FIBI (Fluorescence Imitating Brightfield Imaging) for rapid, slide-free dermatopathology

Background: Fluorescence Imitating Brightfield Imaging (FIBI) is a novel alternative microscopy method that can image freshly excised, non-sectioned tissue.We examine its potential utility in dermatopathology. Methods: Five skin samples embedded in paraffin blocks were superficially deparaffinized using xylene and ethanol and then briefly stained with hematoxylin and eosin (H&E). FIBI captured tissue surface histology images using simple microscope optics and a color camera. Subsequently, we applied deep learning-based models to improve resemblance to standard H&E coloration and contrast. FIBI images were compared to corresponding standard H&E slides and concordance was assessed by two dermatopathologists who numerically scored epidermal and dermal structure appearance and overall diagnostic utility. Results:The mean dermatopathologist scores indicate that FIBI images are equivalent to standard H&E slides for visualizing structures such as epidermal layers, sweat glands, and collagen. In addition, FIBI images were of diagnostic quality for most specimens including non-melanoma skin cancer and cysts. Conclusion: Images acquired with FIBI are comparable to traditional H&E-stained slides, suggesting that this rapid, inexpensive, and non-destructive microscopy technique, applicable to fresh tissue specimens, is a conceivable alternative to standard histology processes. Applications include time-sensitive procedures and settings with limited histology resources.