Plain abdominal radiography with transabdominal native tissue harmonic imaging ultrasonography vs unenhanced computed tomography in renal colic

OBJECTIVE To compare plain film kidney, ureter and bladder radiography (KUB) with transabdominal native tissue harmonic imaging ultrasonography (NTHI-US) vs unenhanced computed tomography (CT) for the diagnosis of urinary calculi in patients with acute flank pain. In all, 112 patients who presented to the urological department with clinical suspicion of ureteric calculi were included. These patients had KUB with NTHI-US and unenhanced CT. Of the 112 patients, 14 were lost to follow-up and therefore excluded. For the remaining 98 patients (53 men, 45 women; mean age 43.3 years, range: 19-74) the KUB with NTHI-US findings were compared with the CT findings, which served as the 'gold standard'. PATIENTS AND METHODS In all, 75 patients were confirmed to have ureteric calculi. KUB with transabdominal NTHI-US detected 72 of the 75 patients with calculi (sensitivity 96%, specificity 91%, and accuracy 95%). Unenhanced CT detected urolithiasis in all 75 patients (sensitivity, specificity and accuracy of 100%). Both techniques showed further extra-urinary pathologies. RESULTS In the first paper in this section, the authors from Austria compare plain film plus transabdominal native-tissue harmonic ultrasonography with unenhanced CT for the diagnosis of urinary calculi in patients with acute flank pain. In this prospective study, they found that CT is the most accurate method of diagnosis, but that the other method of diagnosis compared favourably, with excellent results. CONCLUSION This prospective study shows that CT is the most accurate technique for detecting urolithiasis. However, KUB with transabdominal NTHI-US is an alternative to unenhanced CT with comparable results.