1. 1Section of Neurosurgery and
2. 2Thayer School of Engineering, Hanover;
3. 3Dartmouth Medical School, Hanover, New Hampshire;
4. 4Ontario Cancer Institute, University of Toronto, Ontario, Canada; and
5. 5Departments of Pathology and Neurology, Georgetown University Medical Center, Washington, DC
6. 6Norris Cotton Cancer Center, Dartmouth-Hitchcock Medical Center, Lebanon;