A 64 channel 3T array coil for highly accelerated fetal imaging at 22 weeks of pregnancy

Abstract

MRI is an attractive tool for fetal imaging due to its unique ability to provide detailed anatomical and physiological data in an inherently safe manner. In practice, the problem of unpredictable and nonrigid fetal motion limits fetal MRI to fast single shot T2 weighted sequences such as HASTE, which have poor tissue contrast, low SNR, and cannot provide detailed physiological information. In this work, we designed, built, and tested a semi-adjustable anatomically shaped 64 channel array coil for fetal imaging at 22 weeks of pregnancy. The coil's performance was compared to that of the vendor's standard configuration consisting of an 18 channel flexible body array and 16 channels from a 32 channel spine array. The fetal coil provides roughly 5% better SNR in the fetal brain region of an anthropomorphic phantom and allows increasing SENSE acceleration factor from R = 4 to R = 5 in the right-left direction and R = 3 to R = 4 in the head-foot direction.