CINCINNATI–A $51,000 grant will enable University of Cincinnati (UC) researchers to determine whether sophisticated new imaging technologies can help them achieve pinpoint placement of deep-brain stimulation electrodes in patients with Parkinson's disease. George Mandybur, MD, a neurosurgeon with the Mayfield Clinic and the UC Neuroscience Institute, is leading the pilot study, which will take place at University Hospital.
Mandybur and his team will use a 3-Tesla MRI scanner with high-resolution sequences, along with diffusion tensor imaging fiber tracking, in an attempt to quickly and accurately predict the size and position of the subthalamic nucleus, a small area deep within the brain. The size and location of the subthalamic nucleus can vary significantly from patient to patient.
Physicians have long known that by stimulating the subthalamic nucleus they can alleviate symptoms and improve the lives of some patients with Parkinson's disease. Traditionally, surgeons have located the target by using standard medical atlases and multiple preoperative and intraoperative imaging techniques, including 1.5-Tesla MRI. "But current methods have drawbacks," Mandybur says. "The borders of the subthalamic nucleus can be indistinct, to the extent that sometimes we cannot visualize the nucleus well."
To be certain that the electrodes are in the right place, surgeons have relied on electrophysiological confirmation, stimulating the target while the patient is awake and often making multiple passes through brain tissue. When surgery is prolonged in an effort to define the target, the risk of complications can increase.
In their study, Mandybur and his co-investigators will use new imaging modalities, including the more powerful 3-Tesla MRI and diffusion tensor imaging, which provides a map of critical white-matter tracts in the brain. White-matter tracts are electrical connections that should not be surgically disrupted.
The study will involve 20 patients at the James J. and Joan A. Gardner Center for Parkinson's Disease and Movement Disorders at the UC Neuroscience Institute. Funding comes from the Sunflower Revolution, an annual fundraiser and bike ride held in Cincinnati. The Sunflower event is a collaboration among the UC Neuroscience Institute, the University Hospital Foundation and the Davis Phinney Foundation of Boulder, Colo.
Mandybur's co-investigators are Gregory Toczyl, MD, a neurosurgeon and the 2008-2009 Davis Phinney-Donald Krumme Fellow in Parkinson's Disease and Movement Disorders; Jim Eliassen, PhD, and Jing-huei Chang, PhD, of the UC Department of Psychiatry; Fredy J. Revilla, MD, of the UC Department of Neurology; and James Leach, MD, of the Department of Radiology at Cincinnati Children's Hospital Medical Center.
The UC Neuroscience Institute, a regional center of excellence at UC and University Hospital, is dedicated to patient care, research, education and the development of new treatments for stroke, brain and spinal tumors, epilepsy, traumatic brain and spinal injury, Alzheimer's disease, Parkinson's disease, disorders of the nerves and muscles, disorders of the senses (swallowing, voice, hearing, pain, taste and smell), and psychiatric conditions (bipolar disorder, schizophrenia and depression).
The Mayfield Clinic is recognized as one of the nation's leading physician organizations for clinical care, education, and research of the spine and brain. Supported by 20 neurosurgeons, three neurointensivists, an interventional radiologist and a pain specialist, the clinic treats 20,000 patients from 35 states and 13 countries in a typical year.