Effective treatment to prevent disability MS has been largely non-existent due to a poor understanding of the relevant pathophysiologic mechanisms. The purpose of the study is use novel PET and MRI techniques to study acute multiple sclerosis (MS) lesion. We will use a Magnetic Resonance Imaging (MRI) imaging sequence (programmed set of parameters and magnetic gradients) which will measure myelin and iron within lesions. Positron Emission Tomography (PET) is another test which may be more detailed information about factors causing damage within MS lesions. MRI is a test approved by FDA. A PET scan is a routine clinical imaging procedure useful for the diagnosis and to monitor response to treatment in subjects with neurological diseases. But the radioactive drugs or imaging probes (chemical substances) that will be used for the PET in this study are still investigational in patients with MS. They have been used to study many other neurological diseases and are safe but since they are not used in clinical practice are still investigational for this study

We believe that PET using radioactive imaging markers, [11C] DPA713 will provide a more detailed picture of your brain and will provide more information on the brain inflammation (DPA713). This information may be useful in assessing the role of inflammation on progressive disease. You can be on any treatment for your MS during the study.

The purpose of this study is to utilize multiple novel imaging techniques to identify specific mechanisms of tissue injury in MS lesions. By utilizing and developing imaging markers of known pathophysiologic relevance and quantifying their impact on demyelination and neuronal/axonal loss, we will develop a framework to define therapeutic targets to prevent damage and promote repair within lesions. With this framework, we provide tools to study the efficacy of novel therapeutics in MS clinical trials.

You will also have the option to receive an additional PET scan, which aims to assess the correlation between hypoxia and multiple sclerosis. Hypoxia, or deprivation of adequate oxygen, has been associated with MS, and there is evidence suggesting that a hypoxia-inflammation cycle contributes to the disease. We believe this additional PET scan may provide insight into the correlation between hypoxia and MS.