Personal tools
Document Actions

Peripheral Vascular Disease

A disease in the vasculature located outside the heart and brain is referred to as peripheral vascular disease (PVD). Typical peripheral vasculature includes pulmonary, iliac, femoral, carotid, popliteal and tibial arteries carrying blood to the kidneys, stomach, arms, legs and feet. PVD is caused by either a) atherosclerosis – a narrowing or blockage in the artery that occurs due to the deposition of fatty plaques on the inner wall, or b) arteriosclerosis – structural changes in the arterial wall causing inflammation or thickening of the artery wall. Such narrowing or thickening leads to a reduction of blood flow and a drop in pressure across the artery. Over time, if left untreated, PVD can lead to a terminal condition such as stroke or heart attack. Current diagnostic measures for PVD include Doppler ultrasound imaging, Magnetic resonance (MR) angiography, Computed tomography (CT) angiography and catheterization.

In addition to the above-mentioned clinical diagnostic procedures, computational modeling and simulation has gained increasing importance among the engineering community for medical research. Past and current research in the TEM Lab in this area focuses on improving computational models for assessing the functional and anatomical characteristics of diseased vasculature. For example, an inverse algorithm was developed to compute and predict the stresses in the artery wall under an intact (in vivo) condition in the human body (pre-stressed condition) using physiologic pulsatile pressure and flow in conjunction with a hyperelastic material model. The algorithm was initially developed and validated using a straight arterial segment of a canine femoral artery (idealized geometry), as shown in Figure 1. The pre-stressed arterial wall geometry, predicted by the algorithm was within 0.55% of the actual geometry obtained in vivo. Subsequently, the physiologic arterial wall pre-stress was used in assessing the pulsatile pressure-flow response of the artery. Coupled equations of wall deformation and flow conservation were solved using a computational finite element software. In addition to the idealized geometry, the inverse algorithm was implemented and tested on a patient-specific 3-dimensional geometry of the branched pulmonary arteries, shown in Figure 2, which was reconstructed from CT images of a human subject.

Additional research in this area is conducted by the TEM Lab to advance and develop novel techniques for diagnosis and treatment of peripheral vascular diseases.
 

idealised dog femoral artery

Figure 1. An in vivo idealized arterial wall geometry of a dog femoral artery

peripheral vascular disease_icon

Figure 2. Lumen surface of the branched pulmonary arteries obtained from geometry reconstruction

by Gavin D Souza last modified 2015-05-26 14:46