HEADACHES

THE extensive studies of Graham and Wolff and their colleaguesled them to the conclusion that headachesare vascular in origin.' In 1927 Leake et alii postulatedthat headachescould arise from changesin volume or pressure of any of the three fluid or semi-fluid media within the rigid confinesof the skull.' They defined thesethree semiftuid media as the blood, the brain and the cerebro-spinal 'Ouid. It has generally been assumedthat the structures from which nociceptive impulses can arise within the cranial vault are the blood vessels,the dura, the tentorium cerebelli and the falx cerebri. Some recent work cannot escape the criticism that adequatesafeguardshave not been taken to ensure that the pain is really central and not a trigeminal diffusion from a peripheral focus. Sir Leonard Hill severalyearsago pointed out that air heated by a stove can bring about congestion of the highly vascularnasal mucousmembranesand that whatIs termed 11 headacheresults. Even experiencedclinicians have not infrequently discoveredin themselvesthat a so-calledheadache is really causedby an incipient boil or acne pustule in the region of the fifth nerve. Just as the neuralgiaof balf a century ago, often treatedby gelsemium,was really in many cases pain radiated from a carious tooth, so eertain of the headachesof today have a nasal, an ocular or an aural origin. Recently investigators in the Departmentsof Pharma.cology of the University of Chicagoand Wayne University Medical Schools have drawn attention to two types of true headachewhich they think should be separatedin any classificatory system from the "common headache"." One is the "relaxation headache"-"thetypical Sunday morning headacheof the businessman, the Monday head.ache of the clergy, the day-otr headacheof the nurse and the post-examinationheadacheof the student". It is worth noting in this connexion, as we learn from the brilliant biography written by his descendant,the British Prime Minister, that the famous Duke of Marlborough suffered .aeverely,after eachbattlewas over, from a headachewhich phlebotomyrelieved. TheseAmerican investigatorsbelieve that in the "relaxation headache"and also in the migraine headachethere is a diminution of the blood volume. The other type of headacheis the catreine-withdrawalheadache. Lack of the' usual morning coffee has led to, many Americans experiencing a headacherelieved quickly by administrationof caffeine or acetyl salicylic acid. In an .experimentalstudy caffeine was given each morning to a Dumber of medical studentsin gradually increasingdoses up to twelve grains. On withdrawal headachesresulted, lIIlany of them severewith senseof fullness or throbbing ;Ii the head. This type of headachethe authorsattribute to "increasein the effective arterial blood volume". The .critical reader of these articles, whilst admiring the ingenuity of the analysisand admitting most of the facts; will hesitate to accept without further confirmation the aimple dynamical explanations put forward. In the growing literature of headachecausationwidely different .conditionswill be found to be emphasizedas causativeor contrfbutory,such as diminishedcalcium in the blood, rise in the plasmaprotein, alteration of the blood phosphates and of blood potassium. Until someconsistencyis reached and until the site of the pain is proved beyond debate,the general practitioner will prefer to continue the treatment tJ,e has found effective even if this is labelled empirical by bis colleaguein the laboratory.