Gd-BOPTA/Dimeg: Experimental disease imaging

The novel tissue‐specific contrast agent, Gd‐BOPTA/Dirmeg, was tested in MR imaging of experimental focal liver disease and of acute myocardial ischemia in rats. Directly implanted liver tumors and blood‐borne metastases were used as models for focal liver disease and occlusion of the lower anterior descending coronary artery as model for acute ischemia. The studies with implanted tumors, at a dose level of 250 μmol/kg, showed a very high (370%) and persistent (>2h) increase in the tumor‐liver contrast‐to‐noise ratio (CNR), owing to selective enhancement of normal liver parenchyma signal intensity. While all blood‐borne metastases showed a similar late CNR enhancement, some of them experienced early contrast loss due to transient signal intensity enhancement. In myocardial imaging. Gd‐BOPTA/Dimeg produced a signal intensity enhancement in normal myocardium and an injured area‐normal area CNR enhancement which were both much stronger and more presistent than those produced by Gd‐DTPA/Dimeg. © 1991 Academic Press, Inc.