Timothy F. Witham, MD

Dr. Debraj “Raj” Mukherjee’s clinical focus is the treatment of patients with primary and metastatic brain lesions. His clinical work and research emphasize the development of individual treatment plans that optimize survival and quality of life in all patients. After receiving his medical degree from Dartmouth Medical School, Dr. Mukherjee was recruited to Johns Hopkins, where he studied epidemiology, biostatistics and clinical design at the Johns Hopkins Bloomberg School of Public Health and served as Director of the Neuro-Oncology Surgical Outcomes Laboratory in the Department of Neurosurgery. Dr. Mukherjee completed neurosurgery residency at Cedars-Sinai Medical Center, where he was named a Robert Wood Johnson Foundation Health & Society Scholar. He completed an open and endoscopic skull base fellowship with the Center for Skull Base Surgery at University of Pittsburgh Medical Center, where he was a Copeland Scholar. Throughout his career, Dr. Mukherjee has led patient-centered research pursuits in neuro-oncology including development of a national registry for patients with brain tumors, creation of disease-specific quality of life instruments for patients with skull base tumors, and development of innovative clinical trials in neuro-oncology. He leads the Meningioma, Brain Metastasis, and Neurosurgical Oncology centers at Johns Hopkins Medicine, and he serves as Assistant Residency Program Director for one of the largest neurosurgical training programs in the country. His work has been supported by the American Medical Association, Glioblastoma Foundation, National Institute on Aging, and National Cancer Institute. Dr. Mukherjee can be contacted at drraj@jhmi.edu.

Olurotimi Mesubi, M.B.B.S., M.P.H., is a cardiologist, specializing in clinical cardiac electrophysiology. He practices primarily in Baltimore, Maryland. He is an assistant professor of medicine in the Division of Cardiology at the Baltimore-based Johns Hopkins University School of Medicine.As a clinical cardiac electrophysiologist, Dr. Mesubi specializes in the diagnosis and treatment of cardiac arrhythmias, which are heart rhythm disorders that cause the heart to beat irregularly. He has particular interest and expertise in inherited arrhythmia disorders and channelopathies, such as long QT syndrome, Brugada syndrome, CPVT, muscular dystrophies and arrhythmogenic cardiomyopathies. Dr. Mesubi performs pacemaker and defibrillator implantations and complex catheter ablations for cardiac arrhythmias.His basic research focus explores the molecular mechanisms linking diabetes mellitus to atrial fibrillation.

Risheng Xu, M.D., Ph.D., is a fellowship-trained neurosurgeon with expertise in cerebrovascular and endovascular neurosurgery, and skull base pathologies. He treats patients with a wide range of cerebrovascular disorders such as cerebral aneurysms, subarachnoid hemorrhage, arteriovenous malformations, arteriovenous fistulas, carotid stenosis, cavernous malformations and moyamoya disease. He also treats skull base tumors such as acoustic neuromas (vestibular schwannomas) and meningiomas, and pain disorders such as trigeminal neuralgia.Dr. Xu completed his undergraduate studies at Harvard College, and attended medical school at the Johns Hopkins University School of Medicine, where he also obtained a Ph.D. in pharmacology and molecular sciences. He continued his residency training in neurosurgery at Johns Hopkins, and remained there to complete a fellowship in cerebrovascular and endovascular neurosurgery. Dr. Xu has been active in research throughout his training and has authored and co-authored numerous published studies. His basic science research endeavors focus on neuroinflammation after ischemic stroke and molecular mechanisms underlying trigeminal neuralgia. He has authored or co-authored over 100 manuscripts, and has published in journals such as Nature, Nature Communications, Science Advances, Science Signaling, Neuron, the Proceedings of the National Academy of Sciences (PNAS), the Journal of Neurosurgery, Neurosurgery and other journals. Clinically, he studies the long-term outcomes of patients with cerebrovascular disorders and trigeminal neuralgia.