Lisette van Dam

Introduction 9 1 MR-NCTI may also be useful in the diagnostic management of upper extremity deep vein thrombosis (UEDVT), where CUS examination is hindered by overlying anatomic structures. The alternative diagnostic imaging test is contrast venography, which has several disadvantages including radiation exposure and risk for contrast allergic reactions. 7 In Chapter 5 , the results of the Selene study are provided, in which the diagnostic accuracy of MR-NCTI for the diagnosis of UEDVT was evaluated. Another setting where MR-NCTI could be a valuable diagnostic test is in portal vein thrombosis (PVT). Differentiation between acute and chronic thrombosis is of paramount importance in the management of PVT, since the anticoagulant strategy in patients with acute PVT differs of that in patients with chronic thrombosis. 8 It is however not always possible with currently available imaging tests to make this distinction. As MR imaging of the portal veins can be more challenging than of the veins in the extremities due to bowel movements and the presence of intestinal air, we performed a study to identify the most optimal MR-NCTI sequence for PVT imaging ( Chapter 6 ). In Chapter 7 , an overview of different imaging techniques including MR-NCTI and their diagnostic accuracy in suspected acute cerebral vein thrombosis (CVT) is provided. Based on our studies and increasing experience with MR-NCTI, this technique is now more and more used to guide treatment decisions in other settings, such as in the patients in Chapter 8 and Chapter 9 . The first patient ( Chapter 8 ) was suspected of an acute CVT but had an inconclusive CT and MR venography. The second patient described in Chapter 9 had an extensive aortic thrombosis on CT angiography of unknown age, and a strong contraindication to anticoagulant treatment. The last chapters of this thesis focus on the application of CT in the diagnostic and prognostic management of acute PE. CT pulmonary angiography (CTPA) is the current diagnostic imaging of choice for the diagnosis of PE. 9 New CT techniques have been developed in recent years including techniques that can provide perfusion or iodine maps, representing the hemodynamic and functional impact of PE. This so-called CT pulmonary perfusion (CTPP) imaging may have an added value on top CTPA reading for initial risk stratification of acute PE. In Chapter 10 , the correlation between perfusion defects on CTPP and symptoms at presentation as well as short-term adverse outcome was assessed. Furthermore, as extensive perfusion defects on CT at the time of PE diagnosis may also correlate to long- term symptoms and outcome 10 , we evaluated the association between perfusion defects on CTPP at initial PE-diagnosis and persistent symptoms, including dyspnea, chest pain, functional impairment and adverse outcomes after 3-months of follow-up in Chapter 11 . CTPA is also used in the diagnostic management of