Parallel Imaging Update: How Many Elements Do We Need?
Massachusetts General Hospital
Virtually all clinical coils utilize receive-only arrays with 4 to, more recently, 32 elements. Both sensitivity and accelerated encoding motivates even higher numbers of array elements. In the logical extension of this approach, the number of elements is increased ad infinitum and the size of the elements is reduced (to cover a fixed anatomical territory). With unlimited access to receive channels, a different paradigm emerges for RF coil design. We are just beginning to explore at what point the utility of this approach exhausts itself and what factors limit the gains in array coil SNR and acceleration capability.