Maintenance of certification: part 2--continuous certification.

NeuroEndovascular Division, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, USA American Board of Radiology, Tuscon, Arizona, USA Mallinckrodt Institute of Radiology and the Departments of Neurology and Neurosurgery, Washington University School of Medicine, St Louis, Missouri, USA Rhode Island Hospital, Warren Alpert School of Medicine at Brown University, Providence, Rhode Island, USA Rush University Medical Center, University Neurosurgery, Chicago, Illinois, USA Department of Neurological Surgery, Neurological Institute, New York, New York, USA