ELSC cordially invites you to the lecture given by:
Dr. Rita Schmidt
Department of Neurobiology, WIS
On the topic of:
“Towards high spatial and/or temporal resolution fMRI at ultra-high field 7T human MRI”
The recent push towards ultra-high (magnetic) fields in Magnetic Resonance Imaging (MRI) is expected to change the face of biomedical imaging. Recent studies employing state of the art 7 T MRI scanners achieved submillimeter resolution in 3D anatomical imaging of the human brain. However, the higher field also comes with new challenges, especially since we want to acquire the images with high spatial or temporal resolution to study the human brain function. These challenges include complex RF field distribution in the region of interest as well as higher static field inhomogeneity. To realize the benefits of the ultra-high field MRI, we need to develop new pulse sequences accelerating the acquisition, designing new RF coils and developing new biomarkers. For localized excitation in the brain, we develop novel multi-channel RF transmit capabilities and artificial materials designed especially for MRI applications. Translating the new methods for human brain imaging, my lab develops phantoms with relevant brain mimicking properties. Then, we combine these tools aiming to study the human brain in-vivo, scanning human volunteers during task. I will share with you our recent advances utilizing the new 7T human MRI scanner that was recently installed in the Weizmann Institute. We demonstrate a spatial resolution of 0.4 mm in anatomical images and a 1mm in-plane resolution for functional MRI. Comparison of fMRI at 7T to 3T shows that the task related change in the measured signal is increased and that localization is improved. Although the fMRI response is known to be slow, due to the hemodynamic response, we can exploit the increase in temporal resolution for better statistics. We examined 0.5 seconds repetition time acquiring fMRI signal during visual localizer task; using 8-times acceleration achieved by simultaneous multi-slice acquisition. Further study of 7T MRI can offer new opportunities for in-vivo brain functional studies.