The alternating bidirectional versus the standard approach during shock wave lithotripsy for upper lumbar ureteric stones: a randomized controlled trial.

Purpose: To compare the outcome of shock wave lithotripsy (SWL) for upper lumbar ureteric stones using the alternating bidirectional approach versus the standard approach during the first session.

Methods: Our study was a randomized controlled trial including patients with single radio-opaque stone < 1 cm located in the upper lumbar ureter (from the ureteropelvic junction till the level medial to the lower margin of the kidney). SWL was conducted using electromagnetic Dornier Gemini Lithotripter. In group 1, patients were treated with the alternating under and over-table approach during the first session only and if other sessions were needed, the standard under-table approach was used. In group 2, patients were treated with the standard under-table approach during all sessions. Stone disintegration after the first session was assessed by kidney-ureter-bladder X-ray, renal ultrasonography and noncontrast computed tomography. Moreover, the incidence and severity of postoperative complications were evaluated.

Results: Forty-eight patients in each group completed the study. Patient demographics and stone characteristics were comparable in both groups. Complete disintegration was achieved in 41.7% of patients in group 1 versus 18.8% in group 2 (P = 0.021). Stone-free rate (SFR) was 58.3% and 20.8% in group 1 and 2 respectively (P = 0.001). The mean session time was 56.42 min in group 1 versus 46.35 min in group 2 (P < 0.001). There was no significant difference in postoperative complications.

Conclusion: Stone disintegration and SFR after the first SWL session are higher when using the alternating bidirectional approach for upper lumbar ureteric stones at the expense of longer procedural duration.

Trial Registration: ClinicalTrials identifier (ID: NCT03243682), clinicaltrials.gov.