Application of confocal laser microscopy and its feasibility in routine diagnosis of surgical biopsy specimens

Handheld confocal laser endomicroscopy (CLE) enables an instantaneous assessment of the cellular morphology of different tumor types and margin assessment ex vivo. Here, we describe the correlation between CLE images and histology and the feasibility of incorporating this technology in assessing surgical biopsy specimens. A CLE microscope (Optiscan, ViewnVivo) acquired high-definition confocal images of surgical biopsy cases and a single autopsy case (15 canine, 1 feline, and 1 equine cases). Following minimal training on the imaging modality, 14 participants (6 anatomic pathologists and 8 anatomic pathology residents) were asked to assess 17 cases with and without signalment and clinical history. The CLE captured detailed cellular morphology and tissue microarchitecture in various surgical biopsy and select autopsy specimens. Averaging the diagnostic accuracy with and without clinical history, study participants were able to distinguish abnormal tissue in 15/17 cases, neoplasia from inflammation in 12/17 cases, and the cellular morphology of neoplasia in 8/13 cases. Across all questionnaires, there was a statistically significant improvement in the diagnostic accuracy when clinical history was provided (P-value: 3.07E-07 to .005, paired t-test). CLE enables the capture of the high-resolution microarchitecture of tissue and can be readily correlated to histology images. We demonstrated that with little training, anatomic pathologists could evaluate surgical biopsy specimens that can provide a rapid preliminary diagnosis and margin assessment.