Studies in Headache

Abstract

Introduction Studies on bulbar conjunctival vasodilatation and edema occurring during migraine headache have been described and commented upon elsewhere. 1 In the course of these investigations, in order more fully to evaluate the changes seen during a migraine headache attack, the bulbar conjunctival vessels of two healthy, normotensive young male subjects, who seldom, if ever, had headaches, were examined daily for 23 days. The examination was made by means of a Poser ophthalmic slit lamp at a magnification of ×47.5, and appropriate photographs were made. Certain solutions prepared in an isotonic phosphate buffer at a pH of 7.2 and topically applied were employed to assess vascular reactivity. The least concentration of topical levarterenol required to blanch capillaries was determined and was called the sensitivity threshold. In the 46 examinations made on the two healthy subjects no vasodilatation or migraine headache occurred. However, on five occasions there were increased arteriolar constriction