Page:The American Cyclopædia (1879) Volume III.djvu/206

 200 BRAIN (DISEASES) be unattended with any violent symptoms ref- erable to the head. A considerable haemor- rhage here, however, occasions insensibility or coma, which is developed suddenly or gradu- ally, according to the rapidity as well as the amount of the hcemorrhage. The patient may emerge from this coma, and if the hemorrhage recur, as is sometimes the case, the coma is again renewed. Usually, owing to the diffusion of the blood over the surface of the brain, there is not hemiplegia, as in cerebral hsemor- rhage. Death may be expected to take place if the amount of the htemorrhage be sufficient to occasion a prolonged or repeatedly recurring coma. A form of meningeal hemorrhage oc- curring independently of traumatic causes is known as haamatoma of the dura mater. In this form, the blood is under the dura mater, and is contained within oval fibrinous sacs sev- eral inches in diameter and three or four inches thick. These are generally found on the upper surface of both hemispheres of the brain. The fibrinous sacs are supposed to denote inflamma- tion. This affection occurs in children and in aged persons ; but it is rare, and not determi- nable with certainty during life. Sooner or later it ends fatally, after having induced diminished power of motion of the limbs on both sides and stupor, which at length eventuates in coma. IV. INFLAMMATORY AFFECTIONS. In the com- prehensive sense of the phrase " diseases of the brain," inflammatory affections may be seated in either the membranes or the cerebral sub- stance. Their primary seat is much oftener in the former than in the latter. Of the membranes investing the brain, the dura mater is very rare- ly inflamed. An inflammation seated in this, the outer of the cerebral membranes, or the meninges, is almost always limited to a circum- scribed space, and is produced either by an in- jury of the head (traumatic), or by an exten- sion of disease from a contiguous part of the skull. An idiopathic or spontaneous primary inflammation of this membrane perhaps never occurs, if the affection called hsematoma of the dura mater be excluded. The term cerebral meningitis denotes inflammation of the mem- branes or meninges of the brain ; but the term is considered as embracing only inflammatory affections seated in the pia mater and arach- noid membrane. Inflammation affects these two membranes conjointly ; that is, whether the point of departure be in the one or the other, both are involved. Cerebral meningitis is acute, subacute, or chronic. In addition, a variety of the disease is called tuberculous meningitis. The term simple meningitis is used to distinguish an ordinary inflammation from the variety called tuberculous. Exclusive of traumatic cases, that is, those in which the dis- ease is produced by injury from falls or blows, causes of simple acute meningitis are insolation, or exposure to great heat, and excessive indul- gence in alcoholic stimulants. These causes are chiefly operative when adults are affected with the disease. Acute inflammation from other causes than these, and from injuries of the head, occurs oftener in children than after adult age. In children it is sometimes developed in the course of scarlet fever, erysipelas, and measles. But simple acute meningitis, irrespective of traumatic cases, is extremely rare. The symp- toms of acute meningitis are at the beginning essentially the same as in active cerebral con- gestion ; and this, indeed, is the pathological condition. The prominent local symptoms are intense, diffused pain in the head, flushing of the face, notable intolerance of light and sounds, an increase of the sensibility of the surface of the body (hyperaesthesia), throbbing of the ar- teries of the neck and head, and delirium, which is often active or violent. Hallucinations, as well as delusions, enter into the delirium. With these local symptoms, there is symptomatic fever, as shown by frequency of the pulse, in- creased heat of the skin, and, more especially, augmented temperature of the body as denoted by the thermometer placed in the armpit. Con- vulsions sometimes occur. Other symptoms denoting constitutional disturbance are loss of appetite, often vomiting, constipation, disturbed rhythm of respiration, and more or less debil- ity, except when the patient is under the ex- citement of delirious volitions. These symp- toms belong to the first stage, or the stage of excitement, the duration of which varies from a few hours to several days. The symptoms which distinguish the second -stage are due mainly to compression of the brain by the in- flammatory products, lymph, serum, and pus, which are situated for the most part beneath the arachnoid membrane. These symptoms are somnolence ending in coma, paralysis of certain of the facial muscles, and sometimes of the muscles of the limbs, on one side, dilatation of the pupils, slowness and irregularity of the pulse, &c. These symptoms generally denote a fatal ending. This stage is distinguished as the stage of compression and of collapse. Sim- ple acute meningitis is always a disease involv- ing great danger to life. A very large propor- tion of cases end fatally. Life may be destroy- ed speedily, sometimes within a few hours. In most fatal cases the duration of the disease does not extend beyond a week. The measures of treatment which are appropriate to the first stage are: bloodletting by venesection and leeching, if there be no circumstances to centra- indicate the abstraction of blood ; cold applied to the head by means either of cloths wetted at short intervals in ice water, the cold douche, or the ice cap; and active purgation. As remedies which appear to diminish the blood within the skull, the bromides are to be recom- mended, clinical experience having shown their utility. In the second stage, the great object of treatment is to promote the absorption of the morbid products. Mercury and the iodide of potassium are prescribed for this object. Blisters may be employed for the same end. Alimentation, to an extent corresponding with the ability to take and digest nutritious food,