The Development and Testing of a Tethered, Independent Camera for NOTES and Single-site Laparoscopic Procedures

Background:
“Tunnel vision” associated with flexible endoscopes used in NOTES and rigid laparoscopes used in Single Site Laparoscopic (SSL) procedures can present the surgeon with a disorienting view of familiar surroundings. Because the working tools are in-line with the view in these approaches, it is also difficult to achieve adequate instrument triangulation, a critical component of successful surgical technique. A more familiar – and potentially more useful – vantage point would be from above, looking down at the surgical field, i.e. a “Stadium View”.
Objective:
Develop mobile “stadium-view” camera prototypes that are deployable, operable and retrievable using NOTES techniques.
Materials and Methods:
Cylindrical (15mm diameter, 29 mm length) prototypes were built using white light LEDs for illumination and a near-VGA (640×480) resolution CMOS camera. The prototypes were delivered to the abdominal cavity through an overtube (Steerable Flex Trocar, Ethicon Endo-Surgery, Cincinnati, Ohio); the electronic tether for power and video signal was pulled through the abdominal wall using a 2mm rigid grasper. The prototype was attracted to the abdominal wall magnetically. Surgeons and a gastroenterologist performed the procedures in IACUC-approved porcine labs with assistance from an Olympus two-channel gastroscope. Video was acquired by both the gastroscope and the prototype camera.
Preliminary Results:
Introduction of the device through the Steerable Flex Trocar into the peritoneal cavity, as well as magnetic coupling to the abdominal wall, was straightforward. Illumination was adequate to provide reasonable imagery of nearby abdominal organs. Bowel was successfully sutured laparoscopically under visualization provided by the prototype. The tether was only slightly limiting to device mobility. For example, with rigid trocars in place to acquire lap video, while magnetically manipulating the camera for a different view, the tether would hang up on the lap trocar tip and cause the camera to be released from the external magnetic attraction. Reacquiring the camera magnetically, however, was trivial. All points on the abdominal wall could be reached via the magnetic control, and the camera could be successfully aimed through abdominal palpation. Retrieval of the camera through the Steerable Flex Trocar was uncomplicated.
Conclusions/Expectations:
The prototype camera provides the NOTES surgeon a point of view similar to that of a laparoscope, but would leave virtually no abdominal scar. The image quality is not currently as good as commercial laparoscopes or endoscopes, but this issue will be resolved as CMOS technology improves. The stadium view helps to overcome limitations associated with in-line visualization and working tools. Use of such a camera in NOTES or SSL could enable reduction of the number/size of ancillary trocars, reduce the size of the SSL port, and/or increase the number of working devices that can be deployed through a scope or port.


Session: Podium Presentation

Program Number: S062

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