Sridar Narayanan, Ph.D

Lecturer - Magnetic Resonance Spectroscopy Lab

I obtained my PhD in Neurological Sciences at McGill University under the mentorship of Prof. Douglas Arnold. My thesis work helped to define the importance of axonal injury in multiple sclerosis (MS) and to characterize the evolution of axonal injury over the course of the disease. Advances in the precise measurement of brain volume (thanks to collaborations with Dr. Louis Collins and his lab) enabled us to quantify the development of global and regional atrophy, to define the relationship of atrophy to changes in the density of our neuronal marker, N-acetylaspartate (NAA) and to develop a composite index of total axonal injury and loss. Understanding the evolution of axonal injury and tissue damage in MS is necessary to understand the evolution of the chronic disability that usually occurs in MS and the pathogenesis of the secondary progression that often develops and is resistant to immunomodulatory therapies. I continue to work with Dr. Arnold applying advanced MR techniques such as magnetization transfer imaging (MTI), magnetic resonance spectroscopy (MRS) and functional MRI (fMRI) to the study of multiple sclerosis (MS). I am involved in a number of research projects that include: investigating the relationship of fatigue in MS to cerebral functional reorganization; studying the neuroimaging features of Canadian children with clinically isolated demyelinating syndromes (a collaboration with Dr. Brenda Banwell, HSC, Toronto); using quantitative magnetization transfer imaging (in collaboration with Dr. Bruce Pike and his lab) to study the dynamics of remyelination and demyelination in MS; and studying the imaging correlates of fatigue in MS and post-polio syndrome (a collaboration with Dr. Daria Trojan, MNI). In addition, over the last few years I have gained extensive experience developing and supervising the implementation of MRI protocols (including MTR and MRS sub-studies) in multicenter clinical studies of MS.