## Abstract This review examines the way in which microscopic tissue parameters can affect MR experiments which are sensitive to diffusion. The interaction between the intraβ and extravascular as well as that between the intraβ and extracellular spaces is examined. Susceptibility gradients due to t
Effect of bulk tissue motion on quantitative perfusion and diffusion magnetic resonance imaging
β Scribed by Thomas L. Chenevert; James G. Pipe
- Publisher
- John Wiley and Sons
- Year
- 1991
- Tongue
- English
- Weight
- 294 KB
- Volume
- 19
- Category
- Article
- ISSN
- 0740-3194
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β¦ Synopsis
The effect of irreproducible bulk tissue motions upon quantification of tissue perfusion and diffusion was studied via computer simulation of random phase error in conventional phase-encoded perfusion/diffusion MRI. Simulations using acquisition parameters typical for human brain studies demonstrate that bulk motion irreproducibility of approximately 60 microns/s can produce phase instability on the order of 20 degrees which overwhelms estimates of perfusion fraction and produces significant errors in diffusion values. Bulk tissue motion control of the human brain via cardiac gating and substantial head restraint was studied by direct measurement of voxel phase stability. Phase instability of 10 degrees to 20 degrees was observed from right-to-left and anterior-to-posterior motions and significantly greater phase variability from superior-to-inferior motion. The spatial pattern of phase variability indicates the source is likely a mixture of cardiac pulsation and respiration.
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