A Miniature Flexible Coil for High-SNR MRI of the Pituitary Gland

Clinical magnetic resonance imaging (MRI) of the pituitary gland sometimes fails to detect small pituitary tumors due to limited signal-to-noise ratio (SNR) and spatial resolution. Thus, neurosurgeons may need to resort to surgical exploration and systematic slicing of the pituitary gland to identify the small pituitary tumors. In this work, we designed a single-loop miniature flexible coil that can be surgically positioned millimeters from the pituitary gland, enabling high-SNR pituitary MRI. We investigated the spatial distributions of the image SNR of the miniature coil, via both numerical simulation and phantom experiments. We also explored the feasibility of increased SNR within the pituitary gland based on simulated surgical placements. Compared to the commercial head coil, our miniature coil achieved up to a 19-fold SNR improvement within the region of interest, and the simulation and phantom experiment reached a good agreement, with an error of 1.1% ± 0.8%. High resolution MRI scans further demonstrated the visual improvement of the miniature coil against the commercial head coil. The cross-validation of the simulation and the phantom experiment showed the potential of using the numerical simulation model to accelerate the coil design prototyping and iteration and to optimize coil design in the future.