Kyle R Miller, MD, MBA1, Shetha Shukair, PhD2, Amal Chaturvedi, PhD2, Paul LeRolland, MS2, David Mahvi, MD1, Jonathan Gunn, JD, PhD2. 1Northwestern University Feinberg School of Medicine, 2Briteseed, LLC
Introduction: Minimally invasive procedures have improved surgical outcomes and allowed for the treatment of some of the most complex and advanced pathologies with shorter recovery time. As surgeons adopt more minimally invasive techniques, visual and haptic acuity decreases, requiring new methods to map the vasculature, as well as ureters and bile ducts, in order to strategically cut or avoid critical structures. The aim of this preclinical study was to demonstrate the ability of a novel optical system to detect vasculature, without the use of a contrast agent, as well as ureters after intravenous injection of methylene blue.
Methods and Procedures: A grasper equipped with a dual-wavelength LED array on one jaw and a sensor array on the other jaw was used to interrogate tissues within the abdominal and pelvic areas of six female porcine subjects. Characterization of the arteries and other vital structures (i.e. ureters, bile ducts) was performed in real time after laparotomy on the anesthetized animals using a custom graphic user interface in MATLAB to collect, process and display the data received by the sensor array.
Results: Our optics-based system was able to detect and track in real time all of the tested vessels in living porcine subjects. In addition, vessel sizes were estimated by the system to within a millimeter of error when compared to gross anatomical measurements. Furthermore, characterization was accomplished when vessels were in a native state, completely covered by surrounding tissues. Our results confirm the feasibility of identifying and visualizing vasculature and ureters between the jaws of a surgical instrumentation in real time (~0.3 seconds) without the need for expensive or complex imaging systems.
Conclusions: This technology provides surgeons with a dynamic, colorized map of 2-8mm blood vessels between the instrument jaws, as well as methylene blue-stained ureters and bile ducts. The real time data also included size estimation, wtith sub-millimeter accuracy, of the blood vessels found in the abdominal and pelvic region. Real-time detection of arteries and ureters provides surgeons with added information to safely assess the risk profile of a procedural maneuver. Integration of optical sensor systems into existing surgical tools would minimize the learning curve normally experienced when using new surgical technologies and preserve the surgical workflow.