Value of intravenous urography before shockwave lithotripsy in the treatment of renal calculi: a randomized study.

PURPOSE

To study the impact of preprocedure intravenous urography (IVU) on the outcome of SWL for renal stones.

PATIENTS AND METHODS

Two hundred patients with radiopaque renal stones <or=2.5 cm on plain radiographs and no or mild renal backpressure on ultrasonographic examination were allocated randomly to two treatment groups. Group I (n = 100) had IVU before the start of SWL, whereas patients in the second group (n = 100) underwent SWL without IVU. Thirteen patients in the IVU group and seven patients in the no-IVU group were excluded from the study. Patients in both groups received the same treatment and follow-up protocols. Intraoperative and postoperative complications were evaluated in all patients. An endpoint assessment by plain film was done 3 months after the conclusion of treatment to evaluate the success and stone-free rates.

RESULTS

The success rate (81.6% in group 1 v 77.4% in group 2), stone-free rate (65.5% v 62.3%), re-treatment rate (59.8% v 69.9%), auxiliary-procedure rate (6.9% v 5.4%), and complication rate (11.5% v 14%) were similar in the two groups.

CONCLUSION

It is not necessary to obtain an IVU for patients who have renal calculi with no or minimal back pressure before scheduling them for SWL, thus minimizing the cost, avoiding exposure to contrast medium, and reducing radiation exposure.