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Management of large ureteral stone with severe ureteral tortuosity: A novel technique of “straightening” against the tortuous ureter using simultaneous supine percutaneous nephrolithotomy and retrograde semirigid ureterolithotripsy

DOI: 10.1111/iju.13733 Recently, flexible URS has enabled the treatment of tortuous ureteral stones, but is not available worldwide owing to its high cost, skill dependence and long operative time. Therefore, for hospitals where flexible URS is unavailable, treating large ureteral stones with severe ureteral tortuosity is challenging. Although previously described techniques involve the use of different types of guidewire and ureteric catheters, a severely tortuous ureter can prevent successful retrograde ureteral access in semirigid URSL. Furthermore, forceful attempts at catheterizing ureteral kinks might cause perforation and urinary extravasation. Ureterolithotomy is the available method for treating stones in tortuous ureters, but is more invasive and is associated with greater postoperative morbidity. Therefore, we report our experience and describe a novel method of “straightening” against the tortuous ureter with simultaneous supine PCNL and retrograde semirigid URSL for treating large ureter stones with severe ureteral tortuosity. Between January 2017 and September 2017, eight patients with large ureter stones (>15 mm) and severe ureteral tortuosity who had a failed URSL underwent the modified procedure at Kaohsiung Medical University Hospital, Kaohsiung, Taiwan. All patients received abdominal computed tomography and/or antegrade pyelography to define the stone size and position, and extent of ureteral tortuosity (Fig. 1a). We defined severe ureteral tortuosity as grade 5 vesicoureteric reflux (tortuous ureter with severe dilatation of the ureter and pelvicalyceal system) combined with an S-shaped ureter (tortuous angle of >120°). This study was approved by the Kaohsiung Medical University Hospital institutional review board (ID: KMUHIRB-E(I)-20170273). All patients provided written informed consent. For the operation, the patient was placed in the GMSV position, with the leg ipsilateral to the stone in extension and the other in flexion (Fig. 1b,c). After a PCN tract was created, a hydrophilic guidewire (Radifocus Guidewire M; Terumo, Tokyo, Japan) was antegradely introduced by nephroscopy (Fig. 1d) from the ureteropelvic junction along the ureter to the bladder under fluoroscopic guidance. The distal end of the guidewire was pulled out of the urethra meatus by using forceps under cystoscopy (Fig. 1e). We straightened the guidewire from both ends with tension against the tortuous ureter. After “straightening” the ureter, URS could be used to approach the ureter stones, which were then disintegrated using a holmium:YAG laser. The patients’ demographic data, and intraoperative and postoperative findings are reported in Tables S1 and S2. All patients were treated with ureteral stents without a nephrostomy tube (Fig. 1f). The postoperative stone-free rate at 1-month follow up was 88%, with one patient diagnosed as an upper ureteral stone with multiple tortuous lesions over the ureter not achieving stone-free status; in this case, severe stone impaction led to total ureteral obstruction, which prevented the guidewire from passing through. Finally, the patient was treated with ureterolithotomy. Our novel technique of “straightening” against the tortuous ureter by using the hydrophilic guidewire from both ends of the PCN and urethra under simultaneous supine PCNL and retrograde semirigid URSL represents a significant progress in treating large ureteral stones with severe ureteral tortuosity. The advantages of this approach include the following: (i) achieving a high degree of stone clearance in a single procedure without preoperative ureteral stenting; (ii) conquering the tortuous ureter after “straightening” the ureter and leading to avoidance of ureteral injury, such as ureteral perforation or postoperative ureteral stricture, which are the major complications when treating stones in several ureteral tortuosities using URSL; and (iii) the creation of an open low-pressure system that reduces the absorption of irrigation fluid into the circulation, which is the disturbing and unavoidable problem encountered in URSL. Our method is different from ECIRS, which is the simultaneous contribution of PCNL and flexible URS. To our knowledge, this is the first report of simultaneous supine PCNL and semirigid URSL for treating ureteral stones with severe ureteral tortuosity. The most important part of this modified procedure is the success of passing the guidewire antegradely through the stone and bladder, which is also its limitation in severe stone impaction. Large-