Optical coherence tomography and confocal laser scanning microscopy as non-invasive tools in the diagnosis of sinonasal inverted papilloma: a pilot study

Abstract

Optical coherence tomography (OCT) and confocal laser scanning microscopy (CLSM) are light-based imaging techniques that allow for a visualization of microscopic tissue properties in vivo. Our study was to examine whether they allow for differentiation of inverted papilloma (IP) from nasal polyps (NP). Five cases of IP and NP, respectively, were investigated intraoperatively with OCT and CLSM. Biopsies were taken of the investigated area and were analyzed ex vivo with OCT and CLSM and then underwent HE-staining for standard light microscopy. On OCT images, IP showed the characteristic inverted character of the epithelium, that was thicker with a high degree of variability of thickness compared to the thin and homogenous epithelium of NP. In addition, the characteristic stromal edema of NP could be visualized. On CLSM images, the typical epithelial invaginations of IP appeared as crypts, while in NP the highly organized cylindric epithelium could be visualized. In vivo, OCT acquired images of sufficient quality to visualize these characteristics, while CLSM did not. Our study demonstrates that OCT and CLSM can distinguish IP from NP. Further technical development is required to apply the techniques clinically to guide intranasal biopsies or even to make them dispensable.

Fluorescence grid analysis for the evaluation of piecemeal surgery in sinonasal inverted papilloma: a proof-of-concept study

“…Therefore, we validated the FMI by correlating ex vivo imaging of FFPE blocks with H&E histopathology and target expression (i.e., VEGF-A immunohistochemistry). Earlier, it has been shown that the processing of tissue does not alter relative differences in fluorescence between target and uninvolved tissues [28],…”

“…Therefore, we validated the FMI by correlating ex vivo imaging of FFPE blocks with H&E histopathology and target expression (i.e., VEGF-A immunohistochemistry). Earlier, it has been shown that the processing of tissue does not alter relative differences in fluorescence between target and uninvolved tissues [ 28 ], suggesting that the fluorescence grid analysis can help in evaluating FMI for clinical use, thereby providing substantiated go/no-go decisions in phase I/II studies. We ascertained that the standard method of evaluating FMI for wide local excisions is not preferable for piecemeal surgery since it masks the (substantial) variability present in the imaging data as only two ROIs (i.e., target and background) are obtained per FFPE block.…”

Risk Factors for Recurrence after Surgical Resection of Sinonasal Inverted Papilloma

“…The use of optical coherence tomography and confocal laser scanning microscopy, as well as high-resolution microendoscopy using a specific contrast agent, proflavine, are being proposed for the differentiation of the SNIP from nasal polyps. 21,22 Li et al 23 have also found that the Storz Professional Image Enhancement System (SPIES) is a rapid and noninvasive live-imaging technique that can detect the SNIP by examining the sinonasal mucosa and the submucosal and micro vasculature. These techniques have shown promising results, but their roles remain to be confirmed.…”

In Vivo Confocal Scanning Laser Microscopy

“…CSLM can be used as a non-invasive tool in the diagnosis of sinonasal inverted papilloma, see Figs. 12.13 and 12.14 [63].…”