Pancreas and peripancreatic vessels: Effect of imaging delay on gadoliniumenhancement at dynamic gradient-recalled-echo MR imaging

PURPOSE: To investigate the effect of imaging delay on gadolinium enhanceme nt of the pancreas and peripancreatic vessels at dynamic gradient-recalled- echo,,magnetic resonance (MR) imaging of the pancreas. MATERIALS AND METHODS: Dynamic MR images were obtained after intravenous bo lus injection of gadopentetate dimeglumine in 75 patients with no pancreati c malignancies. Test-bolus imaging was performed to determine aortic transi t time in individual patients. Patients were randomly assigned so that the middle of kappa space was acquired at 5, 15, 25, 35, or 45 seconds after ar rival of contrast arterial in the abdominal aorta. Mean signal intensities of pancreas, liver, and peripancreatic vessels were measured, and images we re qualitatively assessed by two radiologists. RESULTS: The best pancreatic enhancement occurred at a delay of 15 seconds (P < .05). The best enhancement of the liver and peripancreatic vessels occ urred at 25 seconds or later (P < .05). Qualitatively, the best images of t he pancreas were obtained at 15 seconds, and the best images of the liver a nd peripancreatic vessels were obtained at 25 seconds or later. CONCLUSION: Biphasic imaging at 15 and 45 seconds or later after arrival of contrast material in the abdominal aorta is a practical method for acquisi tion of high-quality dynamic gradient-recalled-echo MR images of the pancre as.