Intraoperative Autofluoreszenz-Bildgbung von Hypophysenadenomen mittles konfokaler Laser-Endomikroskopie: Eine Proof-of-Concept-Studie

Pituitary adenomas are common intracranial tumors requiring precise surgical resection to minimize complications and optimize patient outcomes. Intraoperative visualization remains challenging due to the lack of real-time cellular-level imaging. This study aimed to evaluate the feasibility of using label-free confocal laser endomicroscopy (CLE) as a tool for identifying and delineating pituitary adenoma tissue intraoperatively.

The pilot study was conducted on patients undergoing microscopical and endoscope-assisted transsphenoidal surgery for pituitary adenoma resection (n=5) using a clinical CLE device (Convivo, Zeiss). CLE was performed solely ex vivo (n=2), intraoperatively (n=1), or intraoperatively with subsequent ex vivo analysis of the resected tissue samples (n=2). Importantly, CLE was performed without contrast agent leveraging its ability to detect autofluorescence signals from endogenous fluorophores. Representative (n=5) label-free CLE images (267 × 475 μm) of each case were selected and analyzed for signal intensity, size and density of autofluorescence signals.

CLE provided autofluorescence images of pituitary adenoma tissue in all cases and surgeons reported confidence in handling the endoscopic probe during intraoperative imaging. Ex vivo and in situ imaging revealed consistent autofluorescence patterns, but in situ imaging was severely affected by motion artifacts resulting from acquisition times of ~1 s/image (CLE system default). Pituitary adenoma were predominantly characterized by dense punctuate autofluorescence. Typically >200 structures / image with diameter of 3.4±0.4 µm (mean±SD) were observed. Larger autofluorescent objects with a diameter 11.8±4.4 µm were detected less frequently (usually 5-10 / image) and were identified as cells by comparison to histopathology. Fiber-like structures were noteded in 3/5 cases.

This study demonstrates CLE for autofluorescence imaging as a potential intraoperative tool for pituitary adenoma visualization. It holds promise for high-resolution insights into tumor microstructure with the potential to enhance surgical precision and reduce residual tumor. Further research with larger cohorts is warranted to validate these findings and refine this novel imaging approach.