scalps, with no significant size difference between non-scarring and scarring types. The presence of inflammatory cells was noted in scarring alopecia. The study concluded that MPM has the potential to non-invasively distinguish between scarring and non-scarring alopecia, which could help in monitoring and guiding treatment, though further validation is required.