James Burgess

Subject-specific modeling of intracranial aneurysms

Characterization of the blood flow patterns in cerebral aneurysms is important to explore possible correlations between the hemodynamics conditions and the morphology, location, type and risk of rupture of intracranial aneurysms. For this purpose, realistic patient-specific models are constructed from computed tomography angiography and 3D rotational angiography image data. Visualizations of the distribution of hemodynamics forces on the aneurysm walls as well as the intra-aneurysmal flow patterns are presented for a number of cerebral aneurysms of different sizes, types and locations. The numerical models indicate that there are different classes of intra-aneurysmal flow patterns, that may carry different risks of rupture.

Cerebral aneurysm hemodynamics modeling from 3D rotational angiography

Detailed knowledge of the hemodynamics in cerebral aneurysms is valuable not only for understanding their formation and rupture but also for clinical evaluation and treatment. However, important hemodynamic quantities are difficult to measure in vivo. In this paper a patient-specific method for modeling the hemodynamics of cerebral aneurysms from in vivo anatomical images is described, and the flow patterns in various kinds of intracranial aneurysms are presented. These models will be used to explore possible relationships between the blood flow patterns and the location, size and taxonomy of the aneurysms.

Multimodality image-based models of carotid artery hemodynamics (Cum Laude Poster Award)

Determination of the hemodynamics conditions in atherosclerotic carotid arteries is important for quantitative assessment of the severity of the disease. Since there are no reliable experimental methods to determine the in vivo wall shear stress distribution in the region of the stenosis, realistic patient-specific image-based finite element models are constructed. The purpose of this paper is to present validation studies based on multi-modality image data of patients with carotid artery disease. The velocity profiles and peak velocity at stenoses computed by the computational fluid dynamics models are in very good agreement with phase-contrast magnetic resonance and carotid Doppler ultrasound measurements, respectively.

Patient-Specific Modeling of Atherosclerotic Carotid Arteries From Multi-Modality Image Data

Estimation of the wall shear stress distribution in stenotic carotid arteries is important for assessing risk of stroke. Since there are no reliable experimental methods to determine wall shear stress distributions, realistic patient-specific computational fluid dynamics models are constructed from medical images. Anatomical and physiologic data are obtained from multiple image modalities including 3D rotational angiography, contrast-enhanced magnetic resonance angiography, carotid duplex ultrasound and phase-contrast magnetic resonance. These images are used to construct patient-specific finite element grids and to solve the incompressible Navier-Stokes equations under physiological pulsatile flow conditions. The detailed knowledge of the carotid hemodynamics derived from these models can be used to enhance our understanding of the relationship between flow patterns and symptoms, and ultimately risk of stroke. This methodology can also be used to correllate flow patterns with the outcome of endovascular procedures such as angioplasty and stenting.Copyright