The findings, reported in this month’s Archives of Neurology, were derived from Dr. Jeffrey Isner’s study of patients with arterial disease severe enough to possibly require amputation. Funded by Genzyme, the study’s aim was to improve circulation by injecting vascular endothelial growth factor to grow blood vessels. One patient, whom Dr. Drasko Simovic called “very observant,” noticed that the numbness that used to spread across much of his leg had shrunk to a small patch…