MR-guided endovascular interventions: a comprehensive review on techniques and applications

The magnetic resonance (MR) guidance of endovascular interventions is probably one of the greatest challenges of clinical MR research. MR angiography is not only an imaging tool for the vasculature but can also simultaneously depict high tissue contrast, including the differentiation of the vascular wall and perivascular tissues, as well as vascular function. Several hurdles had to be overcome to allow MR guidance for endovascular interventions. MR hardware and sequence design had to be developed to achieve acceptable patient access and to allow real-time or near real-time imaging. The development of interventional devices, both applicable and safe for MR imaging (MRI), was also mandatory. The subject of this review is to summarize the latest developments in real-time MRI hardware, MRI, visualization tools, interventional devices, endovascular tracking techniques, actual applications and safety issue

Hospital Implementation and Acceptance of Minimally Invasive Autopsy

To boost the rate of postmortem investigation, we introduced a minimally invasive autopsy (MIA) procedure, consisting of an MRI- and a CT-scan, combined with CT-guided biopsies, as an alternative to conventional autopsy. In this thesis we discuss the diagnostic performance and acceptation of the MIA-procedure

Improving heart transplantation care

In this dissertation we investigate ways to improve the care for heart transplantation patients. First, we investigate the waiting list mortality and the potential of Donation after Circulatory Death (DCD) heart transplantation or ‘heart in a box’. We found that the waitlist mortality is high, but DCD heart transplantations have a great potential in the Netherlands. Secondly, the incidence and treatment of certain diseases that can occur after heart transplantation are investigated. For example, kidney failure seems to be prevalent, which is best treated with a kidney transplantation. Moreover we found an association between kidney function before transplant and cancer after transplantation. Also the results of the Dutch paediatric heart transplantation programme is evaluated demonstrating good results with excellent quality of life. In the last part we investigate the use of CT scans in heart transplantation recipients. According to the guidelines, the coronary arteries of these patients should be evaluated every year (since these patients normally don’t feel chest pain, and coronary artery disease (called CAV in heart transplant patients) is prevalent), preferably with coronary angiography. However, this is an invasive method with risks. So we investigated whether or not CT scans are a good alternative, which was confirmed in our studies. Further investigations correlated a fat layer around the heart to CAV and investigated the incidence of reduced bone density and liver fat using the CT scan

Improving heart transplantation care

In this dissertation we investigate ways to improve the care for heart transplantation patients. First, we investigate the waiting list mortality and the potential of Donation after Circulatory Death (DCD) heart transplantation or ‘heart in a box’. We found that the waitlist mortality is high, but DCD heart transplantations have a great potential in the Netherlands. Secondly, the incidence and treatment of certain diseases that can occur after heart transplantation are investigated. For example, kidney failure seems to be prevalent, which is best treated with a kidney transplantation. Moreover we found an association between kidney function before transplant and cancer after transplantation. Also the results of the Dutch paediatric heart transplantation programme is evaluated demonstrating good results with excellent quality of life. In the last part we investigate the use of CT scans in heart transplantation recipients. According to the guidelines, the coronary arteries of these patients should be evaluated every year (since these patients normally don’t feel chest pain, and coronary artery disease (called CAV in heart transplant patients) is prevalent), preferably with coronary angiography. However, this is an invasive method with risks. So we investigated whether or not CT scans are a good alternative, which was confirmed in our studies. Further investigations correlated a fat layer around the heart to CAV and investigated the incidence of reduced bone density and liver fat using the CT scan

Radiation doses and associated risks from x-ray guided cardiac catheterization procedures in children and young adults

PhD ThesisCardiac catheterizations are an essential procedure in the management of patients with congenital and acquired heart conditions. However, associated radiation doses are often high, raising concerns over potentially increased cancer risks. Neither the radiation doses, nor the associated risks, have been adequately investigated in young people undergoing these procedures. A cohort was established of around 13,500 patients aged under 22 years who have undergone cardiac catheterizations in England. Organ doses were estimated based on a dosimetry system utilising data from Monte Carlo simulations. Doses were highest for the lungs (median: 17.6 millisieverts, mSv) and heart (13.6 mSv), while doses to bone marrow (2.6 mSv) and the thyroid (0.7 mSv) were relatively low. Radiation doses have fallen by a factor of up to ten during the study period. The results were compared to equivalent figures derived from physical measurements. Uncertainties in dose estimates were calculated. These were around ±30%, though were potentially much higher for breast dose. The risk of cancer in relation to estimated doses was calculated using BEIR VII risk models. For examinations conducted using modern equipment, these risks are around 1 in 1700. A small epidemiological analysis was performed, suggesting a nearly threefold increased risk of cancer in the cohort, compared to the general UK population. There are a number of reasons to suggest that this increase was primarily not related to radiation exposure, most notably the large impact of transplantation and likely associated immunosuppressant use. Despite the high cancer incidence, the overall survival in the cohort was high, at around 91% after 30 years. Conclusion: The study provides the first large scale estimation of organ doses from cardiac catheterizations among this age group. Rates of cancer among this patient group are high, although this is appears to be mostly due to factors other than radiation exposure.British Heart Foundatio