The serial effect of iodinated contrast media on renal hemodynamics and oxygenation as evaluated by ASL and BOLD MRI.
Contrast-induced nephropathy is a prevalent cause of renal failure, and the mechanisms underlying this injury are not fully understood. We utilized noninvasive functional MRI in order to determine the serial effect of a single administration of iodinated contrast media (CM) on renal hemodynamics and oxygenation. Fifteen rabbits were randomized to receive an intravenous injection of CM (i.e. iopamidol-370; 6 ml kg(-1) body weight) or an equivalent amount of 0.9% saline. Both arterial spin-labeling and blood oxygen level-dependent imaging sequences were performed at 24 h before and at intervals of 1, 24, 48 and 72 h after injection to obtain serial renal blood flow (RBF) and relative spin-spin relaxation rate (R(2)*). Results showed that, in the iopamidol group, the mean cortical RBF decreased at 1 h (p = 0.04 vs baseline), reached its minimum at 24 h (p = 0.01) and gradually returned to baseline by 48 h (p = nonsignificant, NS). The outer medullary RBF decreased to its minimum by 24 h (p = 0.00) and remained less than baseline until 72 h. R(2)* in inner stripes was dramatically increased at 1 h (p = 0.00), remained elevated at 24 h (p = 0.05), but returned to baseline by 48 h (p = NS). R(2)* values within the cortex and outer stripes and inner medulla were slightly increased, but the changes did not reach a statistical significance (p = NS). Saline did not produce positive change in either RBF or R(2)* within different compartments of the kidney. We conclude that iopamidol is associated with a relatively longer-term hypoperfusion in whole kidney and decreased oxygen level in the inner stripes of the outer medulla.
Department of Radiology, Peking University First Hospital, Beijing, China.
Yudong
Y
Zhang
Jing
J
Wang
Xuedong
X
Yang
Xiaoying
X
Wang
Jue
J
Zhang
Jing
J
Fang
Xuexiang
X
Jiang
D000818:Animals; D003287:Contrast Media / Q000008:administration & dosage / Q000494:pharmacology; D006439:Hemodynamics / Q000187:drug effects*; D007455:Iodine / Q000008:administration & dosage / Q000494:pharmacology; D007479:Iopamidol / Q000008:administration & dosage / Q000494:pharmacology*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D010100:Oxygen / Q000097:blood*; D010477:Perfusion; D011817:Rabbits; D012077:Renal Artery / Q000187:drug effects* / Q000378:metabolism; D012079:Renal Circulation / Q000187:drug effects*; D013113:Spin Labels
D003287:Contrast Media; D013113:Spin Labels; D007455:Iodine; D007479:Iopamidol; D010100:Oxygen