Arnold P. Friedman

A classification of headache: Ad Hoc Committee on Classification of Headache

THE TERM HEADACHE commonly denotes head pain from brow level up. This outline defines headaches somewhat broadly; it covers both painful and nonpainful discomforts of the entire head, including the face and upper nucha. Since so much that a man describes as headache may be any abnormal head sensation, it is essential for proper treatment to determine whether the complaint is actually one of pain. A useful scheme for the classification of the varieties of headache is one based on pain mechauisms. The divisions rest on experimental and clinical data, together with reasonable inference; the story is far from complete. Yet the arrangement can serve as a framework for diagnostic criteria for the major clinical types of headache and by emphasis on basic mechanisms it offers a logical approach to the planning of therapeutic trials. For convenience, short and simple names are suggested for certain major entities and are indicated in boldface type. Essential in the study of headache in most instances is an appraisal of its close link to the patient’s situation, activities, and attitudes. Sometimes in obvious ways, more often in subtle ones, headache may be the principal manifestation of temporary or sustained dif6culties in life adjustment. These relationships are notably evident in Croups I through V.

Effect of serotonin in migraine patients

LITTLE is known of the factors that predispose to migraine or the biochemical events that initiate the disturbances characteristic of this condition. Earlier studies by Marcussen and Wolffl have shown that an initial phase of vasoconstriction is responsible for the prodroma1 symptoms, while the pain follows a marked distention of cranial vessels that are temporarily hypotonic. They also have presented certain evidence which presumably indicates that a pain threshold-lowering substance renders the distention of the large arteries painfu1.2 However, alteration in tone, lumen, and pain threshold of the arteries alone cannot explain the complex symptomatology of the migraine attack. Jimenez Diaz and associates3 have indicated that, during the migraine attack, there is a release of a substance more stable than acetylcholine, which they term S.A.C. acetylcholinelike substance. They also conclude that the normal choline acetylate system is different in these patients. Kunkle4 also relates this multisystem disturbance to a preponderance of parasympathetic nervous activity as manifested by a release of acetylcholine. An acetylcholine-like substance has been detected in cerebrospinal fluid during some intracranial vascular headaches of migraine type. These and other studies cast light on the nature of the pathophysiology of migraine, yet the primary event in the migraine attack remains undetermined. The effects of serotonin (5hydroxytryptamine-HT) suggest themselves as a means of gaining further understanding of migraine. The present study undertakes to determine the effects-clinically, physiologically, and biochemically-of serotonin and its precursor, 5-hydroxytryptophane (HTP), on patients with migraine. The physiologic significance of HT is implied by its potency in the central nervous system, gastrointestinal tract, cardiovascular system, and blood. The cardiovascular phenomena associated with HT excess are particularly interesting, in that its ability to produce vasoconstriction in some instances, and in some instances vasodilation, raises the possibility that this or a similar substance is the trigger, or part of the trigger mechanism, in patients with vascular headaches, that is, migraine. The nervous, cardiovascular, gastrointestinal, and renal effects of HT all have their counterparts in the migraine syndrome. It has been stated by other observers that exogenous HT can elicit an attack of migraine,5 and observations with a monoamine oxidase inhibitor have been interpreted to indicate that HT aggravates the symptoms of migraine.s WOW and associates7 have reported that, in 3 cases, temporal perivascular-injected HT induced effects similar to clinical migraine. This and other clinical studies suggest that a biochemical lesion of fundamental importance exists in migraine.

Migraine and Tension Headaches A Clinical Study of Two Thousand Cases

ALTHOUGH headache occurs in a wide variety of clinical conditions and is treated by a host of therapeutic procedures, the basic mechanism of most headaches is stimulation of pain sensitive structures in and around blood vessels. Among this group are headaches associated with hypertension, arteriosclerosis, infection, brain tumor, hematoma, allergy, and cranial trauma. These conditions are responsible for the symptom in only a small percentage of the cases who consult a physician because of headache. In the vast majority of the cases the symptoms either are due to migraine or are primarily associated with an emotional disturbance (tension headache). It is our purpose to consider only these two types and to summarize our experiences with 2,000 patients suffering from migraine or tension headaches. These patients were studied and treated during the past seven years.

Cutaneous blood flow in vascular headaches of the migraine type

AN INTIMATE CONNECTION between migrainous headaches and local vascular changes has long been suspected and several investigators have studied this relationship. Tunis and Wolffl recorded an increased amplitude of temporal arterial pulse waves during an attack and suggested that the pain is accompanied by dilation of the extracranial arteries. In other studies2 involving visualization of the conjunctival vessels, vasoconstriction frequently preceded and vasodilation invariably accompanied the headache. The action of certain vasoactive drugs in migrainous headaches further points to a close relationship between the state of the vessels and occurrence of pain. Thus, the administration of arterial vasoconstrictor agents such as ergotamine tartrate or norepinephrine has been shown to reduce both the amplitude of arterial pulsations and the headache.3 However, vasodilator agents do not produce vascular headaches as consistently as vasoconstrictor agents terminate the attack. Nitroglycerin, a vasodilator, may intensify a migraine episode and, in susceptible individuals, may induce In one study, reserpine in large doses regularly produced typical unilateral headache in migrainous subjects,5 but its site of action is presumably a central one. Because the interruption of migraine is closely related to changes in the local vessels, it was postulated that investigation of the local circulation might provide useful information concerning the mechanism of the attack. However, direct studies of the circulation through the tissues involved in cephalgic states have not been reported. This prompted Onel and associates6 in this laboratory to undertake the study of blood flow by a tissue clearance

TREATMENT OF HEADACHE

• Over 5,000 patients having the symptom of chronic headache were evaluated for their therapeutic response to many various drugs (e.g., analgesics, sedatives, stimulants, antihistaminics, vitamins, and hormones). At present, the best method of drug evaluation is the use of the double-blind technique, in which a placebo and two or more therapeutic agents are administered to a group of untrained subjects. The selection of suitable therapy for the treatment of headache depends on the correct diagnosis, which includes the associated emotional tension and anxiety.

Characteristics of tension headache: A profile of 1,420 cases

Abstract A multicenter clinical study provides a clear profile of the background and headache characteristics of l,420 patients with confirmed tension headache. The results verify characteristics that astute clinicians have noted in these patients for years. A guideline for differentiation of tension headache from migraine and other conditions is provided, and the essentials of management are discussed.

Craniovascular studies in headache; a report and analysis of pulse volume tracings.

THE RELATIONSHIP between cranial arterial circulation and headache has long been estab1ished.l In the past few years several papers have been published establishing a method of direct measurement of the volume changes occurring in various branches of the external carotid circulation.24 We have utilized these principles in our studies, and in addition have added a further method of photoelectrometric measurement of the volume changes occurring in the branches or tissue areas supplied by the external maxillary artery. The subjects on whom the studies have been performed have been patients with migraine, tension headache, or muscle contraction headache, and normal individuals who are not troubled with headache. The patients with migraine and tension headaches were studied in both the headache and headache-free phases. In order to differentiate between the two types, it is best to define clearly our criteria for the diagnosis of both migraine and tension headaches. characteristically paroxysmal, periodic, unilateral, and thr~bbing .~ The headache occurs against a background of relative well-being, is often preceded by visual or psychologic disturbances, and is usually associated with irritability. Physiologic mechanisms. The following physiologic changes occur in an attack of migraine:B An initial vasoconstriction of certain intracranial branches of the internal carotid artery produces visual and possibly other preheadache phenomena prior to the onset of headache. This prodromal period is followed by dilatation and distention of cranial arteries, primarily in the distribution of the external carotid artery. Stimulation of pain-sensitive nerves in and around the dilated vessels by the increased amplitude of pulsation is the presumed cause of the headache. Persistent dilatation results in a rigid, pipelike state of the vessels. The pain at this stage is a steady ache replacing the earlier throbbing pulsation type. During or following this, there is contraction of the neck muscles and “muscle contraction pain” develops. This spasm of the muscles is a reaction to the initial pain and may outlast it. The initial phase of the headMIGRAINE

Studies in the pharmacotherapy of headache.

MANY NEW DRUGS for the treatment of headache have become available to physicians in the last decade. Critical review of our material and the literature makes it apparent that the number and effectiveness are not closely related. In evaluating the treatment of headache by pharmacologic methods, a number of factors are difficult to control. The most annoying of all variables is that of the subjective report. Headache, as a symptom, is a subjective response, evident only to the individual experiencing it. The appraisal of therapy depends upon a cooperative statement made by the subject. What is headache and how much does it hurt? Moreover, there are 3 areas in which the effect of a drug must be considered: the original pain sensation and its mechanism; anxiety associated with the patient; and the secondary increase in dysfunction, including the additional pain sensation which accompanies the anxiety. Time, controlled studies, statistical methods, and clinical experience are essential for the appraisal of a drug. Pharmacologic studies are of value not only in appraising the effectiveness of the drug but also as diagnostic tests and in studying the mechanism of headache. The purpose of this communication is to review some of our accumulated experiences with pharmacologic agents in patients with muscle contraction and vascular headaches of the migraine type.

Further Observations in Craniovascular Studies

THE THEORY of vascular headache is predicated upon certain changes which occur in the external carotid circulation. These changes may involve alterations in the volume pulsations of part of the extracranial arterial system, as in migraine, or may involve alterations in the availability of oxygenated blood for the extracranial muscles, as in tension or muscular contraction headache. In the past decade considerable attention has been focused on the problem of measuring the volume and pressure changes of the external carotid arteries.lA Until recently, the only technics available for such study have been 1) intra-arterial puncture for the measurement of pressure changes, 2 ) use of glycerine pelottes for the measurement of volume changes, and 3) use of reflected or transilluminated light for the measurement of volume change^.^ Intra-arterial puncture of any of the branches of the external carotid artery is not a practical method for studying adequate numbers of patients. The glycerine pelotte and photoelectric technics are certainly more practical, but they are, unfortunately, endowed with too many variables. The best available method yet devised for studying the external carotid circulation is the use of displacement transducers. These transducers are microphones with subaudible frequency responses. They are extremely responsive to small displacements and frequencies encountered in various physiologic activities. Pulsations of very small vessels can be picked up and recorded easily. The type of transducer used has a definite electrical capacity which corresponds to the pressure with which the transducer is applied to the blood vessel under study. Thus, by measuring the capacity of the transducer, which can easily be accomplished by incorporating a calibrator in the circuit, the pressure of application of the transducer can be recorded with considerable accuracy (within 3 mm. of Hg). Using this technic, it is possible to perform repeat craniovascular studies on patients with considerable validity, for the pick-up can be reapplied to an artery with a standardized pressure as often as desired. The only source of error which remains is the positioning of the pick-up with respect to the artery. This variable can be minimized by measuring fixed points of

Treatment of Migraine

THE treatment of migraine has posed a problem for over two thousand years. Its severity and the tenacity of the symptoms have caused much concern to doctor and patient alike. If the physician who a...