Medical Student Research Fellowship for Summer 2010
Mentor: Daniel J. Scott, MD, FACS
Room number: E7.116
Mail Code: 9156
Phone number: 214-648-2677
Project title: Camera Comparison Trial
Human subjects IRB approved project number (where applicable): N/A
Animal subjects IRB approved project number (where applicable): APN 2009-0138
Project Type (patient-based research, animal-based research, or basic research; this characterization is only to permit a general classification for grouping similar types of projects):
Brief Description of Project:
The goal of the project is to evaluate the MAGS Camera (expected SRM version
in collaboration with Storz) compared to a conventional laparoscope and flexible
endoscope in tests conducted on bench (optical characteristics), box-trainer
(surgeon performance on FLS suturing task), and live porcine (surgeon performance
during in-vivo suturing, 1 animal with multiple surgeons) models. Both conventional
multiport and SSL testing configurations will be used, with the aim of showing
clear superiority of the MAGS camera in objectively improving surgeon performance
We previously conducted a comparative trial between the MAGS camera ("India Cam" version), a laparoscope, a flexible endoscope, and a PillCam in these same 3 environments (bench, box, and pig). We found that the MagCam and the flexible endoscope had clinically acceptable performance but we found that results of surgeon performance with these systems were inferior compared to a 10mm laparoscope.
With the collaborative work being done in conjunction with Storz, we expect that the new version of the MAGS camera will have superior performance compared to our prior India Cam version. Thus, we are eager to objectively measure the performance of the new MAGS camera in a similar comparative trial. Also, in our previous study, we did not perform test in a SSL environment. Given the obvious utility of the MAGS camera of decreasing instrument conflicts in an SSL environment, this added study component should yield impressive results.
Preliminary meetings indicated a planned design freeze on the new MAGS camera prototype in May 2010. Thus, we plan to initiate this study in June.
The first test environment will be objective bench evaluations of optical characteristics of all 3 camera systems (MAG Cam, Laparoscope (10mm Storz), and Flexible Endoscope (Olympus GIF 160 or Storz if available). Tests will include resolution at standardized distances, color quality evaluation, field of view, and depth of focus.
The second environment will be a box trainer modified to be compatible with the MAGS system. The FLS suturing task for laparoscopic suturing with intracorporeal knot-tying will be used. Each camera system will be used in a randomized fashion as 4 expert surgeons perform 10 consecutive repetitions of the task, generating 40 data points for each of the 3 cameras. Performance will be measured using standard FLS metrics, including completion time and errors, which have been extensively validated. The first round of test will be performed using a standard multi-port approach. The tests will then be repeated using a SSL set-up. For both sets of tests, internal and external views (blinded to surgeon identity for possible post-hoc analysis) will be video captured and data regarding instrument conflicts will be documented. Surgeons will also complete a NASA TLX Workload evaluation instrument and a survey regarding task difficulty after each repetition.
The third environment will be a live porcine model (non-survival) that we have used previously for similar purposes and have published in several papers. A mock Nissen fundoplication will be created by dissecting the upper stomach and pulling the fundus through the retroesophageal window. This portion of fundus will be sutured to the right crus such that the tissue may not dislodge from the appropriate location. 3 pairs of marking sutures will be placed on the left and right portions of the fundus as targets for laparoscopic suture placement. The task will include the surgeon placing 3 simple interrupted sutures laparoscopically at the pre-marked locations and tying them intracorporeally. Surgeon performance will be measured in-vivo and separately for each suture using the same standardized FLS metrics, including completion time and errors (knot slippage, tissue gap, or placement inaccuracy in mm from targets). Each camera system will be used in a randomized fashion as 4 expert surgeons perform 3 consecutive repetitions of the task (9 sutures per surgeon), generating 36 data points for each of the 3 cameras. The first round of test will be performed using a standard multi-port approach. The tests will then be repeated using a SSL set-up. For both sets of tests, internal and external views (blinded to surgeon identity for possible post-hoc analysis) will be video captured and data regarding instrument conflicts will be documented. Surgeons will also complete a NASA TLX Workload evaluation instrument and a survey regarding task difficulty after each repetition.
It is our hope and expectation that we will again see inferiority of the flexible endoscope compared to a laparoscope, but that the new MAGS camera will have equal performance to the laparoscope. Thus, we aim to generate objective data supporting the image quality of the new MAGS camera. We also aim to generate objective data supporting the benefit (in terms of decreased instrument conflicts, improved ergonomics, and superior surgeon performance) of the MAGS camera in the SSL environment.
Victoria will attend our regularly scheduled research team meetings, assist with performance of the operations and experiments, assist with collection of data (written data sheets and video capture), assist with analysis of data, assist with assessment of instrumentation short comings, and assist with ongoing collective efforts to generate ideas for instrumentation improvements. The above project is expected to result in publications; Victoria will be authored on these for her research contributions.
Previous Research Activities or Publications with Medical Students:
" Medical Student Summer Research Externs, UT Southwestern Medical Center,
Brian Miller, June - August 1998
William Young, June - August 1999
Rishi Taneja, June - August 2000
Philip Ho, June - August 2008
" Medical Student Research Intern, Southwestern Center for Minimally Invasive Surgery, UT Southwestern Medical Center, Dallas, TX
Thomas Sims, July 2001 - June 2002
Alykhan Nagji, January - March 2006
" Medical Student Research Externs, Tulane Center for Minimally Invasive Surgery, Tulane University School of Medicine, New Orleans, LA
Sarah Markley, July - August 2004
John Odero, July - September 2003
Daniel Hayes, June 2003, January 2004
" Postdoctoral Research Fellow, Tulane Center for Minimally Invasive Surgery, Tulane University School of Medicine, New Orleans, LA
Rafael Sierra, MD October 2002 - June 2005 (Matriculated into Surgery Residency July 2005)
" Postdoctoral Research Fellow, Southwestern Center for Minimally Invasive Surgery, UT Southwestern Medical Center, Dallas, TX
Antonio Castellvi, MD, July 2008 - June 2009 (Matriculation into Surgery Residency July 2009)
UTSW Summer 2008: Philip Ho
1. Castellvi AO, Tang SJ, Hogg DC, Ho PW, Hollett LA, Olukoga CO, Cadeddu JA, Scott DJ. Completely Transvaginal NOTES Using Novel Endoscopic Instrumentation Cholecystectomy in a Porcine Model. Surg Endosc (abstract, in press; manuscript in preparation).
2. Castellvi AO, Tang SJ, Bergs R, Hogg DC, Ho PW, Hollett LA, Fernadez R, Cadeddu JA, Scott DJ. Hybrid Transvaginal NOTES Sleeve Gastrectomy in a Porcine Model Using a Magnetically Anchored Camera and Novel Instrumentation. Surg Endosc (abstract, in press; manuscript in preparation).
(Additional citations for other students is available if needed)