A Twisted Loop Coil for High Field MRI

Wolfgang Loew¹, Randy Giaquinto¹, Scott Dunn¹, Ronald Pratt¹, Diana Lindquist¹, Charles Dumoulin¹

A novel RF coil design for a 7T animal scanner was developed. The new approach uses a loop coil twisted around a cylindrical former. The RF homogeneity of this new design was compared to an identically-sized birdcage using B1 mapping, and found to be more uniform. SNR comparisons between the coils showed the expected sensitivity ratio between a linear and quadrature coil. The RF homogeneity and SNR characteristics of the new coil were evaluated in in-vivo mouse images acquired with the twisted loop design. The new coil has fewer parts and is easier to tune than a comparably-sized birdcage coil.