Impact of 4K Ultra-High Definition Endoscope in Pituitary Surgery: Analysis of a Comparative Institutional Case Series

Background: Trans-sphenoidal endoscopic surgery has drawn huge benefits from advances in surgical visualization. The Ultra-HD "4K" endoscope has improved 4-fold image resolution compared with HD, but its actual advantages are unclear. Aim of the present study was to assess its usefulness in the early outcome of trans-sphenoidal surgery. Methods: We analyzed a series of 199 trans-sphenoidal pituitary adenoma procedures performed by an experienced team using alternatively HD (n=102) or 4K (n=97) endoscopes. We evaluated extent of resection both subjectively, based on intraoperative surgeon's impression, and objectively based on post-operative MR scan. Results: Baseline patients' characteristics were balanced. Objective near-total and total resection rates were comparable between 4K and HD groups (91.5% vs 86.3% and 64.9% vs 56.9%, respectively). 4K endoscope slightly improved resection rate in recurrent adenoma. At multivariate analysis, the only independent prognosticator of total resection was cavernous sinus invasion. Importantly, 4K endoscope enhanced the reliability of intraoperative judgement on extent of resection, significantly reducing unexpected residuals (12.8% vs 33.3% for HD). Operative features and clinical outcomes were similar. Conclusions: The HD endoscope remains the standard-of-care for pituitary surgery. The 4K enhanced, "immersive" visualization significantly improved the reliability of surgeon's judgment on resection and might be useful in surgically difficult cases.