Acute flank pain: comparison of non-contrast-enhanced CT and intravenous urography.

PURPOSE: To compare non-contrast-enhanced computed tomography (CT) and intravenous urography (IVU) in the evaluation of patients who present with acute flank pain and in whom ureteric obstruction is suspected.

MATERIALS AND METHODS: The findings at non-contrast-enhanced CT and IVU in 20 patients with acute flank pain were compared for the presence or absence of ureteric obstruction and delineation of ureteric stones.

RESULTS: Twelve of the 20 patients had non-contrast-enhanced CT and IVU findings consistent with ureteric obstruction. Of these 12 patients, five had a ureteric stone that was demonstrated on both non-contrast-enhanced CT scans and IVU radiographs, six had a stone that was depicted on non-contrast-enhanced CT scans only, and in one patient a stone could not be delineated definitively on either non-contrast-enhanced CT scans or IVU radiographs. Eight patients had findings at non-contrast-enhanced CT and IVU consistent with the absence of obstruction.

CONCLUSION: Non-contrast-enhanced CT is more effective than IVU in precisely identifying ureteric stones and is equally effective as IVU in the determination of the presence or absence of ureteric obstruction.