Abstract #3328

RF Pulse Comparison for the Hybrid Gradient and Spin Echo EPI Pulse Sequence for fMRI

Brice Fernandez¹, Gavin Houston², Victor Spoormaker³, Marion Smits⁴, Michael Czisch³, Patrick Le Roux⁵

¹EMEA Research and Collaboration, Applied Science Laboratory, GE Healthcare, Munich, Germany; ²EMEA Research and Collaboration, Applied Science Laboratory, GE Healthcare, Rotterdam, Netherlands; ³RG Neuroimaging, Max Planck Institute of Psychiatry, Munich, Germany; ⁴Departement of Radiology, Erasmus MC - University Medical Centre Rotterdam, Rotterdam, Netherlands; ⁵EMEA Research and Collaboration, Applied Science Laboratory, GE Healthcare, Palaiseau, France

Hybrid gradient (GRE) and spin-echo (SE) pulse sequences are an interesting alternative to GRE functional MRI (fMRI). In this preliminary work, to minimize the difference between the GRE and the SE profile, two pairs of RF pulses (excitation and refocusing pulses) were designed, implemented and evaluated in a basic visual fMRI experiment. The results shows that a typical profile difference (<6%) between the SE and the GRE profile is not problematic in the context of fMRI. Our results give also some insight for further improvement of the RF pulse pair used in this hybrid pulse sequence.