Annotations

There is as yet no good evidence that " histamine " headaches occur naturally, but they have been much used experimentally to study the nature of certain vascular headaches. An injection of histamine produces an ache, throbbing in character, all over the top of the head. The ache begins when the temporary rise of blood pressure following the injection has subsided, and there is evidence to show that it is due to an increased distension of the intracranial vessels with each cardiac systole. This headache can be abolished by raising the pressure of fluid in the subarachnoid space (or by spinning the patient head outwards in a human centrifuge). Distension of intracranial arteries is probably the mechanism of headaches due to nitrites, polycythaemia, atmospheric pressure changes, and, rather more commonly, to hunger, " hangover," fever, and infections. That migrainous headaches are also of this type is now well known. Attribution of headaches directly to constipation and to referred pain from structures below the level of the neck cannot, according to Wolff, stand critical examination. It may be good news to a few that vascular headaches, including some cases of migraine, can sometimes be abolished by standing on the head. One other common type of headache-usually nonpulsatile and often lasting unchanged for long periods -has been shown by means of records of action potentials to be associated with abnormal contraction of the skeletal muscles of the head and neck. Patients so affected may complain of a " tight band around the head," a fixed neck, and sore shoulders. The pain is apparen-tly partly due to sustained muscle contraction and partly to vasoconstriction, reduced blood flow, and ischaemia of muscle. Such headaches are particularly apt to be associated with a tense emotional state. Wolff's long interest in headaches and his great experience must lend weight to his general conclusions about their management. "More than 90% of people with headache have their headache as a result of vascular disturbances, sustained skeletal muscle contraction about the head, and vasomotor disturbances within the nose . . . Two people out of three with this vascular-muscle-tension headache combination can be greatly helped by any physician who is interested in human problems, and willing to spend a minimum of time with his patients in reviewing them with him." It is notable that one who has spent so much time on the study of headache by experimental methods should arrive at such very human conclusions. Perhaps a strictly scientific outlook and a human approach to clinical problems are not as incompatible as they are sometimes made to appear; and we may hope that more clinical investigators will be attracted to this kind of combined investigation. SYNDROME OF SARCOIDOSIS