Eur J Radiol. 2011 Nov;80(2):378-86. doi: 10.1016/j.ejrad.2011.02.044. Epub 2011 Apr 5.

Persistent renal enhancement after intra-arterial versus intravenous iodixanol administration.

Chou SH, Wang ZJ, Kuo J, Cabarrus M, Fu Y, Aslam R, Yee J, Zimmet JM, Shunk K, Elicker B, Yeh BM.

Source

Department of Radiology, University of California San Francisco, 505 Parnassus Avenue, San Francisco, CA 94143-0628, United States.

Abstract

PURPOSE:

To examine the clinical significance of persistent renal enhancement after iodixanol administration.

METHODS:

We retrospectively studied 166 consecutive patients who underwent non-enhanced abdominopelvic CT within 7 days after receiving intra-arterial (n=99) or intravenous (n=67) iodixanol. Renal attenuation was measured for each non-enhanced CT scan. Persistent renal enhancement was defined as CT attenuation>55 Hounsfield units (HU). Contrast-induced nephropathy (CIN) was defined as a rise in serum creatinine>0.5 mg/dL within 5 days after contrast administration.

RESULTS:

While the intensity and frequency of persistent renal enhancement was higher after intra-arterial (mean CT attenuation of 73.7 HU, seen in 54 of 99 patients, or 55%) than intravenous contrast material administration (51.8 HU, seen in 21 of 67, or 31%, p<0.005), a multivariate regression model showed that the independent predictors of persistent renal enhancement were a shorter time interval until the subsequent non-enhanced CT (p<0.001); higher contrast dose (p<0.001); higher baseline serum creatinine (p<0.01); and older age (p<0.05). The route of contrast administration was not a predictor of persistent renal enhancement in this model. Contrast-induced nephropathy was noted in 9 patients who received intra-arterial (9%) versus 3 who received intravenous iodixanol (4%), and was more common in patients with persistent renal enhancement (p<0.01).

CONCLUSION:

Persistent renal enhancement at follow-up non-contrast CT suggests a greater risk for contrast-induced nephropathy, but the increased frequency of striking renal enhancement in patients who received intra-arterial rather than intravenous contrast material also reflects the larger doses of contrast and shorter time to subsequent follow-up CT scanning for such patients.