Jae-Jun Kim, PhD1, Alex Watras1, Hewei Liu, PhD1, Zhanpeng Zeng1, Jacob A Greenberg, MD2, Charles P Heise, MD2, Yu Hen Hu, PhD1, Hongrui Jiang, PhD1. 1University of Wisconsin-Madison, 2University of Wisconsin School of Medicine And Public Health
Introduction: Current laparoscopic imaging systems require frequent and sometimes cumbersome manual adjustment of the camera to facilitate minimally invasive surgery. The field of view of a single camera is restricted, and inadequate view orientation may hinder the procedural efficiency. An advanced laparoscopic imaging system is presented here that promises enlarged field of view (FoV) and improved procedural efficiency.
Methods: This advanced laparoscopic imaging system consists of a trocar with five miniaturized cameras connected via a real-time video stitching program. To test our imaging system, we developed a modified bean drop task that consists of one saucer with beans and four inverted cups placed in four different positions (Figure (a)). Each bean is grasped from the saucer and transferred to the inverted cups where it must be dropped through a small caliber hole. We performed the modified bean drop task in a commercial simulator box to demonstrate the enlarged FoV of this advanced laparoscopic imaging system. The video stitching program receives video streams from five individual cameras and stitches the view of these five videos in real time to provide a single video stream with enlarged FoV. A projective transformation was calculated using matched feature points to combine each image (frame) from different cameras into a single image (frame) of the stitched video. One of the five cameras placed at the center part of the camera array provides the main view. The other four cameras supplement the additional views surrounding the main view to extend the overall FoV.
Results: The specially designed trocar can easily deploy and retrieve the miniaturized cameras. Hence the inner side of the trocar is not occupied by the cameras during operation and can still be utilized by an instrument. Therefore, our system can potentially reduce the number of ports required for a given procedure. To demonstrate the advantage of our laparoscopic imaging system, we performed the modified bean drop task in a simulator box using our laparoscopic imaging system. The figures below show that beans were picked up with a grasper and dropped into the holes of inverted cups aided by the real-time stitched video without any physical camera maneuver or secondary assistant. The red dotted circles are traces of moving beans. The stitched video can track the complete motion of the bean without any camera movement (Figure (b)-(f)). In contrast, images g and h show that a single camera alone cannot track the whole trajectory of the beans, nor cover the saucer and the inverted cups simultaneously.
Conclusions: We successfully demonstrate a novel laparoscopic imaging system that provides large FoV and improves efficiency and range of operation. This system frees up a surgical port and potentially eliminates the need for physical maneuvering of the laparoscopic camera by an assistant. Further development of this imaging system hopes to offer an alternative means for high performance visualization during laparoscopic surgery.
Presented at the SAGES 2017 Annual Meeting in Houston, TX.
Abstract ID: 91192
Program Number: ET005
Presentation Session: Emerging Technology Session (Non CME)
Presentation Type: Podium