An Electrically Long Ultra-High Field MRI Volume Body Coil Design

We propose a 2-dimensional cylindrical high-pass ladder (2D c-HPL) coil and exploit the added second dimension in a longitudinal direction to create a body-sized volume coil with a length of 91 cm for use in ultra-high-field (UHF) magnetic resonance imaging (MRI). Theory, circuit model, and in-silico results show that this architecture exhibits improved transmit field inhomogeneity (6.44%), decreased specific absorption rate (0.014 W/kg), and improved specific absorption rate (SAR) efficiency (0.59 μT/√W/kg). This could prove particularly useful for whole-body and spinal-cord imaging, among others, and could open up new pathways for clinical diagnostics in UHF MRI.