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Updated: Feb 16, 2026

Intraoperative Ultrasound in Spinal Surgery
Published on: August 17, 2022
Ultrasound for Intraoperative Confirmation of Antegrade Ureteral Stent Placement During Laparoscopic Pyeloplasty
David B Bayne1, Manint Usawachintachit1, Thomas Chi1
1Department of Urology, University of California, San Francisco, CA.
Objective:
To describe our ultrasound technique for confirming intraoperative, antegrade-placed ureteral stent position during laparoscopic pyeloplasty.
Background:
Disadvantages of retrograde stent placement include the need to reposition the patient into and out of the lithotomy position. Antegrade stent placement can reduce procedure time but requires confirming appropriate distal placement into the bladder with cystoscopy, percutaneous drain placement, or instillation of methylthioninium chloride or indigo carmine.
Materials And Methods:
A 3-way 20-French Foley catheter is placed after induction with general anesthesia. Laparoscopic transperitoneal dismembered pyeloplasty is performed. Intraoperatively, the bladder is filled retrograde with 300ccs normal saline. After completing the posterior suture line of the ureteral anastomosis, a 4.8-French, 26-cm ureteral stent is placed antegrade down the ureter using a 5-French exchange catheter and guidewire. The stent is passed over the guidewire into the bladder. The proximal curl is then placed into the renal pelvis and the anastomosis is completed. Without patient repositioning, an intraoperative bladder ultrasound is performed to identify the distal stent curl within the bladder lumen.
Results:
This technique demonstrated that ultrasound can guide antegrade stent placement in adult, laparoscopic ureteral surgery. It eliminated the need for intraoperative repositioning of the patient for intraoperative cystoscopy to confirm stent placement and was performed successfully during 8 laparoscopic pyeloplasty cases without failure. Ultrasound is likely more sensitive compared with looking for the presence of vesicoureteral reflux after stent placement, prevents stent malposition, and avoids the use of intravesical dyes that upon reflux can stain tissues and obscure surgical planes.
Conclusion:
Here we demonstrate successful use of intraoperative ultrasound to confirm appropriate distal stent positioning in the bladder of an adult patient following antegrade stent placement for laparoscopic dismembered pyeloplasty. To our knowledge, this has been described in pediatrics, but never in adult patients.
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