1. Department of Radiology and Biomedical Imaging, Yale School of Medicine, PO Box 208042, Tompkin's East 2, New Haven, CT 06510.
2. Department of Neurology, Yale School of Medicine, New Haven, CT.
3. Department of Emergency Medicine, Yale School of Medicine, New Haven, CT.
4. Department of Health Policy and Management, Yale School of Public Health, New Haven, CT.
5. Yale Center for Clinical Investigation, Yale School of Medicine, New Haven, CT.