An integrated head immobilization system and high-performance RF coil for fMRI of visual paradigms at 1.5 T

A flexible quadrature radiofrequency coil that maximizes the signal-to-nois e ratio over the field of view of the human brain has been integrated into a head immobilization and visor system for fMRI at 1.5 T, Head motion is re duced by the visor that incorporates a head clamp and a simple visual sight ing system that provides feedback on head position. This system is demonstr ated in serial images by correction of deliberate head motions, The sensiti vity at the cortical surface of fMRI using blood oxygenation level dependen t contrast is increased significantly above that of the commercial rigid vo lume RF coil under the same acquisition conditions. This improved performan ce is demonstrated using visual activation and eye movement paradigms. (C) 1999 Academic Press.