Osteoarthritis of the knee is a chronic progressive joint disease leading to pain and loss of function in a considerable proportion of patients with great impact and consequences in the ageing... Show moreOsteoarthritis of the knee is a chronic progressive joint disease leading to pain and loss of function in a considerable proportion of patients with great impact and consequences in the ageing population of the industrialized world. Clinical symptoms and radiographs of the knee are normally used to monitor osteoarthritic changes in the knee. However, the correlation between radiographic osteoarthritic findings and clinical features is poor. Does MR imaging of the knee tell us more about the relation between osteoarthritic structural findings and clinical features? According to the present thesis, the answer is “No”. Most of the data presented in this thesis is based on a 1.5T longitudinal MR study called the “Genetica, Artrose & Progressie” (GARP) study. In the GARP study MR imaging findings were associated with clinical features of patients with OA, and it was concluded that there were no strong associations between the most important OA imaging findings and clinical features of patients with OA. These controversial findings are important findings with regards to future clinical trials, as it urges conservatism with regards to the idea of BME being an outcome measure for progression of the disease. Therefore, the current theses also strongly recommend a further quest to identify ideal parameters to quantify the progression of the disease. Show less
Neuropsychiatric systemic lupus erythematosus (NPSLE) is a rheumatologic disorder causing neurologic, psychiatric and/or psychologic symptoms. The most important clinical problems are the aspecific... Show moreNeuropsychiatric systemic lupus erythematosus (NPSLE) is a rheumatologic disorder causing neurologic, psychiatric and/or psychologic symptoms. The most important clinical problems are the aspecific nature of signs and symptoms, the limited knowledge on pathogenesis and the absence of a diagnostic gold standard. Magnetic resonance imaging (MRI) is considered the most important imaging modality of the brain in NPSLE patients. Abnormalities visible on conventional MRI appear anywhere in the brain, and may normalize, stabilize or increase with loss of brain parenchyma. Apart from conventional MRI sequences, in this thesis advanced MRI techniques such as magnetization transfer imaging (MTI) were also applied, which are more sensitive to microscopic brain damage invisible to the human eye. Microscopic brain damage in NPSLE appears mostly in the cortical gray matter and is associated with the presence of anticardiolipin antibodies. The final brain damage, as observed using different MRI techniques, consists of neuronal and axonal damage, atrophy, demyelination and gliosis. Changes in the total amount of microscopic brain damage as detected by MTI correlate with changes in clinical status. This thesis contributes to the knowledge on the pathogenesis of NPSLE, and illustrates that advanced and conventional radiological techniques can be helpful in making diagnostic and therapeutic decisions. Show less