Ultra-high-resolution imaging with a clinical MRI

Magnetic resonance imaging (MRI) has been used in clinical applications for several years. It offers a physician excellent anatomic detail and tissue characterisation. Within the past decade, advances in MRI have allowed us to image with a submillimeter, in-plane resolution. Achieving such reduction in voxel volume requires novel technological developments in every aspect of the MRI acquisition process: radio frequency (RF) and gradient hardware, and pulse sequence software. We have developed new techniques for inserting a custom-designed and custom-built, high-strength gradient coil into an existing clinical MR imager. Such inserts can produce strong gradient fields that lead to maximum spatial resolution and excellent signal sensitivity. Here, we describe the interfacing and calibration methods that we have developed for our custom insert into a 1.5 T General Electric MR scanner and show that all the tests have met the specifications of the clinical gradient coil. The implementation of our method allows for switching between clinical and research modes without having to purchase and maintain another MR system.