![Mayo Clinic home page [logo]](/images-global/mayologo.gif)
Give. Touch. Transform.
Share this site with others using one of these sharing tools.
To link to this article, paste this block of HTML code onto your webpage.
Guidelines for sites linking to mayoclinic.orgUniversity of Chicago, Chicago, IL
Beth Israel Deaconess Medical Center, Harvard University, Boston, MA
Harvard-Longwood Neurological Training Program, Boston, MA
American Board of Psychiatry and Neurology
Professor of Neurology
Cerebrovascular disease
See a listing of publications on PubMed, a service of the National Library of medicine.
See a description of research activities.
Learn about treatment of diseases and becoming a patient. Read more about medical services.
.
