Detection of reperfused ischemia of the rat intestine: value of magnetic resonance imaging with small-molecular-weight dysprosium and gadolinium chelates.
OBJECTIVE
The authors assessed whether the small-molecular-weight magnetic resonance (MR) imaging contrast agents dysprosium diethylenetriamepentaacetic acid bismethylamide (sprodiamide injection), which enhances T2*, and gadolinium diethylenetriamepentaacetic acid bismethylamide (gadodiamide injection), which enhances T1, could improve the detection of reperfused ischemia of the rat intestine.


METHODS
Eighteen rats were subjected to vascular occlusion of the distal ileum for 30 minutes, followed by reperfusion. Ten minutes after reperfusion, T1- and T2-weighted spin-echo (SE) images were obtained before and after administration of sprodiamide, gadodiamide, or both. The same imaging protocol was applied in another group of 18 rats subjected to 10 minutes of occlusion and reperfusion. Histologic examination of the intestine was performed after MR imaging.


RESULTS
Villous injury (ie, denudation) was observed in most cases after 30 minutes of occlusion, but not after 10 minutes of occlusion. After 30 minutes of occlusion, the superficial part of the ischemic intestine was hyperintense to the normal intestine on unenhanced T2-weighted images. Administration of sprodiamide improved the contrast between the normal and ischemic intestine on T2-weighted images, and administration of both gadodiamide and sprodiamide improved the contrast on T1- and T2-weighted images. After 10 minutes of occlusion, no contrast was discernible before or after contrast material administration.


CONCLUSIONS
These results suggest that the detection of reperfused intestinal ischemia of sufficient duration to cause villous injury can be improved by using sprodiamide injection alone or in combination with gadodiamide.
Van Beers
B E
BE
Department of Radiology, Université Catholique de Louvain, St-Luc University Hospital, Brussels, Belgium.
Goudemant
J F
JF
Oksendal
A
A
Jamart
J
J
Delos
M
M
Thiran
J P
JP
Demeure
R
R
Pringot
J
J
Maldague
B
B
D000818:Animals; D003287:Contrast Media; D004419:Dysprosium; D005682:Gadolinium; D019786:Gadolinium DTPA; D007089:Image Enhancement; D007275:Injections, Intravenous; D007422:Intestines / Q000098:blood supply* / Q000473:pathology; D007511:Ischemia / Q000175:diagnosis* / Q000473:pathology; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008970:Molecular Weight; D009942:Organometallic Compounds; D004369:Pentetic Acid / Q000031:analogs & derivatives*; D051381:Rats; D017208:Rats, Wistar
D003287:Contrast Media; D009942:Organometallic Compounds; C061756:sprodiamide; D004419:Dysprosium; D004369:Pentetic Acid; C064925:gadodiamide; D005682:Gadolinium; D019786:Gadolinium DTPA