Microscopic spin tagging (MiST) for flow imaging.

Silvia Olt; Peter Schmitt; Florian Fidler; Axel Haase; Peter M Jakob

doi:10.1007/bf02693843

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Microscopic spin tagging (MiST) for flow imaging.

Silvia Olt·Peter Schmitt·Florian Fidler·Axel Haase·Peter M Jakob

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Abstract

In this study, a new strategy for slow flow imaging is proposed. The basic idea is to generate flow contrast on a microscopic level below the spatial resolution of an imaging experiment. Since a microscopic spin tagging scheme is used, this concept is called MiST (Microscopic Spin Tagging). MiST is not a single specific measurement sequence, but rather a new flow sensitive preparation concept which is highly flexible and can be carried out in many ways. The common principle in all possible realizations of MiST is a periodic tagging of magnetization in thin planes (100-200 microm) within the imaging voxels by means of spatially selective RF-pulses. Therefore, flow sensitivity occurs via inflow of fresh spins on a microscopic scale. With this approach, short evolution times are sufficient to introduce inflow contrast and a spatial dependence of inflow times is avoided. The flow sensitive preparation and image orientation are also not connected as they are in conventional time-of-flight techniques. Another powerful feature of MiST is that it can be designed as a non-subtraction method, which results in no signal from stationary spins. Here we present a first realization of the MiST concept and its validation in quantitative flow measurements to demonstrate the feasibility of the proposed preparation concept.

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Arteries Blood Flow Velocity Feasibility Studies Image Enhancement Magnetic Resonance Imaging Phantoms, Imaging Rheology Sensitivity and Specificity Spin Labels Comparative Study Evaluation Study Journal Article Research Support, Non-U.S. Gov't Validation Study

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Silvia Olt, Peter Schmitt, Florian Fidler, Axel Haase, Peter M Jakob. 2002. Microscopic spin tagging (MiST) for flow imaging.. https://doi.org/10.1007/bf02693843

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