IntroductionAnderson-Hynes (A-H) dismembered pyeloplasty has remained nearly unchanged since its introduction in 1949. The authors present a modification of the uretero-pelvic anastomosis as described by Anderson and Hynes. The new approach, called the W-type suture, is thought to be more watertight and associated with fewer complications than the original.AimTo assess the effectiveness of the modification of Anderson-Hynes dismembered pyeloplasty named the W-type suture.Material and methodsThe research is a retrospective study of 99 patients who underwent laparoscopic A-H pyeloplasty. In 49 patients unmodified laparoscopic A-H pyeloplasty was carried out. Fifty patients underwent laparoscopic A-H pyeloplasty with the anastomosis made using the aforementioned W-type suture. To assess the effectiveness of the W-type suture, we compared urine leakage duration – a direct indicator of anastomosis tightness – and frequency of postoperative complications.ResultsThe mean duration of urinary leakage was 3 ±1.16 days for the W-type suture anastomosis group and 3.57 ±1.14 days for the unmodified A-H pyeloplasty group (p < 0.05). The frequency of post-operative complications did not statistically significantly differ between the groups except for fever (18.4% vs. 4%; p < 0.05).ConclusionsThe analysis of the collected data showed that the W-type suture might be a promising alternative to a traditional approach of performing the ureteropelvic anastomosis. Further research should be done to minimize biases present in this study, which might have influenced our results.