Magnetic Resonance Imaging To Predict Outcomes In Aortic Aneurysms
The aorta is the main blood vessel that comes out of the heart and distributes blood to the whole body. In some people, the aorta becomes swollen (aneurysm) and bursts, especially as it passes through the abdomen. These 'abdominal aortic aneurysms' often occur without symptoms and can burst or rupture without warning. This usually leads to death and represents the thirteenth commonest cause of death in the United Kingdom. In this study, we are looking at a new technique that can look at the aortic aneurysm using magnetic resonance imaging; a technique that does not require x-rays or radiation. We have recently shown that, using magnetic resonance combined with a new imaging agent USPIO, we can detect 'hotspots' of activity in these aneurysms that seem to predict which aneurysms grow rapidly, and are therefore potentially at risk of rupture. We here propose to conduct a study in Edinburgh that will invite all patients who are under surveillance because of an aneurysm. We will image these patients using this novel technique and see if we can identify which patients burst their aneurysm, have an aneurysm that grows so large it needs to have surgery, or die. This will be important to establish as it will potentially lead to a new way of managing people that could ultimately save lives. This is particularly timely as national screening and surveillance programmes are currently being launched.
Abdominal Aortic Aneurysm
|Study Design:||Time Perspective: Prospective|
|Official Title:||Efficacy of Magnetic Resonance Imaging Using Ultrasmall Superparamagnetic Particles of Iron Oxide to Predict Clinical Outcome in Patients Under Surveillance for Abdominal Aortic Aneurysms|
- To determine if uptake ultrasmall superparamagnetic particles of iron oxide as determined by percentage R2* change between pre-and post-constant scan will predict abdominal aortic aneurysm growth and rupture in patients with abdominal aortic aneurysms. [ Time Frame: 2 yrs ] [ Designated as safety issue: No ]The change of R2* signal which is determined by the USPIO uptake within the issues will be used to assess the change between pre-and post contrast MRI scans. The investigators will assess if macrophage activity as determined by USPIO change predicts AAA growth and rupture
- Does USPIO uptake as determined by percentage change between pre-and post contrast scan co-relates with FDG PET standardised uptake values or tissue to background ratios. [ Time Frame: 2 yrs ] [ Designated as safety issue: No ]As per ethical approval, we have recruited patients under AAA PET study to look at USPIO correlation with 18F-FDG PET. The cellular inflammation can be assessed by USPIO uptake, whilst the metabolic activity can be determined by 18F-FDG PET. In this study, the investigators will determine if there is a correlation between the these two imaging modalties by comparing the R2* change using MRI and standardised uptake values using FDG PET.
|Study Start Date:||March 2011|
|Study Completion Date:||August 2012|
|Primary Completion Date:||August 2012 (Final data collection date for primary outcome measure)|
Abdominal Aortic Aneurysms
Patients will be recruited from the outpatient AAA surveillance population at the vascular unit in the Royal Infirmary of Edinburgh.Potential participation in the study will be completely asymptomatic from their AAA.
HYPOTHESIS We hypothesise that uptake of ultrasmall supraparamagnetic particles of iron oxide into the aortic wall will predict abdominal aortic aneurysm growth and clinical outcomes.
|Clinical Research Imaging Centre/ NHS LOTHIAN|
|Edinburgh, United Kingdom, EH16 4SB|
|Principal Investigator:||David Newby, MD PhD||University of Edinburgh|