A system of practical medicine. By American authors. Vol. 5

by Unknown

The dilation of the pupil during an attack depends upon irritation of the cervical sympathetic ganglia. Other symptoms, such as the largely increased flow of saliva and the flow of tears or drying of the Schneiderian mucous membrane, indicate a morbid condition of the cervical sympathetic. The sensitiveness to pressure in the region of the upper cervical ganglia and over the spinous processes of the lower cervical and upper dorsal vertebræ, corresponding to the cilio-spinal region of the cord, confirms the idea of a morbid state of the cervical sympathetic.

In hemicrania angio-paralytica there is supposed to be a relaxed condition of the vessels of one side of the head. Here, instead of an irritation of the sympathetic, there is a paralytic condition, and we have the same results as are seen in animals when the cervical sympathetic is divided. There seem to be good grounds for holding this view when we consider the flushed face, contracted pupil, retraction of the eyeball, and occasional ptosis which accompany this form of headache. Possibly there may be a brief stage of spasm of the vessels preceding the relaxation which occurs in hemicrania angio-paralytica.

The slowing of the pulse during an attack of migraine is due probably to cerebral hyperæmia from relaxation of the vessels, or to the secondary anæmia and irritation of the medulla oblongata. This irritation of the medulla is also able to explain the other symptoms of vaso-motor disturbance which occur during an attack of migraine; for instance, the small and contracted radial artery, the extreme coldness of the hands and feet, and the suppression of perspiration over the whole body except perhaps on the affected side of the head. Following the stage of irritation of the medulla with contraction of the vessels comes one of exhaustion with relaxation of the vessels. This latter state may account for the profuse flow of saliva and the copious secretion of sweat and urine, as well as the increased secretion of bile and the condition of broncho-tracheal catarrh during the attack.

We now come to the question of the origin and seat of the pain in migraine. This question has involved a great deal of thought, and has been answered in various ways by different writers. E. du Bois-Raymond thought that the pain was due to tonic spasm of the muscular coats of the vessels, and that thereby the nerves in the sheaths of the vessels were pinched, as it were, and so caused pain. Moellendorff was of the opinion that the pain was due to dilatation of the vessels, and not to contraction; and this theory might explain the pain in the angio-paralytic form. There are many cases in which neither of these views is sufficient, for we have no reason to believe that a condition of either anæmia or hyperæmia is present.

Romberg believed that the pain was situated in the brain itself, and Eulenburg holds that the pain must be caused by alterations in the blood-supply, without regard to their origin, in the vessels of one side of the head. He thinks that the vessels may contract and dilate with suddenness, just as is often seen in some neuralgias, and thus intensely excite the nerves of sensation which accompany the vessels. The increase of pain upon stooping, straining, or coughing, and the influence upon it by compression of the carotids, seem to give force to this view. But are we not here confusing cause with effect? Are not these variations in the calibre of the vessels due to the irritation of the sensory and vaso-motor nerves, which are in a state of pain? No doubt increase in the blood-supply augments the pain, just as it does in an inflamed part when more blood goes to the part. Let a finger with felon hang down, or let a gouty foot rest upon the floor, what an intensity of pain follows!

Anstie very ably advocated the theory of migraine being a variety of trigeminal neuralgia in the ophthalmic division; and we incline strongly to his view. An attack of migraine often begins with pain distinctly located in the supraorbital nerve as the result of exposure to cold. Frequently it begins in the infraorbital nerve or in the branches of the inferior maxillary division of the fifth. The pain then spreads over one side of the head, both outside and inside, and goes through the recognized symptoms of migraine. In my own case I have often had an attack begin with sharp pain in the supraorbital notch in a spot which could be covered by the tip of the finger. The nerve has seemed swollen, and has been highly sensitive to pressure. Then have come pain extending over the entire side of the head, without its limits being distinctly definable, and the accompanying phenomena of lachrymation, excessive salivation, and copious flow of urine, winding up with vomiting or ineffectual nausea and retching.

Anstie brings forward as arguments to support his view the facts that the attacks of migraine often interchange with neuralgic seizures, and that a person who has been migraineuse in early life may in later years lose his hemicranial attacks, and have violent neuralgia in the ophthalmic division of the fifth nerve.

The true seat of the lesion, if we may so call it, upon which the exaggeration of pain-sense depends, is probably in the nerve-centre; that is, in that part of the trigeminal nucleus back to which the fibres go which are distributed to the painful areas. The pain is no doubt chiefly intracranial, and in those portions of the cerebral mass and meninges to which branches of the trigeminal are distributed. All of the divisions of the trigeminus send branches to the dura mater. Many nerves are found in the pia mater as plexuses around the vessels, some of which penetrate into the centre of the brain. Most of these nerves come from branches of the trigeminus.

TREATMENT.—The treatment of migraine must be directed to the palliation of the attacks and to their prevention. So little is known of the direct cause of the disease that it is difficult to lay out any distinct course to be followed. Many cases, however, which seem to depend upon a run-down state of the patient are vastly improved by a course of tonics and building up. I have often seen anæmic and feeble women whose attacks were frequent become exempt for a long period by simply taking iron, quinine, and strychnia, and taking an increased amount of nourishment. The rest-treatment of Weir Mitchell is particularly applicable to these cases. In persons whose digestion is bad, and who suffer from constipation, much can be done by relieving these conditions. Some cases which are due to uterine disturbances are benefited by treatment directed to the womb. There are many cases, however, in which no cause is apparent. The patient is well nourished, his eyes are good, he undergoes no strain mentally, morally, or physically, and yet the attacks of migraine come with tolerable regularity. In these persons change of climate sometimes works marvellously beneficial results. I saw last year a young lady who suffered from terrific headaches which sometimes lasted for days. No plan of treatment or regimen seemed to exert the slightest influence upon the attacks, and yet on going to the far West for the summer she remained without an attack during the whole time she was there. In some individuals all forms of treatment may be tried in vain. Anti-periodics have been tested, but with doubtful benefit. Cannabis indica is probably the most potent remedy which is at our command. Its effects are most decided, and many cases of severe hemicrania have been cured by this means alone. It must be given for a long time, and in some instances it is necessary to give gradually-increasing doses up to the physiological effects. The drug must be of good quality, otherwise we need expect no good from it. Indian hemp is well known to be variable in strength, and the best form in which to use it is a fluid extract made by some reliable chemist. Arsenic, phosphorus, and strychnia do not seem to do as much good as in other neuralgias, except so far as they build up the general health.