Ex vivo confocal microscopy: revolution in fast pathology in dermatology

Abstract

Summary Confocal microscopy with in vivo and ex vivo modalities has been used in the evaluation of skin cancer and other dermatological disorders. Recent developments in ex vivo confocal microscopy allow for faster pathology assessment with greater accuracy by the visualization of cellular and architectural details, similarly to standard pathology, in either paraffin‐embedded or frozen samples. They include the possibility of multimodal confocal microscopy using different lasers and fusion images. New staining protocols including immunostaining, with no damage to conventional histopathology preparation, have been recently described in melanocytic tumours and inflammatory skin diseases. Digital staining with haematoxylin and eosin is also incorporated in the new devices. In this review the applications of ex vivo confocal microscopy will be presented with the description of the technique and the technology, clinical evidence in dermatology and other fields, and further applications.

Exploring the utility of Deep Red Anthraquinone 5 for digital staining of ex vivo confocal micrographs of optically sectioned skin

“…Despite its somewhat nonspecific staining behavior, AO has been successfully employed as a nuclear staining agent to imitate hematoxylin in a rapidly growing number of studies on confocal imaging of fresh tissue [24]. However, the limitations of AO include staining of non‐nuclear structures and presence of unbound dye in the dermis.…”

“…While dermal fibers can be visualized because of their autofluorescence at 488 nm (vs 638 nm) in control unstained tissues, accentuation of dermal fibers (collagen, elastin) in AO images was prominently visible after staining, suggesting some degree of nonspecific staining. Histology correlation studies, as well as prospective clinical investigations to evaluate diagnostic accuracy (sensitivity, specificity, positive and negative predictive value), would be needed to definitively test and prove DRAQ5's enhanced diagnostic value relative to that of AO [24, 25].…”

Meibomian Glands or Not? Identification of In Vivo and Ex Vivo Confocal Microscopy Features and Histological Correlates in the Eyelid Margin

“…However, the epidermis of the eyelid is thinner than the rest, and it has a unique meibomian gland mechanism. Ex vivo CLSM has been used for rapid identification of skin tumor slices, but the diagnosis of the tumor tissue has not been used for eyelid tumors [ 26 ]; so, it is a promising research direction. The purpose of this study is to explore the imaging of the eyelid structure of normal people.…”

Clinical integration of fast Raman spectroscopy for Mohs micrographic surgery of basal cell carcinoma

“…Earlier work indicated a sensitivity and specificity of 88% and 99%, respectively [ 7 ], and a more recent diagnostic test of accuracy study (753 fresh Mohs specimens) reported a sensitivity of 79.8% and a specificity of 95.8%, when compared with frozen section histopathology [ 11 ]. Recent studies have shown that FCM images can be digitally coloured to appear similar to H&E sections [ 12 ]. Peters et al reported that BCC was identified with a 73% sensitivity and a 96% specificity in digitally coloured FCM images of 544 fresh specimens from 148 BCC excisions [ 13 ].…”