Liang Zhan1, Neda Jahanshad1, Christophe Lenglet2, Bryon A. Mueller3, Guillermo Sapiro4, Noam Harel2, Kelvin O. Lim3, Paul M. Thompson1
1Department of Neurology, University of California, Los Angeles, Los Angeles, CA, United States; 2Center for Magnetic Resonance Research, University of Minnesota Medical School, Minneapolis, MN, United States; 3Dept. of Psychiatry, Univ. of Minnesota, Minneapolis, MN, United States; 4Department of Electrical and Computer Engineering, University of Minnesota, Minneapolis, MN, United States
High-field diffusion imaging can be used to map anatomical connectivity in the living brain, but little is known about how the resulting connectivity maps compare to those obtained at lower fields. Five young healthy subjects (two male, age: 32.414.6 years) were scanned at 3T and with a 7T protocol with 1.5mm isotropic voxels (called 7T-1.5mm below). To assess field strength effects while keeping voxel size constant, we also scanned 2 of the 5 subjects using a protocol called 7T-2mm for comparison purposes. Connections between rostral anterior cingulate and the lateral orbitofrontal, caudal middle frontal and rostral middle frontal cortex in the left hemisphere were more prominent at 7T-1.5mm, and showed the most significant differences by protocol. Smaller voxels allowed more connections to be recovered, particularly shorter ones, and this affected the relative prominence of different connections in the matrices.