Meningeal Inflammation on 7T MRI as a Tool for Measuring and Predicting Ocrelizumab Response in Multiple Sclerosis

Multiple Sclerosis (MS) is an autoimmune disorder of the central nervous system. In MS, inflammation is known to attack areas of the brain, spinal cord, and optic nerves; resulting in disability. Current MRI technology provides an adequate view of the impact of MS on the "white matter" of the brain, which contains many of the connections between neurons. Quantification of lesions in the white matter due to MS are a standard part of clinical trials and clinical care in MS. However, it has long been known that MS not only can affect the white matter, but also the "gray matter," which contains the majority of the nerve cells in the brain and can cause inflammation in the meninges (the protective tissue that surrounds the brain and spinal cord). Autopsy studies have shown that the inflammation seen in the meninges is driven by a B-cells, a subset of white blood cells and that meningeal inflammation may be responsible for damage to the gray matter of the brain. Ocrelizumab is a new treatment for multiple sclerosis. This medication works by targeting and destroying circulating B-cells. It is thought that this may reduce the level of meningeal inflammation in patients with multiple sclerosis. By reducing meningeal inflammation, this medication may result in less damage to the gray matter and subsequently less disability in MS patients. In this study, the investigators will evaluate the use of a method on 7 tesla (7T) MRI to identify inflammation in the meninges as a potential predictor of response to ocrelizumab treatment for multiple sclerosis. Further, the investigators will evaluate if this MRI technique can be used to monitor the long-term effect of the medication on meningeal inflammation and the development of damage to the gray matter of the brain.