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PubMed · 9702706

Functional imaging by I0- and T2*-parameter mapping using multi-image EPI.

O Speck·J Hennig
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Abstract

A new functional imaging method has been developed and used to measure T2*- and initial intensity (I0)-parameter maps of multiple slices during activation of the cortex with high temporal resolution. Multiple echo-planar images (EPIs) are read out after a single excitation of the spin system, leading to several images with increasing effective echo times. Changes induced by primary visual stimulation in T2* and I0 were measured in eight subjects. Although stimulation-induced increases in I0 only occurred at short repetition times, T2* increased from 57.3 to 60.9 ms on average. The method combines the high stability of a single shot EPI experiment with the high information content of a multiecho acquisition. In addition, stimulation-induced changes in inflow can be easily separated from true blood oxygenation level dependent (BOLD) signal changes.

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ArousalBrain MappingCerebral CortexEcho-Planar ImagingEquipment DesignHumansImage Processing, Computer-AssistedMagnetic Resonance ImagingOxygen ConsumptionPattern Recognition, VisualSensitivity and SpecificityVisual CortexJournal Article

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O Speck, J Hennig. 1998. Functional imaging by I0- and T2*-parameter mapping using multi-image EPI.. https://doi.org/10.1002/mrm.1910400210

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