Speaker: Neal K. Bangerter, Ph.D., Radiological Sciences Laboratory, Department of Radiology, Stanford University

Title: Applications and Advances in Sodium MRI for Cartilage and Cancer

Abstract: MRI has emerged as a leading method for the imaging of articular cartilage, with the potential to provide both high-resolution morphological information and detect biochemical and physiological changes. New MRI techniques such as T2 mapping, T1-rho, dGEMRIC, and sodium MRI can detect early deterioration of the cartilage matrix prior to any visible changes in morphology, an important step in the development of treatments for osteoarthritis. However, these techniques are not without their drawbacks: T2 relaxation techniques are not sensitive to the earliest degenerative changes, dGEMRIC scans can be prohibitively long and require the administration of contrast agents, T1-rho suffers from power-deposition limitations, and sodium MRI suffers from limited resolution and low SNR.

The recent availability of high-field MRI scanners (3T and above), advances in gradient and coil hardware, and the development of rapid, SNR-efficient 3D MR sequences has made sodium MRI feasible in vivo with reasonable SNR at higher resolutions. In addition to applications in cartilage, sodium MRI shows promise in the characterization of cancerous tumors and assessment of tumor viability. Recent work has shown sodium MRI to be effective at gauging tumor response to therapy, and the possibility of improving breast MR specificity with sodium MR has been proposed.

This presentation will provide an overview of the current state-of-the-art in cartilage MRI, and then focus on new developments in sodium MRI that show promise for improving assessment of cartilage health. Adaptation of these sodium MRI techniques for tumor characterization and viability will also be discussed, and preliminary results in breast cancer patients presented.