A new pulse sequence to visualize slow flow.

K-I Gjesdal; J C Hellund; T Storaas; J-T Geitung

doi:10.1007/s10334-004-0045-9

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A new pulse sequence to visualize slow flow.

K-I Gjesdal·J C Hellund·T Storaas·J-T Geitung

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Abstract

The purpose of this paper is to present a new pulse sequence for visualizing slow flow. The new sequence consists of an initial Stejskal-Tanner flow sensitization part followed by a DEFT pulse and a spoiler gradient. A single-shot TSE readout train is then applied to sample the NMR signal. The sequence was initially tested using a simple flow phantom. To verify potential clinical use, both flow-sensitive MRCP and cerebrospinal fluid (CSF) images were produced. The phantom study proved the sequence sensitivity to flow in the range 0-1 cm/s. bVE-factors 1.5, 3, 6 and 12 were chosen. Within this flow velocity range, the signal dropped as predicted theoretically. This indicates that the method can be used to quantify flow. All anatomical features seen in a standard MRCP sequence were identified and the methods sensitivity to CSF flow was demonstrated by sagital images of the head. A new pulse sequence sensitive to slow flow has been developed.

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K-I Gjesdal, J C Hellund, T Storaas, J-T Geitung. 2004-08-30. A new pulse sequence to visualize slow flow.. https://doi.org/10.1007/s10334-004-0045-9

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