Abstract:
PURPOSE:To track variations in the deformation of the arterial wall noninvasively by estimating the accumulated displacement and strain over a cardiac cycle may provide useful indicators of vascular health. METHODS:In this paper, we propose an approach to track a region of interest (ROI) locally and estimate arterial stiffness variation in a familial hypercholesterolemic swine model of spontaneous atherosclerosis that allows for systematic and reproducible study of progression of the disease mechanism. RESULTS:Strain and displacement indices may be derived from the variations of the accumulated displacement and accumulated strain (obtained from the gradient of the accumulated displacement) over a cardiac cycle to predict not only the likelihood of developing vascular diseases, but also the sites where they may occur. Currently, an ROI thickness value of less than one mm within the arterial wall is necessary for the axial accumulated displacement and strain to obtain reproducible estimates. CONCLUSIONS:Accumulated axial displacement and strain estimation on the artery wall shown in this paper indicate the repeatability of these measurements over several cardiac cycles and over five familial hypercholesterolemic swine. Our results also demonstrate the need for a small region of interest within the arterial walls for accurate and robust estimates of arterial function.
journal_name
Med Physjournal_title
Medical physicsauthors
Ge W,Krueger CG,Weichmann A,Shanmuganayagam D,Varghese Tdoi
10.1118/1.4722746subject
Has Abstractpub_date
2012-07-01 00:00:00pages
4483-92issue
7eissn
0094-2405issn
2473-4209journal_volume
39pub_type
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