A New Approach Using Manganese-Enhanced MRI to Diagnose Acute Mesenteric Ischemia in a Rabbit Model: Initial Experience

Purpose. Manganese-enhanced MRI (MEMRI) has been applied to a wide range of biological and disease research. The purpose of the study was to use MEMRI to diagnose the acute mesenteric ischemia (AMI). Methods. The institutional experimental animal ethics committee approved this study. To optimize the dose of Mn(2+) infusion, a dose-dependent curve was obtained using Mn(2+)-enhanced T (1) map MRI by an intravenous infusion 2.5–20 nmol/g body weight (BW) of 50 nmol/L MnCl(2). The eighteen animals were divided into control, sham-operated, and AMI groups. AMI models were performed by ligating the superior mesenteric artery (SMA). T (1) values were measured on T (1) maps in regions of the small intestinal wall and relaxation rate (ΔR (1)) was calculated. Results. A nonlinear relationship between infused MnCl(2) solution dose and increase in small intestinal wall ΔR (1) was observed. Control animal exhibited significant Mn(2+) clearance over time at the dose of 15 nmol/g BW. In the AMI model, ΔR (1) values (0.95 ± 0.13) in the small intestinal wall were significantly lower than in control group (2.05 ± 0.19) after Mn(2+) infusion (P < 0.01). Conclusion. The data suggest that MEMRI shows potential as a diagnostic technique that is directly sensitive to the poor or absent perfusion in AMI.