TRIDENT: inTRaoperative Imaging DEvice based on endogeNous opTical properties to evaluate bowel oxygenation in left-sided colorectal resections. Observational first-in-human pilot safety trial.

Abstract

Background: Adequate tissue oxygenation at the anastomotic site is a key determinant of healing after colorectal surgery. Current intraoperative imaging technologies aimed at assessing bowel perfusion present several limitations, including the need for exogenous contrast agents, limited quantification capabilities, or suboptimal integration within the surgical workflow. Single Snapshot Imaging of Optical Properties (SSOP) is a contrast-free optical imaging technology capable of quantifying tissue oxygen saturation (StO₂) in real time. This first-in-human observational study aimed to evaluate the intraoperative safety and technical feasibility of SSOP imaging using the Trident system during left-sided colorectal resections.

Methods: In this prospective, single-center feasibility trial, patients undergoing elective left-sided colorectal resection with primary anastomosis were enrolled. After bowel exteriorization, surgeons identified the intended proximal transection line based on their clinical judgement. SSOP imaging was then performed to quantify tissue oxygenation along the exposed colon segment before resection. The primary endpoints of the study were assessing the overall intraoperative safety and workflow feasibility of the Trident system. The secondary endpoint was to obtain wide-field oxygen saturation (StO₂) status images of exteriorized human colon and studying the relationship between oxygen saturation images and a priori surgeon-determined transection lines.

Results: Between September 2023 and April 2024, 10 patients were enrolled (8 males; mean age 65.5 ± 11.8 years; mean BMI 27.5 ± 4.6 kg/m²). SSOP imaging was successfully completed in 9 patients. The mean time required for device positioning and image acquisition was 4.45 ± 0.53 min. Surgeons rated the overall workflow as excellent or good in 100% of cases and no sterility breaches occurred. Quantitative SSOP analysis demonstrated that a priori surgeon-defined transection lines coincided with regions presenting maximal oxygenation in one of the nine cases; in all other cases, transection lines were located well within perfused tissue or proximal to oxygenation transition zones identified by SSOP. No anastomotic leaks were observed.

Conclusions: This first-in-human study demonstrated that SSOP imaging using Trident is safe, feasible, and compatible with standard surgical workflow during left-sided colorectal resections. The ability to provide real-time, quantitative, contrast-free mapping of bowel oxygenation may represent a promising tool for intraoperative perfusion assessment. Larger prospective studies are needed to evaluate whether SSOP-guided surgery can improve anastomotic outcomes (NCT05973227).