Abstract:
:In this study, a spin- and gradient-echo echo-planar imaging (SAGE EPI) MRI pulse sequence is presented that allows simultaneous measurements of gradient-echo and spin-echo dynamic susceptibility-contrast perfusion-weighted imaging data. Following signal excitation, five readout trains were acquired using spin- and gradient-echo echo-planar imaging, all of them with echo times of less than 100 ms. Contrast agent concentrations in brain tissue were determined based on absolute R2* and R(2) estimates rather than relative changes in the signals of individual echo trains, producing T(1)-independent dynamic susceptibility-contrast perfusion-weighted imaging data. Moreover, this acquisition technique enabled vessel size imaging through the simultaneous quantification of R2* and R(2), without an increase in acquisition time. In this work, the concepts of SAGE EPI pulse sequence and results in stroke and tumor imaging are presented. Overall, SAGE EPI combined the advantages of higher sensitivity to contrast agent passage of gradient-echo perfusion-weighted imaging with better microvascular selectivity of spin-echo perfusion-weighted imaging.
journal_name
Magn Reson Medjournal_title
Magnetic resonance in medicineauthors
Schmiedeskamp H,Straka M,Newbould RD,Zaharchuk G,Andre JB,Olivot JM,Moseley ME,Albers GW,Bammer Rdoi
10.1002/mrm.23195subject
Has Abstractpub_date
2012-07-01 00:00:00pages
30-40issue
1eissn
0740-3194issn
1522-2594journal_volume
68pub_type
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