Laser speckle contrast imaging for real-time quantification of colonic perfusion following high versus low tie in anterior rectal resection surgery: a pilot prospective study.

backgroundThe optimal management of the inferior mesenteric artery (IMA) in rectal cancer surgery remains controversial owing to its unclear impact on bowel perfusion. This study aimed to objectively evaluate perfusion differences between high tie (HT) and low tie (LT) using laser speckle contrast imaging (LSCI) and determine its value in guiding surgical decisions.

methodsPatients who underwent laparoscopic anterior rectal resection for rectal or rectosigmoid cancer were prospectively enrolled for either HT or LT. The primary outcome was the maximum perfusion distance (MPD). The secondary outcomes included the Speckle Flow Index (SFI) at the transection site and the frequency of LSCI-guided surgical revisions.

resultsAfter propensity score matching ( n = 30/group), no significant overall difference was found in the median MPD ( P = 0.12) or mean SFI ( P = 0.20) between the HT and LT groups. However, a key finding was the identification of a high-risk HT patient subgroup with critically short MPD, a phenotype that was absent in the LT cohort. Consequently, LSCI guidance prompted surgical revision in 16.7% of the HT patients (vs. 0% in the LT group). Ultimately, this individualized approach resulted in an equally low anastomotic leakage rate (3.3%) in both the cohorts.

conclusionOur results from this pilot study are hypothesis-generating. While the average perfusion did not differ significantly between IMA management techniques, HT posed a unique risk by creating a patient subset with critically compromised perfusion. Real-time LSCI assessment proved effective in identifying these high-risk individuals intraoperatively, prompting timely surgical revisions and thereby reducing the incidence of anastomotic leakage.