Imaging peritoneal blood vessels through optical coherence tomography angiography for laparoscopic surgery.

Laparoscopic surgery presents challenges in identifying blood vessels due to lack of tactile feedback. The Image-Guided Laparoscopic Surgical Tool (IGLaST) integrated with Optical Coherence Tomography (OCT) has potential for in-vivo blood vessel imaging, however distinguishing vessels from surrounding tissue remains a challenge. In this study, we propose utilizing an inter-A-line intensity differentiation-based OCT angiography (OCTA) to improve visualization of blood vessels. By evaluating a tissue phantom with varying flow speeds, we optimized the system's blood flow imaging capabilities in terms of minimum detectable flow and contrast-to-noise ratio. In-vivo experiments on rat and porcine models, successfully visualized previously unidentified blood vessels and concealed blood flows beneath the 1mm depth peritoneum. Qualitative comparison of various OCTA algorithms indicated that the intensity differentiation-based algorithm performed best for our application. We believe that implementing IGLaST with OCTA can enhance surgical outcomes and reduce procedure time in laparoscopic surgeries. This article is protected by copyright. All rights reserved.