Blood velocity estimation feasibility using high resolution time-resolved MR sequences

摘要

Blood velocity quantification is a challenge for vascular flow observation and arterial pathogenesis comprehension. In this context, magnetic resonance dynamic sequences could be used for spatial velocity encoding. On one hand, phase contrast techniques use spins phase modification for velocity information extraction. On the other hand, time of flight (TOF) technique has a high temporal resolution, but it is still considered a vascular visualization technique. The aim of this study is to check feasibility to estimate blood velocity from gradient echo TOF-based images. This is advantageous as high temporal resolution (≪10 ms) has the potential to produce more precise exploration of vessel, and blood movements. This work represents an experimental analysis of MR signal behavior as a function of velocity, in fast gradient echo TOF-based sequence. The study of this relationship''s shape is necessary for later velocity quantification methods design. MR signal behavior is studied for a full scale of velocity, and reproducibility is checked. Imaging parameters influence is also reported. High temporal resolution, blood velocity estimation feasibility are finally discussed.