To improve the reliability of our results, we employed a propensity score matching method to pair every SISU case with a BMU case that had the closest preoperative characteristics. Using survival analysis and predicted failure rates, we provided readers with clear and sound conclusions, making this study one of the most impactful regarding SIS use for bulbar urethroplasty.
While the main purpose of this study is obvious -to compare SISU and BMU-we incidentally found an unexpected yet interesting correlation. In our centre, all patients undergo several uroflowmetry tests after catheter removal following urethroplasty. The first uroflowmetry is performed within 2 months after the surgery; thus, we define the patients’ baseline Qmax and compare it with the results during follow-up. In the multivariable Cox regression, the first Qmax result was a significant predictor of failure, which is something that was never discovered before. All previous studies on uroflowmetry after urethroplasty focus on the Qmax value at the time when the recurrence is diagnosed, or on the postoperative Qmax change compared to the preoperative values. We found that also the absolute value of the first postoperative Qmax, just after the stricture has been treated, is also a predictor of failure. If this finding is confirmed by future studies, reconstructive surgeons would have an easy-to-access and readily available investigation to tailor follow-up after the surgery.
We believe that our study widens the armamentarium of the reconstructive urologist, giving a more solid indication of the use of SIS for bulbar urethroplasty. Firstly, we showed that at 13 years outcomes are acceptable (68%), although worse than BM (83.4%). Secondly, we provided some clinical factors that can be used to select the most appropriate patients for SISU. More specifically, a history of internal urethrotomy and long strictures are both predictors of failure and in these cases, a BMU should be preferred. Regarding stricture length, we built the predicted success rates from the multivariable Cox regression model and depicted that strictures longer than 3cm have predicted success rates lower than 80%, which are far from the predictions for BMU. This means that for strictures longer than 3cm, the difference between BM and SIS seems to become remarkable and a BMU is advocated.
We encourage future research to include the assessment of the uroflowmetry Qmax performed within 2 months after the urethroplasty to further investigate the role of this exam. Also, we support the use of SIS for bulbar urethroplasty for patients where it is not possible to use BM, with short strictures, and without a history of internal urethrotomy.
Written by: Enzo Palminteri,1 Stefano Toso,2 Mirko Preto,3 Lorenzo Gatti,4 Omid Sedigh,5,6 Nicolò Maria Buffi,6,7 Giovanni Ferrari,4 Andrea Gobbo6,7
- Center for Urethral and Genitalia Reconstructive Surgery, Humanitas Cellini, Turin, Italy
- Department of Urology, University of Modena and Reggio Emilia, Modena, Italy
- Urology Clinic-A.O.U. "Città della Salute e della Scienza"-Molinette Hospital, University of Turin, Turin, Italy
- CURE Group, Department of Urology, Hesperia Hospital, Modena, Italy
- Department of Urology and Reconstructive Andrology, Humanitas Gradenigo, Turin, Italy
- Department of Biomedical Sciences, Humanitas University, Milan, Italy
- Department of Urology, IRCCS Humanitas Research Hospital, Rozzano, Milan, Italy
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