Background Utility and usability of laser speckle contrast imaging (LSCI) in detecting real-time tissue perfusion in robot-assisted surgery (RAS) and laparoscopic surgery are not known. LSCI displays a color heatmap of real-time tissue blood flow by capturing the interference of coherent laser light on red blood cells. LSCI has advantages in perfusion visualization over indocyanine green imaging (ICG) including repeat use on demand, no need for dye, and no latency between injection and display. Herein, we report the first-in-human clinical comparison of a novel device combining proprietary LSCI processing and ICG for real-time perfusion assessment during RAS and laparoscopic surgeries. Methods ActivSight™ imaging module is integrated between a standard laparoscopic camera and scope, capable of detecting tissue blood flow via LSCI and ICG in laparoscopic surgery. From November 2020 to July 2021, we studied its use during elective robotic-assisted and laparoscopic cholecystectomies, colorectal, and bariatric surgeries (NCT# 04633512). For RAS, an ancillary laparoscope with ActivSight imaging module was used for LSCI/ICG visualization. We determined safety, usability, and utility of LSCI in RAS vs. laparoscopic surgery using end-user/surgeon human factor testing (Likert scale 1–5) and compared results with two-tailed t tests. Results 67 patients were included in the study—40 (60%) RAS vs. 27 (40%) laparoscopic surgeries. Patient demographics were similar in both groups. No adverse events to patients and surgeons were observed in both laparoscopic and RAS groups. Use of an ancillary laparoscopic system for LSCI/ICG visualization had minimal impact on usability in RAS as evidenced by surgeon ratings of device usability (set-up 4.2/5 and form-factor 3.8/5). LSCI ability to detect perfusion (97.5% in RAS vs 100% in laparoscopic cases) was comparable in both RAS and laparoscopic cases. Conclusions LSCI demonstrates comparable utility and usability in detecting real-time tissue perfusion/blood flow in RAS and laparoscopic surgery. Graphical abstract

Purpose: Real time intraoperative perfusion assessment may reduce anastomotic leaks. Laser Speckle Contrast Imaging (LSCI) provides dye-free visualization of perfusion by capturing coherent laser light scatter from red blood cells, and displays perfusion as a colormap. Herein, we report a novel method to precisely quantify intestinal perfusion using LSCI.Methods: ActivSight TM is a FDA-cleared multi-modal visualization system that can detect and display perfusion via both Indocyanine Green imaging (ICG) and LSCI in minimally invasive surgery. An experimental prototype LSCI perfusion quanti cation algorithm was evaluated in porcine models .Porcine small bowel was selectively devascularized to create regions of perfused/watershed/ischemic bowel and progressive aortic in ow/portal vein out ow clamping was performed to study arterial vs. venous ischemia. Continuous arterial pressure was monitored via femoral line.Results: LSCI perfusion colormaps and quanti cation distinguished between perfused, watershed, and ischemic bowel in all vascular control settings: no vascular occlusion (p = 1.52 x 10 -15 ), aortic occlusion (p = 9.58 x 10 -13 ), and portal venous occlusion (p = .00193). LSCI quanti ed similar levels of ischemia induced by states of arterial in ow and venous out ow occlusion. LSCI-quanti ed perfusion values correlated positively with higher mean arterial pressure and with increasing distance from ischemic bowel.Conclusion: LSCI relative perfusion quanti cation may provide more objective real-time assessment of intestinal perfusion, by quantifying currently subjective gradients of bowel ischemia and recognizing both arterial/venous etiologies of ischemia.