Value of ultrasound in persistent flank pain.

Urinary tract stones were present in 41 patients out of 54 who presented with recurrent or persistent flank pain. Ultrasound showed pelvicaliceal dilatation in 95.1% of these patients. Ultrasound is a safe, quick, reliable and cost effective diagnostic tool in such cases. Intravenous urography should be reserved for cases which need surgical intervention.