Spreading Cerebral Hypoperfusion during Migraine Headache

To the Editor: The report by Woods et al. (Dec. 22 issue)¹ on spreading oligemia as demonstrated by positron-emission tomography (PET) during a spontaneous episode of migraine confirms previous observations made on the basis of conventional studies of cerebral blood flow, as discussed by Olesen in the accompanying editorial.² It is a giant step, however, to conclude that this observation can be equated with “spreading depression,” which is primarily an observation in experiments with animals. Besides, one could ask how spreading depression leads to the clinical features of migraine — specifically, pain, the most important symptom. What is the clinical.