Abstract:
:High-signal artifacts produced by cerebrospinal fluid (CSF) flow can adversely affect fluid-attenuated inversion recovery (FLAIR) imaging of the brain and spinal cord. This study explores the use of a nonslice-selective inversion pulse to eliminate CSF flow artifacts together with a technique called "K-space Reordered by Inversion-time for each Slice Position" (KRISP) to achieve constant contrast in a multislice acquisition. Theory shows that with this method the CSF point spread function (PSF) has a minimum at the center and attenuated side lobes, providing CSF suppression, but residual edge signals remain. The PSF for brain is only mildly attenuated and signals for extended regions are not attenuated. KRISP FLAIR sequences were assessed in 15 patients (10 brain and five spinal cord cases). The images showed reduced CSF and blood flow artifacts and higher conspicuity of the cortex, meninges, ventricular system, brainstem, and cerebellum when compared with conventional FLAIR sequences.
journal_name
Magn Reson Medjournal_title
Magnetic resonance in medicineauthors
Herlihy AH,Oatridge A,Curati WL,Puri BK,Bydder GM,Hajnal JVdoi
10.1002/mrm.1198subject
Has Abstractpub_date
2001-08-01 00:00:00pages
354-64issue
2eissn
0740-3194issn
1522-2594pii
10.1002/mrm.1198journal_volume
46pub_type
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