'Boxing in the corner': A modified retrograde approach for the management of proximal ureteric stones of 1-2 cm.

Objectives

To study a modification to the conventional retrograde ureteroscopic approach for treating proximal ureteric stones of 1-2 cm; we intentionally push the stone from the proximal ureter into a favourable calyx then the flexible ureteroscope is used to fragment the trapped stone using laser lithotripsy ('boxing in the corner'). Patients and methods: The study was conducted in a randomised prospective manner and included 100 patients who presented with a single proximal ureteric stone of 1-2 cm. We randomised the patients into two equal groups: Group A (50 patients) underwent the conventional retrograde technique (CRT) and Group B (50 patients) underwent the modified retrograde technique (MRT) with the primary intention of relocating the stone into a favourable calyx. Intended relocation of the proximal ureteric stone in the MRT group was achieved in a stepwise manner. All intraoperative parameters and postoperative outcomes were recorded and compared between the two groups.

Results

There was no statistical significant difference in terms of the patients' demographics and stone criteria between the two groups. The stone-free rate (SFR) was significantly higher in Group B (92%) compared to Group A (78%) (P = 0.049). Fluoroscopy time was significantly longer in Group B (P < 0.001), while operative time, lithotripsy time and hospital stay were comparable. There was no difference between the groups regarding complications.

Conclusion

The MRT was found to be safe and more effective than the CRT for treating proximal ureteric stones of 1-2 cm, with a significantly higher SFR. Abbreviations CONSORT: Consolidated Standards of Reporting Trials; ESWL: extracorporeal shockwave lithotripsy; fURS: flexible ureteroscope; NCCT: non-contrast CT; SFR: stone-free rate; YAG: yttrium-aluminium-garnet.