Diagnosis of lichen sclerosus based on multiphoton microscopy

Lichen sclerosus (LS) is a chronic inflammatory dermatosis that caused substarntial discomfort and morbidity. Early diagnosis and treatment can prevent the occurrence of squamous cell carcinoma (SCC). Multiphoton microscopy (MPM) has the potential as an effective, noninvasive diagnostic tool for tissues imaging at a molecular level. The technique has several advantages including deeper penetration depth and minimal photo-toxicity and photo-bleaching compared with other microscopy techniques. In this work, MPM was expand to histological investigations, differentiating LS lesion from normal skin by imaging unstained histological sections without hematoxylin and eosin (H and E) staining. Our results present that MPM has the ability to identify the characteristics of LS including the changes of hyperkeratotic epidermis, homogenized collagen, and inflammatory cell infiltration. These tissue architecture details are in perfect agreement with the corresponding H and E-stained images. In addition, the results of collagen content show significant difference in normal skin and LS. The studies indicate that the MPM technique not only has the ability comparable to the H and E-stained images to distinguish between normal tissue and LS, but also can provides more comprehensive diagnostic information for the pathologist. With the advent of the clinical portability of MPM, this technique has the potential to be a powerful tool for diagnosing LS and monitoring the treatment response in vivo.