Visualization of urinary tract dilatation: value of single-shot MR urography.
The purpose of this study was to evaluate detection of urinary tract dilatation, depiction of obstruction level and determination of cause with single-shot MR imaging in an acquisition time of 2.8 s. Heavily T2-weighted single-shot MR images in 50 patients with ureterohydronephrosis as suspected by ultrasound were prospectively compared with IV urography and clinical outcome. Imaging techniques were obtained within a maximum time interval of 4 h and assessed independently on the same day. Single-shot MR urography was able to demonstrate dilatation and obstruction levels in 96 % of urinary tracts in accordance with X-ray urograms. In 4 patients with a unilaterally negative IV urogram, obstruction levels were demonstrated in single-shot MR urography. Single-shot MR urography did not depict 2 of 7 collecting systems with mild dilatation and contralateral undilated ureters were not adequately visible. Single-shot MR urography consistently visualizes dilated urinary tracts and obstruction levels in moderate and severe dilatation. Single-shot MR urography may be an alternative for IV urography in cases of renal impairment, when iodinated contrast or the application of X-rays is contraindicated, and may help in avoiding direct ureteropyelography. Single-shot MR urography rarely allows determination of the cause of urinary tract dilatation.
Reuther
G
G
Abteilung Bildgebende Diagnostik, Privatklinik und Ambulatorium Döbling, Heiligenstädter Strasse 57-63, A-1190 Vienna, Austria.
Kiefer
B
B
Wandl
E
E
D000328:Adult; D004108:Dilatation, Pathologic / Q000175:diagnosis / Q000209:etiology; D005260:Female; D006801:Humans; D006869:Hydronephrosis / Q000175:diagnosis* / Q000209:etiology; D007669:Kidney Calculi / Q000150:complications / Q000175:diagnosis; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D012680:Sensitivity and Specificity; D014517:Ureteral Obstruction / Q000175:diagnosis* / Q000209:etiology; D014567:Urography