Relative merits of ultrasound and intravenous urography in the investigation of the urinary tract.

Three hundred and fifty adult patients referred for intravenous urography were entered into a prospective double blind trial comparing intravenous urography with real time ultrasound. The study was performed to clarify the relative merits of the two techniques. Our results show that ultrasound and a plain abdominal radiograph should be the examination of first choice in most circumstances. This is particularly so in vague abdominal pain and in recurrent urinary tract infections where intravenous urography can usually be omitted or used only as a secondary investigation for further evaluation of abnormal ultrasound findings. In acute renal colic, intravenous urography should be the primary investigation. In macroscopic haematuria, initial examination by ultrasound would reliably diagnose mass lesions, show whether the lesion is cystic or solid and assess possible spread. Normal ultrasound does not exclude haematuria due to ureteric lesions or bladder lesions and intravenous urography is recommended.