Advances in imaging vascular inflammation

Inflammation is central to the pathogenesis of many vascular diseases. Despite an understanding of the natural history, predicting progression and acute complications remains an important clinical challenge in both atherosclerosis and aortic aneurysms. Current means of monitoring rely mainly on structural information, such as the extent of luminal stenosis on coronary angiography or maximum aneurysm diameter on ultrasonography. Although often useful in making clinical decisions about intervention, such measures do not always correlate well with the risk of acute complications. As an example, the degree of luminal obstruction correlates poorly with the risk of future coronary plaque rupture and, similarly, aneurysm size does not account entirely for the subsequent rate of expansion and risk of rupture. It might be possible to improve risk prediction using imaging modalities that focus on the underlying disease processes rather than their consequences. This article reviews non-invasive imaging techniques that track inflammation within the arterial wall as applied to atherosclerosis and abdominal aneurysms. These all aim to improve risk prediction, to highlight the underlying pathology non-invasively and to permit the testing of new therapeutic agents against vascular disease.