Delineation of upper urinary tract segments at MDCT urography in patients with extra-urinary mass lesions: retrospective comparison of standard and low-dose protocols for the excretory phase of imaging
- نوع فایل : کتاب
- زبان : انگلیسی
- مؤلف : Ulrike L. Mueller-Lisse & Eva M. Coppenrath & Thomas Meindl & Christoph Degenhart & Michael K. Scherr & Christian G. Stief & Maximilian F. Reiser &
- چاپ و سال / کشور: 2010
Description
Purpose Excretory-phase CT urography (CTU) may replace excretory urography in patients without urinary tumors. However, radiation exposure is a concern.We retrospectively compared upper urinary tract (UUT) delineation in low-dose and standard CTU. Material and methods CTU (1-2 phases, 120 KV, 4× 2.5 mm, pitch 0.875, i.v. non-ionic contrast media, iodine 36 g) was obtained with standard (14 patients, n=27 UUTs, average 175.6 mAs/slice, average delay 16.8 min) or lowdose (26 patients, n=86 UUTs, 29 mAs/slice, average delay 19.6 min) protocols. UUT was segmented into intrarenal collecting system (IRCS), upper, middle, and lower ureter (UU,MU,LU). Two independent readers (R1,R2) graded UUT segments as 1-not delineated, 2-partially delineated, 3-completely delineated (noisy margins), 4-completely delineated (clear margins). Chi-square statistics were calculated for partial versus complete delineation and complete delineation (clear margins), respectively. Results Complete delineation of UUT was similar in standard and low-dose CTU (R1, p>0.15; R2, p>0.2). IRCS, UU, and MU clearly delineated similarly often in standard and lowdose CTU (R1, p>0.25; R2, p>0.1). LU clearly delineated more often in standard protocols (R1, 18/6 standard, 38/31 low-dose, p>0.1; R2 18/6 standard, 21/48 low-dose, p<0.05). Conclusions Low-dose CTU sufficiently delineated course of UUT and may locate obstruction/dilation, but appears unlikely to find intraluminal LU lesions.
Eur Radiol (2011) 21:378–384 DOI 10.1007/s00330-010-1935-z Received: 10 March 2010 / Revised: 8 June 2010 / Accepted: 20 June 2010 / Published online: 30 August 2010
