The authors describe in a group of 200 patients with clinical symptoms of acute renal colic CT signs of ureterolithiasis, their importance and frequency. They evaluated the presence of concrements (size and site) and indirect signs (enlargement of the calico-pelvic system and ureters, perirenal „stranding“ and „rim-sign“). Ureterolithiasis was detected by CT examination in 156 (78%) patients, concrementswere not found in 44 (22%) patients.Thefindingwasfalsely positive in 2 patients, falsely negative in 3 patients. In 8 they supplemented spiral CT with a contrast substance. They detected 168 concrements in the pyeloureteral transits 15 (9%): in the upper third of the ureter in 43 (26%), in the middle portion of the ureters in 27 (16%) and in the lower third of the ureters in 83 (49%). The minimal size of concrements was 2 mm, the maximal size 17 mm. Concrements 2–5 mm in size were found in 98 patients (58%), concrements size 6–12 mm in 64 (38%) and concrements size 13–17 mm in 6 patients (4%). Enlargement of the calico-pelvic systemand ureter was found in 151 (89%), perirenal dense strips – „stranding“ in 52 (30%) patients and local expansion of the ureteral wall – „rim-signs“ in 34 (20%) patients. In 186 patients examined by ultrasound they detected concrements in 28 (15%), in 158 (85%) patients concrements were not detected in the ureter. The finding was falsely positive in 16, falsely negative in 108 patients. Calico-pelvic systems and ureters were enlarged in 146 (76%) patients. On plain images of the kidneys and urinary bladder the authors detected contrast concrements in 44 (28%) of 160 patients. Concrements were not detected in 116 patients (72%). A falsely positive finding was recorded in 11 a falsely negative one in 18 patients. In 42 patients with a renal colic the authors used excretory urography by which they proved ureterolithiasis in 25 (60%), in 17 cases (40%) the finding was negative, in 4 patients falsely positive and in 5 falsely negative.

        Key words: ureterolithiasis – renal colic – ultrasound examination – X-ray picture of kidneys and urinary bladder – excretory urography – spiral (helical) CT examination – perirenal „stranding“ – „rim-sign“