Grant: Project Grant

Atherosclerosis development is multifactorial and involves the accumulation of lipids within the artery wall. At the early development stages of the disease, the cross-sectional area of the artery is not modified as only an inward vessel wall thickening is observed. With more advanced progression of the disease, partial and total artery blockage may occur thus impacting the flow of oxygen and nutrients to downstream organs. An occluding artery is known in the medical field as a stenosis, whereas the thickening of the artery wall at the origin of this flow obstruction or stenosis is labeled a plaque or an atherosclerotic plaque. Carotid arteries are particularly prone to atherosclerosis and the rupture of a plaque by mechanical stresses (due to the blood pressure and cyclic pulsation of the artery) can lead to the formation of a blood clot, its migration within the arterial system of the brain, leading to a subsequent stroke. Although knowledge on characteristics defining carotid plaques at risk has advanced, predicting rupture is very challenging. A few imaging methods have been developed for this objective, namely magnetic resonance imaging, X-ray computed tomography, positron emission tomography and ultrasound imaging. These technologies provide imaging biomarkers of risk but none of them aim imaging biomechanical stresses at the origin of plaque rupture. We developed a method that can directly image the deformation of the artery wall likely contributing to the initiation of plaque rupture. We are also developing quantitative ultrasound imaging methods to study plaque structural characteristics. The objective of our proposal is to further develop these methods to provide a computer platform to process ultrasound images and extract these new mechanical and tissue biomarkers for clinical evaluation of HIV patients at higher risk of atherosclerosis evolution and stroke.