Shetha A Shukair, PhD1, Amal Chaturvedi, PhD1, Paul A LeRolland, MS1, Kyle R Miller, MD, MBA2, Mayank Vijayvergia, MS1, Hariharan Subramanian, PhD1, Jonathan W Gunn1. 1Briteseed, LLC, 2Northwestern University Feinberg School of Medicine
Objective: 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 our novel optical technology is to detect vasculature, without the use of a contrast agent, as well as to detect ureters and bile ducts after intravenous injection of methylene blue.
Methods and Device Description: A grasper equipped with a dual-wavelength LED array on one jaw and a sensor array on the other jaw was developed and validated using ex vivo porcine tissues. Additionally, the prototype was used to interrogate tissues within the abdominal and pelvic areas of live 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.
Preliminary 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/Future Directions: This technology provides surgeons with a dynamic, colorized map of native blood vessels, as well as methylene blue-stained ureters and bile ducts, between the instrument jaws. The real time data also includes size estimation, with 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. The next step will be to miniaturize the technology and integrate it into the most useful surgical tools (i.e. Maryland dissectors, vessel sealers, etc.). Integration of optical sensor systems into existing surgical tools minimizes the learning curve normally experienced when using new technologies and preserves the surgical workflow.