CUA 2018: Development and Validation of a 3D-Printed Bladder Model to Simulate Laparoscopic Urethrovesical Anastomosis for Radical Prostatectomy Training

Halifax, Nova Scotia (UroToday.com) The traditionally accepted form of surgical training is direct supervision by an expert, however modern trends in surgery have made this progressively more difficult to achieve. A 3-dimensional (3D) printer makes it possible to convert a patient’s imaging data into accurate models, thus allowing the possibility to reproduce models with pathology and allowing trainees to “practice” surgical skills on these models. Previous studies have demonstrated that surgical trainees need multiple attempts to learn procedures, and the use of these models for surgical-training simulation allows trainees to practice these procedures repetitively in a safe environment until they can master essential steps1. With regards to urologic oncology procedures, the laparoscopic approach of performing a radical prostatectomy is associated with a steep learning curve, especially during the urethrovesical anastomosis. In an attempt to decrease the learning curve for performing a urethrovesical anastomosis, Yanbo Guo, MD, and colleagues developed a 3D printed bladder model for simulated urethrovesical anastomosis training. At the CUA 2018 annual meeting, they presented their experience with the training model, as well as validation results. 

For this study, the final bladder model was produced using a LulzBot® TAZ 6 3D printer ($14 CAD/model). The dimensions mimic the anatomical structures of a human bladder and urethra, and the polymer allows for realistic incising and suture pull-through. During the study time period, urology residents, fellows, and staff completed a laparoscopic training course, which included performing a simulated urethrovesical anastomosis on the 3D model. Laparoscopic video trainers were used with the model affixed inside a simulated patient torso, and each urethrovesical anastomosis was videotaped for construct validation purposes. Following the laparoscopic training course, participants completed an exit questionnaire using five-point Likert scales with six domains.

There were 24 participants, including junior and senior residents, fellows, and staff from seven urology programs which completed the course. The mean age of participants was 29.8 years (±4.6), and the majority were male (n=21). For face validity, participants scored the following on the questionnaire (mean score out of 5): 

  • 3.6 for anatomical realism
  • 3.8 for overall task-based usefulness
  • 4.1 for the urethrovesical anastomosis task itself
  • 4.4 for suturing, knot tying, and cutting. 
For content validity, participants rated overall usefulness as a training tool at 4.3 and improving operative technique at 4.4. Overall reaction scored a mean of 4.2 over the six domains. Finally, a mean of 4.1 was recorded for transferability of skills to the operating room, and a score of 4.3 was indicated for “the model should be incorporated into urology training curricula.” Recently, the model has also been used with the da Vinci robotic console:
bladder model da vinci robot
The strength of the study is the multi-center approach for testing the laparoscopic training model. A possible limitation of the study is that the majority of radical prostatectomies in 2018 are performed either robotically or via an open approach, as such the robotic training model (which is currently underway) may be of more pragmatic use. Dr. Guo and colleagues concluded that this low-cost bladder model has face and content validity for laparoscopic urethrovesical anastomosis training within this study, and skills acquired using the model can prepare urologic trainees for live laparoscopic urethrovesical anastomoses. Furthermore, they note that the videos are currently being evaluated by three expert raters to assess the model’s construct validity.

Presented by: Yanbo Guo, McMaster University, Hamilton, Ontario, Canada
Co-Authors: Jen Hoogenes1, Nathan Wong1, Kevin S Kim1, Bobby Shayegan1, Edward Matsumoto1.
1Department of Surgery, Division of Urology, McMaster University, Hamilton, ON, Canada

References:
1. Waran V, Narayanan V, Karuppiah R, et al. Injecting realism in surgical training- initial simulation experience with custom 3D models. J Surg Educ. 2014;71(2):193-197.


Written By: Zachary Klaassen, MD, Urologic Oncology Fellow, University of Toronto, Princess Margaret Cancer Centre Twitter: @zklaassen_md at the 73rd Canadian Urological Association Annual Meeting - June 23 - 26, 2018 - Halifax, Nova Scotia