Lisette van Dam

Chapter 6 102 MR-NCTI optimization in PVT patients 3D T1 TFE and 3D T1 Dixon FFE sequences were used to evaluate the patient with acute PVT and two patients with chronic PVT ( Table 2 ). 3D T1 TFE and 3D T1 Dixon FFE showed a high signal intensity in all abdominal vein segments with acute thrombosis diagnosed on CT venography ( Figure 2 ). In the two patients with chronic PVT both sequences showed no increased signal intensity in the portal or mesenteric veins ( Figure 3 ). The expert panel was able to confirm the diagnosis of acute PVT on the combined two MR-NCTI sequences and to exclude acute PVT in the two patients with chronic thrombosis. The combination of 3D T1 TFE and 3D T1 Dixon FF was thus judged optimal for locating and differentiating acute from chronic PVT with good image quality and short scanning time (10-15 minutes). Figure 2A-F. Coronal computed tomography (CT) and magnetic resonance imaging (MRI) of the abdomen of a patient diagnosed with acute thrombosis in portal and mesenteric veins; A. CT image after intravenous contrast administration in portal-venous contrast phase shows a large luminal filling defect in the portal vein (arrow). B. MRI, 3D T1 TFE image shows a high signal intensity in the portal vein compatible with acute thrombus (arrow). C. MRI, 3D T1 Dixon FFE (water-only) image shows a high signal intensity in the portal vein (arrow). D. CT image after intravenous contrast administration shows extensive filling defects inmesenteric veins (arrow) with increased attenuation of the surrounding mesenteric fat (encircled). E. MRI, 3D T1 TFE image shows a high signal intensity in the mesenteric veins compatible with acute thrombus (encircled). F. MRI, 3D T1 Dixon FFE (water-only) image shows a high signal intensity in the mesenteric veins (encircled).