GI09 - Utility of Fluorescence Imitating Brightfield Imaging Microscopy for the Diagnosis of Feline Chronic Enteropathy

Abstract:

Background: Fluorescence Imitating Brightfield Imaging (FIBI) is a novel microscopy method allowing for real-time, non-destructive, slide-free tissue imaging of fresh, formalin-fixed, or even paraffin-embedded tissue. The non-destructive nature of technology permits tissue preservation for further downstream analysis.

Hypothesis/Objectives: To assess the utility of FIBI compared to conventional H&E-stained histology slides in feline gastrointestinal histopathology.

Animals: Formalin-fixed paraffin-embedded (FFPE) full-thickness small intestinal tissue specimens from 50 cases of feline chronic enteropathy (FCE).

Methods: Observational study. The ability of FIBI to evaluate predetermined morphological features (epithelium, villi, crypts, lacteals, fibrosis, submucosa, muscularis propria) and inflammatory cells was assessed on a 3-point scale (0 = FIBI cannot identify the feature; 1 = FIBI can identify the feature; 2 = FIBI can identify the feature with more certainty than H&E). H&E and FIBI images were also scored according to World Small Animal Veterinary Association (WSAVA) Gastrointestinal Standardization Group guidelines.

Results: FIBI identified morphological features with similar or in some cases higher confidence compared to H&E images (subscore 0.90). The identification of inflammatory cells was less consistent (subscore 0.48). FIBI and H&E showed an overall poor agreement with regards to the assigned WSAVA scores.

Conclusions and clinical importance: While FIBI showed an equal or better ability to identify morphological features in intestinal biopsy specimens, identification of inflammatory cells is currently inferior compared to H&E-based imaging. Future studies on the utility of FIBI as a diagnostic tool for non-inflammatory histopathologic lesions are warranted.