The modified Whitaker test is a reliable adjunctive rule-out tool for evaluating efficacy after ureteral reimplantation

Background: Ureteral reimplantation (UR) is the standard treatment for distal ureteral stricture, yet postoperative anastomotic restenosis impairs outcomes, with conventional imaging unable to quantify urinary tract obstruction and dysfunction. This study aimed to explore the clinical value of the modified Whitaker test in ruling out upper urinary tract obstruction and assisting postoperative efficacy evaluation after UR.

Methods: A total of 100 patients (105 renal units) who underwent UR from January 2022 to December 2025, with preoperative nephrostomy tube placement and postoperative modified Whitaker test, were prospectively enrolled. Combined standing and supine position examination, gradient perfusion (5~25 mL/min) pressure measurement combined with imaging development classification was used. Patients were classified into three types based on the pyelovesical pressure difference and ureteral peristalsis. Perioperative and follow-up data were collected to evaluate the curative effect.

Results: Among patients undergoing modified Whitaker test after UR, 73 cases (69.52%) were Type I, 24 cases (22.86%) Type II, and 8 cases (7.62%) Type III. The median follow-up time was 12.63 (6.92, 25.80) months. The overall surgical efficacy rate was 92.38% (97/105), and the objective efficacy rate was 98.10% (103/105). In the modified Whitaker test, the median intrapelvic pressure was 20.00 (16.00, 25.50) cmH₂O, the median intravesical pressure was 14.00 (9.50, 20.00) cmH₂O, and the median pressure difference was 5.00 (2.00, 9.00) cmH₂O. The unobstructed results of the modified Whitaker test were consistent with successful overall postoperative efficacy in 85.71% (90/105) of renal units and with successful objective postoperative efficacy in 91.43% (96/105) of renal units. All patients successfully completed the modified Whitaker test without any postoperative discomfort.

Conclusions: UR the modified Whitaker test exhibits excellent negative predictive performance and favorable consistency with mid-term postoperative follow-up outcomes. It serves as a reliable adjunctive tool for ruling out upper urinary tract obstruction and guiding nephrostomy tube removal after UR.