Manganese (II) N,N'-dipyridoxylethylenediamine-N,N'-diacetate 5,5'-bis(phosphate): clinical experience with a new contrast agent.

Despite the many imaging techniques available to evaluate the liver, deficiencies persist. The choice of the optimal method is still controversial, with competing issues of safety, efficacy, and cost. Numerous strategies to improve the results of liver imaging have been pursued, including the application of tissue-targeted contrast agents to magnetic resonance imaging (MRI). Manganese (II) N,N'-dipyridoxylethylenediamine-N,N'-diacetate 5,5'-bis(phosphate) (Mn-DPDP) is one of several recently developed hepatobiliary agents, targeted to functioning hepatocytes. The Mn-DPDP-enhanced MRI has demonstrated promise in the clinical trials. Contrast-to-noise measurements have shown favorable results for Mn-DPDP-enhanced MR compared to non-enhanced T1- and T2-weighted images. The ability to characterize tumors of hepatocellular origin and an improved capability for lesion detection have also been demonstrated. Furthermore, the prolonged enhancement obtained with Mn-DPDP has extended the time during which effective contrast is maintained. Importantly, no clinically significant adverse events have been demonstrated. This report will detail the clinical experience with Mn-DPDP-enhanced MRI of the abdomen.