Confocal reflectance mosaicing of basal cell carcinomas in Mohs surgical skin excisions

Abstract

Precise removal of basal cell carcinomas (BCCs) with minimal damage to the surrounding normal skin is guided by the examination of frozen histology of each excision during Mohs surgery. The preparation of frozen histology is slow, requiring 20 to 45 min per excision. Confocal reflectance mosaicing may enable rapid detection of BCCs directly in surgical excisions, with minimal need for frozen histology. Soaking the excisions in acetic acid rapidly brightens nuclei and enhances BCC-to-dermis contrast. Clinically useful concentrations of acetic acid from 10 to 1% require 30 s to 5 min, respectively. A tissue fixture precisely controls the stability, flatness, tilt, and sag of the excisions, which enables mosaicing of 36x36 images to create a field of view of 12x12 mm. This simulates a 2x magnification view in light microscopes, which is routinely used by Mohs surgeons to examine frozen histology. Compared to brightfield, cross-polarization enhances contrast and detectability of BCCs in the papillary dermis but not in the reticular dermis. Comparison of mosaics to histology shows that nodular, micronodular, and superficial BCCs are easily detected. However, infiltrative and sclerosing BCCs tend to be obscured within the surrounding bright dermis. The mosaicing method currently requires 9 min, and thus may expedite Mohs surgery.

Confocal microscopy to guide Erbium:yttrium aluminum garnet laser ablation of basal cell carcinoma: anex vivofeasibility study

“…Acetic acid condenses chromatin which increases backscatter from the nuclei, causing the nuclear morphology to appear bright (known as acetowhitening), which then enhances the contrast and detectability of BCCs in reflectance confocal images. 25 Initially, discarded Mohs tissue (containing BCC) was immersed in 5% acetic acid for 30 s and preablation imaging was performed. For imaging, we used a clinical confocal microscope [Vivascope 1500, Caliber Imaging and Diagnostics (formerly, Lucid Inc., Rochester)], with 830-nm illumination and a 30×, 0.9 numerical aperture gel immersion objective lens.…”

“…A more detailed description of the acetowhitening protocol, tissue mounting, and imaging and mosaicking process can be found in previous papers. 25,26 Acquisition of images and mosaics was performed for pre and postablation.…”

Review paper The use of reflectance confocal microscopy in selected inflammatory skin diseases

“…It has a wide range of applications, particularly in the diagnosis of neoplastic skin lesions, enabling non-invasive monitoring of treatment [2][3][4][5][6], in examining skin reactions to external factors (e.g. ultraviolet radiation) [7], as well as planning surgical margins in the course of pre-and intraoperative evaluation [8][9][10]. Reflectance confocal microscopy has also been applied in the study of a number of non-neoplastic skin diseases, especially inflammatory dermatoses.…”

Resin Tags Have No Contribution On Push-Out Bond Strength Of Self-Adhesive Resin Cement

“…Previous studies have already used CLSM to investigate the quality of endodontic fillings [27] and the penetration of sealers into the root dentin tissues [28]. However, the present investigation followed a methodology focused on dentin adhesion-an approach that revealed to be more adequate for the analysis of the quality of interfacial integrity [29].…”