Multi-detector CT urography: effect of oral hydration and contrast medium volume on renal parenchymal enhancement and urinary tract opacification--a quantitative and qualitative analysis.
OBJECTIVE
To assess the effect of oral hydration and contrast-medium volume on renal enhancement and urinary tract opacification in multi-detector CT urography.


METHODS
A total of 192 patients were assigned to different protocols with varying doses of contrast agent with and without oral hydration. The attenuation was measured in the renal parenchyma in the unenhanced, nephrographic and excretory phase, and in the urinary tract in excretory phase imaging, respectively. Opacification of the urinary tract was graded on volume rendered images.


RESULTS
Oral hydration did not significantly alter renal parenchymal enhancement in both the nephrographic and the excretory phase (p > 0.001), but significantly decreased mean attenuation of the urinary tract in the excretory phase (p < or = 0.001), and improved continuous opacification of all ureter segments (p < 0.01). Higher volumes of contrast medium improved renal parenchymal enhancement (p < or = 0.001) and continuous opacification of the urinary tract (p < or = 0.01).


CONCLUSIONS
Oral hydration leads to lower attenuation values in the urinary tract but improves the continuous opacification of the tract. Increase in contrast medium volume leads to higher renal parenchymal enhancement as well as to an increased continuous opacification of the urinary tract. Decrease in contrast medium volume cannot be compensated for by oral hydration in terms of parenchymal enhancement.
Szolar
Dieter H
DH
Diagnostikum Graz-Südwest, Weblinger Gürtel 25, 8054, Graz, Austria. ds@diagnostikum-graz.at
Tillich
Manfred
M
Preidler
Klaus W
KW
D000284:Administration, Oral; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003287:Contrast Media / Q000008:administration & dosage; D004305:Dose-Response Relationship, Drug; D005260:Female; D006801:Humans; D007668:Kidney / Q000000981:diagnostic imaging / Q000187:drug effects*; D008297:Male; D008875:Middle Aged; D011856:Radiographic Image Enhancement / Q000379:methods; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed / Q000379:methods*; D014551:Urinary Tract / Q000187:drug effects*; D014567:Urography / Q000379:methods*; D014570:Urologic Diseases / Q000000981:diagnostic imaging*; D014867:Water / Q000008:administration & dosage*; D055815:Young Adult
D003287:Contrast Media; D014867:Water
Radiology. 2002 Feb;222(2):353-60
11818599
Radiology. 1988 Jun;167(3):593-9
3363117
AJR Am J Roentgenol. 2006 Jan;186(1):122-9
16357390
Radiology. 2009 Feb;250(2):309-23
19188307
Rofo. 2001 Mar;173(3):176-80
11293855
AJR Am J Roentgenol. 2001 Oct;177(4):849-55
11566687
Radiology. 2005 Apr;235(1):116-23
15716388
AJR Am J Roentgenol. 1998 May;170(5):1261-7
9574598
Radiology. 2004 Jul;232(1):126-32
15220498
J Comput Assist Tomogr. 2001 May-Jun;25(3):343-7
11351181
Radiol Clin North Am. 2008 Jan;46(1):113-32, vii
18328883
Eur Radiol. 2006 Dec;16(12):2670-86
16953373
AJR Am J Roentgenol. 2006 Jan;186(1):136-40
16357392
Semin Ultrasound CT MR. 2004 Feb;25(1):41-54
15035531
Acad Radiol. 2001 Nov;8(11):1100-6
11721809
Radiology. 2002 Dec;225(3):783-90
12461262