Prevention of stone retropulsion during ureteroscopy: Limitations in resources invites revival of old techniques

OBJECTIVE: To compare a modified technique using the Dormia basket vs Stone Cone for stone entrapment to avoid proximal stone migration during ureteroscopic pneumatic lithotripsy of ureteric stones. PATIENTS AND METHODS: Our study included all patients with ureteric stones of <15 mm who underwent ureteroscopic pneumatic lithotripsy from January 2015 to September 2018. The study had two arms that were conducted over two consecutive periods; the first included 72 patients in whom we used the Stone Cone (Group 1) and the second included 86 patients in whom we started to use a Dormia basket with a modification (Group 2) to guard against proximal stone migration. RESULTS: Both groups were comparable for gender, age, and stone characteristics. Lower ureteric stones were the most prevalent as they represented 62.5% and 60.5% in groups 1 and 2, respectively; while upper ureteric stones were respectively found in 16.7% and 17.4%. Chemical stone analysis revealed that calcium oxalate stones were most predominant accounting for 51.3% and 51.1% in groups 1 and 2, respectively. Most of the stones were radio-opaque stones representing 57% and 58.1% in groups 1 and 2, respectively. There was a significant difference in operative time, with a mean (SD) operative time was 50.9 (11.2) in Group 1 vs 58.3 (12.4) min in Group 2 (P < 0.001). The success rate, defined as no retropulsion of stone fragments, was 97.7% in Group 2 vs 91.7% in Group 1 (P < 0.01). Complications were minor and comparable between the groups. There was no difference in hospital stay between the groups, but the cost assessment favoured Group 2. CONCLUSION: We found that our modified-basket stone entrapment technique compared favourably with the Stone Cone to guard against stone retropulsion during ureteroscopic pneumatic lithotripsy. Our modification to the basket was found to be feasible, efficient, safe, reproducible and cost-effective in preventing proximal stone migration. This procedure is particularly suitable in cost-limited environments.