Magnetic resonance imaging at 7 Tesla with dedicated radiofrequency coils :Application to cervical cord and knee

Magnetic Resonance (MR) Imaging is a valuable tool in the diagnosis and monitoring of various musculoskeletal pathologies. New Ultra-High Field (UHF) 7 T MRI systems, with their enhanced Signal-to- Noise Ratio, may offer increased image quality in terms of spatial resolution and/or shorter scanning time compared to lower field systems. However, these benefits can be difficult to obtain because of increased radio-frequency (RF) inhomogeneity, increased Specific Absorption Rate (SAR) and the relative lack of specialized and commercially available RF coils compared to lower field systems. This study reports the feasibility of imaging in bones and cartilages at UHF with a 7 T MR scanner available at the IMAGO7 Foundation (Pisa, Italy). Dedicated radio-frequency coils for proton imaging have been designed, developed, optimized for different anatomical regions and validated in vivo, and are now ready for clinical research studies. The performance of the RF coil prototypes in targeting different anatomical regions are also demonstrated, obtaining images of the neck (the cervical cord) and of the knee (trabecular bone and cartilages).