Magnetic Resonance Imaging Using Ultrasmall Superparamagnetic Particles of Iron Oxide to Predict Clinical Outcome in Patients Under Surveillance for Abdominal Aortic Aneurysms
The aorta is the main blood vessel that comes out of the heart and rapidly distributes blood to the whole body. In some people, the aorta becomes swollen (an aneurysm) especially as it passes through the abdomen. These 'abdominal aortic aneurysms' (AAA) usually grow slowly without causing any symptoms, but they can sometimes burst or need to be fixed by an operation. Currently aneurysms are monitored by ultrasound scanning. In this research study, we want to see if magnetic resonance imaging (MRI) might be a better way of following patients who have an aneurysm. To do this, we will use a “contrast agent” (Ferumoxytol) that contains tiny iron filings that are eaten up by cells (called macrophages) in the wall of the aneurysm. We can then use the MRI scanner to get a picture of your aneurysm. In a small group of patients, we have recently shown that we can use this MRI scan to detect 'hotspots' in the wall of some aneurysms that seemed to grow more quickly than others. The aim of the current study is to confirm these findings in a larger group of patients and also to see whether MRI scanning can identify patients with aneurysms at risk of bursting or those that go on to need an operation.