Hello, I'm Matt Ungst and this is Dan Gruber. We're fellows at the Walter Reed Army Medical Center Division of Urogynecology. Today we're going to tell you about a model we've developed for learning advanced cystoscopic procedures including bladder biopsies and double J stent insertion. This model is constructed with equipment that is readily available, two balloons and vinyl tubing. The instrument is used in a regular cystoscopy suite with monitors and instruments that you are familiar with. While there are advanced endoscopic trainers available that utilize computer simulation, our model can be constructed at a fraction of the cost. And because our model is used in the actual cystoscopy suite with the real cystoscope, wires and stents, it can help surgeons improve their coordination with these sometimes awkward procedures. The model consists of a large punch ball party balloon, standard three-eighths inch vinyl tubing and a twelve inch latex balloon. These items are assembled to simulate the right renal collecting system then mounted to three-sixteenths inch foam board. The key to the model is the large party balloon. Party balloons have a long neck that simulates the urethra and this extra appendage that allows it to be connected to the simulated urethra. You may find that any party balloon works, but we found that a large Thomas and Thomas the Tank balloon seems to work best. The first step is to trim the tip off the punch balloon appendage. Don't trim too much or the balloon won't fit snugly to the vinyl tubing and may be prone to leak. Next, attach the balloon, the simulated bladder, to a twenty-six centimeter length of three-eighths inch vinyl tubing. The average female ureter is twenty-six centimeters and using this length will allow your model to work well with the common stent sizes you have available in your hospital. Then attach a second standard twelve inch latex balloon which simulates the right renal pelvis. Secure the balloons to the tubing with small rubber bands or plastic ties. This completes the right renal collecting system. Mount the right collecting system to a three-sixteenths inch foam board. Foam board is available at any craft store and comes in twenty by thirty inch sheets. Cut the sheets in half to make a more convenient size for the mounting. The model works best when the balloons are attached in a somewhat anatomical, ergonomic location on the foam board. Draw a line down the middle of the foam board and mount the simulated collecting system eighteen centimeters from the edge. Then run the plastic tubing in the course of the right ureter and mount the ureteral pelvic junction twenty-four centimeters along the line from the ureter bladder junction. To improve the virtual reality of the model with fluoroscopy, we traced a skeletal outline on the model. Due to trouble locating lead-based paint, we used steel wire to make the traced skeleton visible under fluoro. You can further improve the durability of your model by covering it with latex rubber. Here we are in one of our cystoscopy suites in the urology clinic at Walter Reed to demonstrate the model in action. As you can see, we positioned our necessary equipment as well as the monitors for cystoscopy and fluoro. If the model is to be used with fluoroscopy, body lead should be worn. Cystoscopy tubing and the cystoscope are prepared for standard operative cystoscopy. In order to attain a seal between the cystoscope and the balloon, a rubber band or a tie is placed tightly on the cystoscope sheath. The scope is inserted into the model and the rubber band is moved over the balloon neck. The flexibility of the balloon simulates the usual in and out movement of the cystoscope within the urethra. Training simulation number one, inserting a right double J stent. The key steps for inserting a double J stent are establishing access to the urethra, selecting the correct stent size and placing the stent. For our demonstration, we will use a 26 centimeter 6 French double J stent and a 150 centimeter .035 inch diameter Teflon coated guide wire. Establish access to the urethra directly with the guide wire and advance the wire until resistance is felt. The wire has safely reached the renal pelvis with fluoroscopy. Next, select the correct stent size. You can estimate the appropriate stent length based on the patient's height as shown in this table. Most women between 5 feet 6 and 5 feet 10 will require a 26 centimeter stent. While the surgeon maintains the cystoscope oriented at the ureteral orifice, an assistant loads the stent on the wire followed by the stent pusher. The final step is to insert the stent. Advance the stent with the assistance of the pusher past the 25 centimeter mark. Note that each linear marking on a stent denotes 5 centimeters. When the stent is fully inserted, the final mark, 26 centimeters, will be at the UO. Have your assistant partially retract the wire while you hold counter pressure on the stent with the pusher. Fluoro to confirm the stent has curled in the ureter. Then have your assistant remove the wire while you hold counter pressure on the stent with the pusher. Last, confirm the distal stent curl in the bladder. Training simulation number two, cold cut bladder biopsy. To practice cold cut bladder biopsies with the model, use a new punch ball balloon and insert a strip of foam into the simulated bladder at the location of the previous balloon defect for the ureter. Practice to emphasize with bladder biopsy including grasping pedunculated lesions at the stalk, holding pressure on the stalk to reduce bleeding, and abruptly avulsing the lesion to prevent peeling of the uroepithelium. Training simulation number three, flexible cystoscopy. It is not uncommon for urogynecologists to perform flexible cystoscopy in the clinic without the benefit of a camera and video screen. While this is convenient for the patient, it is more difficult for the surgeon. A drill with a dice inserted into the simulated bladder can be performed with the model to improve the coordination required for this task. That concludes our demonstration of the punch ball advanced cystoscopy trainer. We hope the model gives you an opportunity to improve your urogynecology fellows' exposure and experience with endoscopic procedures such as double J stent placement. All of us at Walter Reed Medical Center, thanks for watching.

advanced cystoscopic procedures

model development

surgeon coordination

renal collecting system simulation

low-cost alternative