RIRS for Treatment of Stones in Congenital Anomalous Kidneys

Retrograde Intrarenal Surgery for Treatment of Stones in Congenital Anomalous Kidneys: Case Matched Comparative Study With Extracorporeal Shockwave Lithotripsy

The anatomic renal abnormalities like altered spatial relations with adjacent organs, abnormal calyceal orientation, and anomalous vascular patterns make the active treatment of stones in the congenitally malformed kidney a great challenge for urologists. In this prospective study, the investigators will evaluate the outcome of retrograde intrarenal surgery (RIRS) with extracorporeal shockwave lithotripsy (SWL) for the treatment of stones in the kidneys with rotation or position anomalies.

In current stone guidelines, the recommendations for stone therapy in the kidneys with normal anatomy are clearly stated; however, there is also no clear suggestion and treatment modality in regards to the stone treatment in anomalous kidneys. Nowadays, open surgery, percutaneous nephrolithotomy (PNL), SWL, and RIRS are used for the treatment of these kidney stones. However, there is no clear consensus on which treatment modalities should be used; each modality has its unique advantages and drawbacks. in this study, the investigators will prospectively evaluate the safety and efficacy of RIRS in treatment of stones in kidneys with rotation or position anomalies. The investigators will compare the results with a matched group of patients who were treated with SWL. The results of this study may help clarify treatment options in the management of patients with stones and renal anomalies.

The standard RIRS will be performed using a disposable flexible ureteroscope. Holmium: YAG laser will be used for stone dusting and fragmentation. If indicated, JJ ureteral stent will be placed at the end of the procedure.

The medical records of all patients who underwent SWL at our institution in the past five years will be reviewed. Patients with renal rotation or position anomalies, as defined by NCCT and/or IVU, will be included for possible study participation.

The standard RIRS will be performed using a disposable flexible ureteroscope. Holmium: YAG laser will be used for stone dusting and fragmentation. If indicated, JJ ureteral stent will be placed at the end of the procedure.

Patients who underwent SWL at our institution in the past five years. According to (a) the type of renal anomaly (rotation, position, or rotation/position anomaly), (b) the size of the stone (±5 mm), (c) location of the stone (lower polar or non-lower polar), and (d) density of the stone (>800 HU or ≤800 HU), matched cases will be selected for comparison.

Inclusion Criteria: The study will include patients with renal stones up to 20 mm in size in a kidney with rotation or position anomalies. Exclusion Criteria: Pregnant women. Uncorrectable coagulation disorders. Urinary tract obstruction distal to the stone. Active infection. Stone in a calyceal diverticulum