Magnetic resonance imaging detection of extraluminal enterally administered gadopentetate dimeglumine in a rat model of intestinal ischemia

We assessed whether intestinal ischemia would result in transudation of orally administered gadopentetate dimeglumine into the peritoneal cavity.Twenty-eight rats were anesthetized and midline laparotomy was performed. Animals were divided into four groups: control, ligation of a single mesenteric arcade, ligation of six consecutive arcades, and ligation of the anterior mesenteric artery (analogous to the superior mesenteric artery in humans). A 1.0-ml enteric bolus of gadopentetate dimeglumine diluted with sterile water (1:1) was given via gavage. Magnetic resonance imaging was performed 2 hr after laparotomy and reviewed for the presence of intraperitoneal gadopentetate dimeglumine by two experienced observers. Animals were sacrificed 24 hr after surgery for pathologic examination.Four animals died prior to sacrifice. The bladder had a grossly high signal in all cases, implying some degree of intravascular absorption of the contrast material. A correlation was found between increasing mean radiology scores and increasing numbers of ligated vessels. The intraperitoneal signal tended to be higher in experimental animals than in control animals. Histologic damage was more severe in experimental animals (ischemic changes extending deeper into the intestinal wall) than in control animals.Direct visualization of spilled gastrointestinal gadopentetate dimeglumine helped discriminate ischemic from control rats in this model.