Background: For anastomoses in colorectal surgery, in addition to lack of tension and technical precision, good perfusion is an important prerequisite for healing (among many other factors). Tissue perfusion can be quantitatively visualized with hyperspectral imaging. In this paper, the first large case series is presented. Materials and methods: In this prospective, nonrandomized, open-label, single-arm study, hyperspectral imaging was used to define the resection line in relation to oxygenation in left colorectal resections. 102 consecutive patients were included. Before measurement, the surgical resection line was defined and compared with measured border zone. Results: Intraoperative HSI measurement was performed in 102 patients, 7 patients did not show a clear demarcation line. In 95 patients a demarcation line could be shown after cutting the marginal arcade. Demarcation was significantly detectable as early as 1 minute (p<0.001) and continued to significantly decrease up to 3 minutes after arcade transection; however, proximal oxygenation increased. The border zone was not always directly transverse but also oblique. Thus, the planned surgical resection line was within this border zone in 48.2% of cases and distal in 28% of cases. In 4 cases, the HSI showed a previously clinically undetected lesion of the marginal artery, which required a resection. Conclusion: Determination of the resection line by HSI can be performed easily and contact-free without dye. Due to an objectively measurement of tissue oxygen saturation, this method is superior to the clinical assessment by the surgeon.
