Simulation of Phase-Contrast MRI Intravoxel Velocity Standard Deviation (IVSD) Mapping
نویسندگان
چکیده
Introduction: Disturbed blood flow, characterized by velocity fluctuations, accompanies many cardiovascular diseases and may contribute to their progression [1]. Phase-contrast (PC) MRI intravoxel velocity standard deviation (IVSD, σ) mapping permits the quantification of the intensity of velocity fluctuations (turbulence intensity) [2]. This is achieved by exploiting how the presence of multiple spin velocities within a voxel affects the MR signal magnitude under the influence of a bipolar gradient. To further develop PC-MRI IVSD mapping, tools for optimization, quality control and validation are needed. We have previously presented an Eulerian-Lagrangian approach for the simulation of PC-MRI velocity measurements of turbulent flow [3]. This approach is here utilized for the simulation of PC-MRI IVSD mapping of turbulent stenotic flow. For validation, the simulation is compared with an in-vitro IVSD measurement.
منابع مشابه
Simulation of phase contrast MRI of turbulent flow.
Phase contrast MRI is a powerful tool for the assessment of blood flow. However, especially in the highly complex and turbulent flow that accompanies many cardiovascular diseases, phase contrast MRI may suffer from artifacts. Simulation of phase contrast MRI of turbulent flow could increase our understanding of phase contrast MRI artifacts in turbulent flows and facilitate the development of ph...
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