Lisette van Dam

Magnetic resonance thrombus imaging in portal vein thrombosis 6 99 of the scans was performed and compared with the clinical presentation and the results of other imaging (Doppler US, CT venography or MRI). The scan results were assessed for image quality, venous location, and either presence or absence of acute thrombosis. RESULTS Literature search We identified the following MRI sequences: 3-dimensional T1 Turbo Field Echo (3D T1 TFE), 3D Turbo Spin Echo with Spectral Attenuated Inversion Recovery (3D TSE SPAIR) and T1 high-resolution isotropic volume excitation (THRIVE) and techniques: black-blood, Dixon and Principle of Selective Excitation Technique (ProSET) which could be suitable for portal vein imaging. A 3D T1 TFE sequence was shown to be highly accurate for the diagnosis of first deep vein thrombosis and the differentiation of acute deep vein thrombosis from chronic residual vascular abnormalities in the leg. 8-10 Hence, this sequence seemed promising for the differentiation of acute from chronic PVT. Furthermore, in a pilot study 3D T1 TFE and 3D TSE SPAIR sequences successfully confirmed the diagnosis of arm vein thrombosis when compared to ultrasonography or contrast venography. 11 The advantages of 3D TSE-SPAIR over 3D T1 TFE were a higher spatial resolution of the vessel wall and less high signal artefacts in arteries caused by inflow effects. Therefore, both 3D T1 TFE and 3D TSE SPAIR may be suitable for portal vein imaging. THRIVE sequences may also be a promising MR-NCTI technique in PVT with potential good contrast resolution between high signal intensity of an acute thrombus and low signal intensity intravascular. 12 The black-blood technique was successfully used to identify deep vein thrombosis of the leg and in cerebral vein thrombosis. 13,14 With this technique the signal from flowing blood is nullified and highlights static anatomy including thrombi. 15 Because of known good contrast resolution between thrombus and flowing blood, we hypothesized that combining the black-blood technique with 3D TSE SPAIR may be suitable for portal vein imaging.