Venous thromboembolism (VTE) encompasses pulmonary embolism (PE) and deep vein thrombosis (DVT). DVT most commonly occurs in the deep veins of the lower extremity but can also occur in the veins of... Show moreVenous thromboembolism (VTE) encompasses pulmonary embolism (PE) and deep vein thrombosis (DVT). DVT most commonly occurs in the deep veins of the lower extremity but can also occur in the veins of upper extremity, abdomen and cerebrum. As symptoms of VTE are nonspecific, the diagnosis of VTE is based on diagnostic tests, including clinical decision rules (CDR), D-dimer tests and imaging. Although the diagnostic management of VTE has greatly advanced in recent years with the introduction of novel CDRs and high-sensitive D-dimer tests, the diagnosis may still be challenging in certain settings. The latter is mainly caused by the indirect way of thrombus visualisation by current imaging tests, such as by showing incompressibility with compression ultrasonography (CUS) or a filling defect on contrast-enhanced computed tomography (CT) or magnetic resonance imaging (MRI).This thesis focuses on challenging settings for diagnosing VTE, including suspected recurrent ipsilateral DVT, upper extremity DVT, cerebral vein thrombosis and portal vein thrombosis. We studied a novel imaging technique called Magnetic Resonance Non-Contrast Thrombus Imaging (MR-NCTI) and its application in these different VTE settings. Show less
Studies in this thesis focused on the use of MRI in patients with early inflammatory arthritis. Studies were focused on: the diagnostic value of MRI, predictive value of MRI findings for the... Show moreStudies in this thesis focused on the use of MRI in patients with early inflammatory arthritis. Studies were focused on: the diagnostic value of MRI, predictive value of MRI findings for the development of erosions, associations between age and MRI findings, the use of MRI for the development of new disease activity scores and patient reported outcomes in patients with rheumatoid arthritis. Show less
Spondyloarthritis (SpA) is a heterogeneous group of rheumatic diseases, characterized by sacroiliac-joint inflammation (sacroiliitis), peripheral and extra-articular complaints. The lack of... Show moreSpondyloarthritis (SpA) is a heterogeneous group of rheumatic diseases, characterized by sacroiliac-joint inflammation (sacroiliitis), peripheral and extra-articular complaints. The lack of diagnostic criteria makes diagnosing SpA challenging, yet, classification criteria are available. We tested the performance (sensitivity, specificity) of various classification criteria; the recently developed Assessment of SpondyloArthritis international Society (ASAS) criteria outperformed all other criteria. We investigated the discrepancies in interpretation MRIs and conventional radiographs on the presence of sacroiliitis; agreement on radiographic sacroiliitis between different readers is only moderate, but agreement regarding sacroiliitis on MRI is substantial. Rheumatologists take into account all clinical and laboratory results in addition to the imaging results in the diagnostic process. The diagnostic Berlin algorithm - in which all relevant results are taken into account __ can assist rheumatologists. We proposed a modification of this algorithm, which is accepted by ASAS and also included in the recently published guidelines for the diagnosis and treatment of SpA by the Dutch Society for Rheumatology. Besides, we performed systematic literature reviews, forming the base for the update of the ASAS management recommendations. With these results, SpA-patients can be recognized earlier, offering better treatment options and better outcomes. However, further improvements of care for SpA-patients are necessary. Show less
