Ex vivo confocal microscopy: an emerging technique in dermatology

Abstract

This review aims to give an overview of the current available applications of ex vivo confocal microscopy (EVCM) in dermatology. EVCM is a relatively new imaging technique that allows microscopic examination of freshly excised unfixed tissue. It enables a rapid examination of the skin sample directly in the surgery room and thus represents an alternative to the intraoperative micrographic control of the surgical margins of cutaneous tumors by standard microscopic examination on cryopreserved sections during Mohs surgery. Although this technique has mainly been developed for the margin’s control of basal cell carcinoma, many other skin tumors have been studied, including melanoma. Use of EVCM is continuing to evolve, and many possible applications are under investigation, such as the study of nails and hair diseases and the diagnosis of skin infections.

Diagnostic accuracy of a new ex vivo confocal laser scanning microscope compared to H&E‐stained paraffin slides for micrographic surgery of basal cell carcinoma

“…In addition to specific removal and cutting techniques similar to the ‘Tuebinger Torte’ and the ‘Muffin Technique’, histological inspection is consistently enhanced as well. As an alternative to paraffin or frozen sections, other techniques for histopathology have been developed, such as in vivo or ex vivo optical coherence tomography (OCT), rapid lump examination (RLE) and confocal laser scanning microscopy (CLSM) …”

Ex vivo confocal laser scanning microscopy for bullous pemphigoid diagnostics: new era in direct immunofluorescence?

“…Ex vivo CLSM is an emerging diagnostic technique, which offers real‐time, rapid imaging of the freshly excised or frozen skin at the cellular level. It has been successfully applied to the perioperative evaluation of melanocytic and non‐melanocytic skin tumours as an additional method for Mohs microscopic surgery; however, many possible new indications for ex vivo CLSM are under investigation . Recently, our group performed ex vivo CLSM examination of melanoma and basal cell carcinoma samples using FITC‐labelled S‐100, melan‐A and Ber‐EP4 antibodies and detected the selective binding of the antibodies to the tumour cells .…”

“…The main advantages of ex vivo CLSM include the vertical scanning of tissues and the lack of a limited vertical penetration depth, as opposed to in vivo CLSM. The resulting high‐resolution, vertical images, which are identical to conventional histopathology sections, enable the examination of all skin layers . Furthermore, it allows the utilization of fluorescent stains, which increase the contrast between cellular/tissue compartments …”

“…The resulting high-resolution, vertical images, which are identical to conventional histopathology sections, enable the examination of all skin layers. 1 Furthermore, it allows the utilization of fluorescent stains, which increase the contrast between cellular/tissue compartments. 2 So far, ex vivo CLSM has been mainly used in the intra-and postoperative assessment of skin tumours, the control of surgical skin margins and as an assistive method for Mohs microscopic surgery.…”

Ex vivo confocal laser scanning microscopy: An innovative method for direct immunofluorescence of cutaneous vasculitis

“…It provides real‐time examination of all skin layers through vertical scanning of skin samples. Optical sectioning of high‐resolution digital images, similar to conventional histology, enables rapid assessment of freshly excised tissues . Moreover, it allows fluorescence detection in the tissue through the application of fluorescence stains and offers an alternative method to conventional fluorescence detection systems in the diagnosis of skin lesions .…”