Blood may be effused upon the surface of the brain in the so-called cavity of the arachnoid—that is, outside of the pia mater—or in the meshes of this membrane, following its course along the sulci. This also is not infrequently the result of violence either with or without fracture of the bone. Its source is likely to be found in the veins which empty into the longitudinal sinus from the surface of the brain. Rupture of a lateral sinus from a not very severe blow has been the source of large and fatal hemorrhage.1Blows upon the head, with or without fracture of the cranial bones, are likely to cause rupture of the cerebral substance with hemorrhage, and this may find its way to the outside and cover more or less of the surface. Such injuries to the brain, it is important to note, do not necessarily correspond immediately to the place of the blow or to the external ecchymoses. Meningeal hemorrhage in this region may, however, be observed when no injury has been received, or at least when there is neither history nor external traces of any.
1Cincinnati Clinic, p. 135, 1874.
The conditions under which it occurs may not vary greatly from those of the more ordinary intracerebral effusion. In two instances under the observation of the writer the source of hemorrhage has been a vessel of small, but not the smallest, calibre (artery), situated near the fissure of Sylvius, in the lower parietal or temporo-occipital lobe. In children meningeal hemorrhage is, with only a few exceptions, the usual lesion of apoplexy. The blood is usually dark and coagulated in recent cases. Blood found under the membranes where no fracture has taken place is, however, more likely to have been derived from the brain-substance and to form part of a cerebral hemorrhage.
Hemorrhagic pachymeningitis, indicated by a layer of fibrin included between the dura on the one hand and a false membrane on the other, is met with in connection with meningeal and cerebral hemorrhages. It is supposed to depend on a small and thin hemorrhage upon the surface of the brain, which forms, by its irritant action, a false membrane about itself. It is found usually over the vertex.
Hemorrhage into the ventricles is nearly always the consequence of a hemorrhage in the brain-substance breaking through, although it may in rare cases originate in the vessels of the choroid plexus, velum interpositum, or meninges. Its source, however, is sometimes so near the surface as to cause but little laceration of the cerebral tissue. The blood breaking into any one of the ventricles may be found in one or all of them (except the fifth), and form quite an accurate cast of their shape.
The most common form of intracranial hemorrhage, however, which most nearly concerns us here, and which is generally meant when sanguineous apoplexy is spoken of, has its principal seat in the brain itself, which is, of course, more or less lacerated. Such hemorrhages may vary greatly in size, from a mere red point (punctate or capillary), of which many may be present at once, to one of many ounces, filling a large cavity of nearly the length of one hemisphere, and pushing the torn and compressed brain-substance before it in every direction. The amount of laceration produced of course varies greatly; sometimes it seems as if nothing more than a pushing aside of fibres without rupture had taken place, while at others large masses of tissue are torn away and mixed up with the blood into a pulp.
In a recent hemorrhage the clot itself, speaking of those of a size above the capillary, is usually homogeneous, the brain-substance surrounding it ragged, œdematous, yellowish or red, and frequently containing many minute secondary hemorrhages. The rest of the brain is frequently found anæmic from pressure, the convolutions flattened, the surface dry, and the section exhibiting a diminished quantity of blood. In older cases, however, and probably also in some where atrophy, senile or otherwise, has preceded the hemorrhage, this condition is not found, and we may have the convolutions shrunken and the meshes of the pia containing an excess of serum.
If death does not take place speedily, the clot undergoes degenerative changes. Its color becomes somewhat lighter, chocolate color, reddish-yellow, or yellowish-red. A portion is absorbed, and after a time the cerebral substance in the neighborhood forms about it a wall of some density, so that finally nothing is left but a cyst with fluid or semifluid contents, and often remains of connective tissue. Sometimes the absorption of a clot of moderate size is so complete that only a firm mass of a reddish or yellowish-brown color marks the seat of an old hemorrhage. The brain-substance in the neighborhood may be more or less atrophied, and a distinct depression may be noted over the position. The microscope shows in a fresh hemorrhage only broken-down nerve-tissue and blood and vessels more or less degenerated. In an older one the blood-corpuscles have disappeared, but masses of pigment of a dark yellow or a brownish-red remain to show the former presence of blood. This pigment occurs in the form of rounded granules or of small rhombic crystals, and has received the name of hæmatoidin. The light-yellow masses often found along the course of the cerebral vessels are not evidence of hemorrhage, but of congestion merely. The so-called inflammation or granulation corpuscles, which are simply the fattily degenerated cells of the organ in which they are found, and which usually possess no distinctive form, being simply round masses of fat-drops, are often met with in the brain in hemorrhage or softening. It is sometimes perfectly evident, however, from their form, triangular or pyramidal, that they are degenerated nerve-cells. The blood-vessels, those just above the size of capillaries, are usually in a condition of fatty degeneration, masses of dark granules occupying more or less densely the line of their walls. A mere deposit of fatty granules inside the perivascular sheath, but outside of and not involving the walls of the arteries, may present the appearance of a degeneration of the walls themselves. This condition may be a consequence of any lesion involving degeneration of brain-tissue, and in no way a cause.
The intermediate stages of transformation in a hemorrhage are less frequently found than the recent or old ones, since the patient, if he does not die within a few days, is likely to live for some weeks or months.
The changes taking place in the clot itself within the first few days are not very marked, but the walls of the cavity may become softer and more deeply colored, at first red and afterward yellow. Blood-crystals have been detected on the seventeenth day (Virchow). The following descriptions have been given of clots of different ages: Eleven days—reddish-yellow softening clot, with brain-tissue stained for half an inch in depth, and brain rather hard in vicinity. Eighteen days—cavity with itsedges anteriorly and superiorly sharply defined, with the edges posteriorly ragged and yellowish, filled with a tolerably firm brick-red mass adherent to surrounding brain, and showing in the centre a softened clot about the size of a pea. Twenty-eight to thirty-five days—soft, brownish, and semifluid. Forty-one days—spot of softening filled with brownish material. One hundred days—somewhat darker, and a little more distinctly marked from surrounding tissues; by microscope granular corpuscles, groups of fatty granules along the swollen vessels, granules of pigment. Eighty-three years—old hemorrhagic focus in right optic thalamus, color yellowish, and areolar structure.
The thirtieth day is given as about the time at which the walls of the cyst become more firm and distinct. The following statement is prepared from a considerable number of cases given by Durand-Fardel: From four to six weeks, the clot is dark-colored, from black to ochrey or reddish-yellow. It varies in firmness. The capsule is tolerably firm. From two to four months, it seems to be generally softer, pultaceous, grumous, or the clot still remaining swimming in serum; in some cases lighter in color. In six months it has lost more in color, and the cavity may be smaller. In a year there is still considerable color left. In a few cases after some years the blood has been found in the form of a dried mass, not changed or darker in color.
Hemorrhages of several months' standing may be indicated either by a brownish-red patch somewhat firmer in texture than the surrounding brain-substance, or by a cavity with firm walls, which often has strings and septa of connective tissue running across it, so as to convert it into a kind of spongy mass filled with brownish fluid.
The most important changes which are found in most if not all cases of ordinary hemorrhages (i.e.such as do not depend upon violence or cachexia) are those of the blood-vessels. They are not, however, visible in the ordinary inspection of the brain at an autopsy, but require to be carefully sought for, either with the microscope or a somewhat tedious process of washing. For this reason there are no trustworthy statistics of large numbers to determine in how large a proportion of all the cases alterations in the blood-vessels are to be found, and in what form. There can be but little doubt, however, that those cases in which no form of arterial disease is present (if, with the reservation just noted as to violence or cachexia, such exist) are to be looked upon as rare exceptions.
The presence of miliary aneurisms in the brain had been noted in some cases, and even in cerebral hemorrhage, without the great importance of the observation having been perceived; but the extended and careful observations of Charcot and Bouchard first showed how extremely common their presence is, while in many instances they were found actually ruptured. These aneurisms are present in the largest numbers in the regions of the brain where hemorrhage is most frequent, and at the age when death from apoplexy is most likely to occur. They have been found at the age of twenty, but very rarely at early ages, while after forty they are not uncommon. It is of course not always that they have gone on to rupture, but may occasionally be found where no hemorrhages have taken place. It is not going far, however, to infer that in such cases the hemorrhage was not very distant.
These aneurisms are dependent upon a periarteritis which is diffusedmore or less widely over the cerebral arteries, but not over those of the rest of the body. The larger arteries get a thin and shining appearance, compared by Charcot and Bouchard to the skin of an onion, while the smaller ones present besides distinct aneurisms, bulgings and irregularities of outline. This condition may be—and, as would be at once suggested from the age at which both lesions are met with, is—very likely to be associated with atheroma, but it is not the same thing, since the development of the aneurisms depends upon a periarteritis, and that of atheroma upon an endarteritis. It may be remarked, also, that atheroma usually does not affect the very small arteries which bear the aneurisms and give rise to the hemorrhage.
These aneurisms are visible to the naked eye, being from two-tenths to one millimeter, or a little more, in diameter, while the artery to which they are attached can be seen by the naked eye or with a lens magnifying two or three diameters. They may be strung along a small artery like beads or be found in groups like a bunch of grapes. Charcot and Bouchard found them in every case of cerebral hemorrhage which they examined, and, although the possibility of other sources was admitted, concluded that in by far the greater number of cases, excluding those dependent upon traumatism or hemorrhagic diseases, the blood effused in the brain has its origin in one of these aneurisms. The presence of these aneurisms has been abundantly established by other observers, and the fact that they are not usually demonstrated proves nothing except the amount of care and time necessary to find them. One does, however, find occasionally noted that they were sought for and not found. The statements of Charcot and Bouchard relate, so far as their own observations are concerned, and as they themselves remark, chiefly to aged persons, but in their first series of 66 cases there is found 1 of twenty and 1 of forty years of age. The patient of twenty was a semi-imbecile and a drunkard. Extensive cerebral hemorrhage, with atheroma, in the circle of Willis has been found in an apparently healthy and well-nourished boy of fifteen.2
2Baker,Annals of Anat. and Surg. Soc. Brooklyn, 1879, p. 40.
Larger aneurisms, often multiple, are not very infrequent upon the arteries at the base of the brain. They may before their rupture give rise to symptoms of pressure like any other tumor, and may also be the source of hemorrhage, which is usually meningeal. They are not infrequently symmetrical, and a place of election is one of the early bifurcations of the middle cerebral.
Coats3states that aneurism of the larger arteries is the most frequent source of hemorrhage in persons under fifty. They may be due to embolism, producing, when the occlusion is not complete, mechanical injury to the walls of the vessels by the constant hammering upon them of the embolus under the impulse of the blood. If this etiology is a common one, it accounts for the frequent situation of these aneurisms in the middle cerebral arteries.
3Glasgow Med. Journ., 1882, xvii. 109.
Small vessels in a condition of fatty degeneration are often found in the neighborhood of a cerebral hemorrhage. In some cases, undoubtedly, the degeneration is a consequence of the injury to which the cerebral substance has been subjected, but they have also been found too soonafter the hemorrhage for this explanation to hold; and in cases where no aneurisms are present the older supposition, that hemorrhage results from this kind of degeneration, seems to have a certain foundation, even if only in a minimum of cases.
In several cases of cerebral hemorrhage in purpura, where the general character of the disease was shown by hemorrhages in other organs, fatty degeneration of the cerebral vessels has been found, together with extensive steatosis of the liver, kidneys, muscles, and heart.4In a cerebral hemorrhage found in the brain of a girl of eleven the walls of the vessels were dotted with fat-globules and dark granules, and several of them studded with round and oval nuclei closely resembling the nuclei (small cells?) commonly found in tubercle. There was no trace of tubercle in any part of the body.5
4Gazette hébdomadaire, May 12, 1876, p. 288.
5Trans. Path. Soc., Cayley.
There is no possible means of determining in which way any given bleeding has arisen, except a very minute search, and this may fail to show the actual point of rupture. It seems highly probable, from the connection of some cases of hemorrhage with valvular disease of the heart, that embolism may give rise to effusions of blood, especially capillary and multiple ones. In such cases the emboli may be deposited in arteries far too small to be obvious in the ordinary process of dissection. (See Capillary Embolism.)
Hemorrhage arises in some rare cases from the backing up of blood in the veins when they are obstructed by thrombosis. A case has been described where meningeal and ventricular hemorrhage resulted from a rupture of the straight sinus at its juncture with the torcular Herophili.6
6Mullar,Lancet, 1849, i. 607.
In many diseases like purpura, idiopathic anæmia, and leucocythæmia many hemorrhages may take place in the brain as well as elsewhere throughout the body. Their importance under these circumstances is usually not great.
The usual localities of cerebral hemorrhage are stated with much minuteness in the following table from Durand-Fardel, which, although not very recent (1854), is not the less accurate on that account. No subsequent statistics have essentially altered its most important conclusions. In 139 cases the hemorrhage was situated in the hemispheres 119 times; in the protuberance (pons), 21; in the cerebellum, 13; total, 153.
I have placed beside these a small number of cases from the records of the Boston City Hospital and my own practice, and, to avoid the multiplication of headings, have entered some multiple hemorrhages under two or more heads, so that from the whole number of cases (46) there are 81 entries:
It would not have been very difficult to increase these figures from the large number of recorded cases, but there is nothing in later statistics to invalidate the statement that the corpus striatum, including both its nuclei, but especially the nucleus lentiformis, the optic thalamus, and the white substance in their neighborhood, are the portions of the brain by far the most frequently affected by hemorrhage, and especially by hemorrhages of considerable size.
There is no essential difference in the frequency of hemorrhage on the two sides. It may occur on both sides at once. Hughlings-Jackson says that he saw a patient who escaped with life from the effects of a clot which had paralyzed both sides of the face as well as all four limbs. Charcot and Bouchard give the following localities as containing in decreasing frequency the miliary aneurisms: optic thalami, corpora striata, the convolutions, the protuberance, the cerebellum, the centrum ovale, the middle peduncles of the cerebellum, the cerebral peduncles, and the bulb. The close correspondence of this list with the table of Durand-Fardel is in itself a strong argument in favor of the importance of the miliary aneurisms as the principal factors in determining cerebral hemorrhage.
The arteries supplying the nucleus lenticularis and external capsule are small branches arising chiefly from the middle cerebral a short distance from its origin, with some assistance from the anterior and posterior cerebral. One of the larger of them runs along the outer side of the nucleus lenticularis where it is covered by the external capsule—a disposition which may have something to do with the occurrence of the larger hemorrhages so likely to take place just outside this nucleus and into the substance of the hemispheres.
The arteries of the optic thalamus arise from the posterior communicating or the posterior cerebral. Why these two groups should furnish, as they do, so large a part of cerebral hemorrhages it is impossible to state, unless it be that from their origin so near to the larger trunks before their division they are exposed to more pressure, and hence a greater tendency to form aneurisms. The functional activity of these regions is another possible reason. The largest hemorrhages also seem to spring from these sources, and if a table of large effusions were compiledit would probably show a greater predilection for this locality than even the general one given above, which includes those of all sizes.7
7A very careful study of the form and size of foci of bleeding arising from the various nutrient arteries of the brain will be found in the well-known elaborate papers of Duret (Archives de Physiologie, 1874).
Before proceeding to a minute account of the symptoms accompanying cerebral hemorrhage, a consideration of the relation between extensive lesions and the most fully-developed clinical phenomena will be of value—in other words, the pathology of hemorrhagic or sanguineous apoplexy. This will naturally demand a reference to the cases where the same symptoms are present with a different lesion.
The most marked symptom, one which is essential to the definition of apoplexy, is the sudden, or more frequently rapid, loss of consciousness, and next, in a great proportion of cases, a unilateral paralysis or paresis. The latter, in many cases, finds a sufficient explanation in the rupture of fibres connecting the motor centres in the brain with the spinal cord; but this does not cover all cases, for it is well known that we may have paralysis without any laceration. In fact, in many cases paralysis may disappear so rapidly as to put aside at once any such explanation. Sufficient pressure upon contracting fibres is entirely competent to arrest their conductivity, and this pressure may be diffused over a considerably wider area than that where total destruction of tissue has taken place. Meningeal hemorrhage, where, of course, no laceration takes place, may be attended by a well-marked hemiplegia when the effusion is wholly or chiefly on one side.
The writer recalls a case of a man, of whose history little or nothing was known, found unconscious with a very distinct difference in the amount of motion to be provoked by irritation of the two sides. The diagnosis naturally inclined to the more common causes of hemiplegia, but the autopsy showed a purulent meningitis of the vertex, with a layer of pus considerably thicker on the side opposed to the paralysis.
A very similar statement may be made in regard to the symptom of unconsciousness, which seldom occurs more rapidly and completely than in cases of meningeal hemorrhage (not from injury), where, of course, there is no question of laceration.
F. Pagenstecher8succeeded in producing phenomena closely allied to apoplexy by injecting at a known pressure, between the skull and dura mater in dogs, masses of melted wax and tallow. In the first group of cases the result was somnolence, great depression of the psychical capacity, and general muscular weakness. The second group showed, besides the condition of sopor, unilateral paralysis; and the third contained cases in a part of which death followed in a few hours after the setting in of coma, and in another part partial recovery took place after scooping out the waxy mass. The symptoms in these cases are referred to the pressure upon the vessels; and it is stated that in order to destroy life the pressure had to be equal to that of the blood. Convulsions were present in some cases where the pressure was not steady. The temperature showed a notable peculiarity in that, after the initial fall, in which it resembles the course in human apoplexy, it kept on falling in the fatal cases, instead of rapidly rising, as in man. After injection into the brain of animalsof sufficient quantities of water to produce great tension of the occipito-atlantoid membrane, Duret9found the respiration to cease and the heart to be slowed. On tearing the membrane so as to allow the water to escape, respiration began again, and the animals gradually recovered consciousness. Similar effects could, however, be produced by blows on the head.
8Centralblatt f. d. Med. Wiss., 1871, p. 706.
9Centralblatt f. d. Med. Wiss., 1878, p. 454.
Several cases are reported by P. R. Hoy10where pressure upon the brain produced an arrest of function, which was resumed when the pressure was removed. In the first of these a piece of bone had been removed, but the dura was intact. If the patient were asked a question and the finger immediately pressed upon the dura, no answer was made, but as soon as the finger was removed the reply came. In two other cases, which are not without their parallels, the patients resumed after trephining the mental attitude in which they had been surprised by the injury—in one case hours, and in the other years, before.
10Journ. Nerv. and Ment. Dis., vol. iv. p. 288.
The natural generalization to be made from these cases and experiments is, that pressure upon the brain-tissue suspends, for the time, its function; but when we find exactly the same symptoms arising from either sudden or gradual occlusion of the vessels where we can hardly imagine increased pressure to exist, except perhaps over a very small area of collateral hyperæmia, we must go a step farther for a common factor; and it seems possible to find one which will not only explain the several conditions spoken of, but also others which closely resemble them. Simple anæmia will cover the cases of hemorrhage and embolism, but certainly not narcotic poisoning and certain other conditions where characteristic apoplectic symptoms exist without discoverable lesion. If, however, we say that a deprivation of a considerable portion of gray matter of its due supply of arterialized and healthy blood suspends for a time its functional activity, we can explain the similarity of results arising from very different causes.
In a case of cerebral hemorrhage of considerable size the pressure is distributed over a space much exceeding the area of the clot itself, and renders a large part of at least one hemisphere anæmic. If the blood finds its way into the ventricles, the conditions are most favorable for compressing nearly the whole brain. The anæmic appearance of the cerebral surface is often remarked at autopsies.
When an embolus lodges in an artery and produces complete occlusion, the portion of brain supplied thereby becomes at once entirely anæmic, since the arteries on the surface have so slight anastomoses that they are entirely unable to supply the deficiency, except to a slight extent around the edges of the vascular territory involved. The anæmia, however, does not extend beyond the territory originally affected, and consequently we may have extensive paralysis from embolism without a marked apoplectic attack. In extreme congestion of the brain the reverse may seem to be the case.
In reality, the hindrance to the proper functions is nearly the same, since blood which is not duly renovated and contains the products of metamorphosis of tissue in excess is worth as little for healthy nutrition as no blood at all. There is no reason to suppose that blood incirculation, no matter in how great quantity, gives rise to unconsciousness. It may cause over-action or disordered action, as in mania, but not arrest of action.
The narcotic poisons also deprive the nerve-tissue of its healthy food; whether by interference with oxygenation and depuration, or by a direct action of the substance itself on the nerve-cells, it is not easy to say. The fact that the completeness and duration of the unconsciousness are not in proportion to the paralysis or anæsthesia shows that they are to some extent independent of each other; and, although it is possible to locate with some precision the lesion which abolishes motor power and conscious sensation, yet we cannot say how much or what part of the brain must be deprived of its function in order to produce that cutting off of all conscious relation with the external world and reduction of a feeling, thinking, remembering, and acting organism to the level of a mere automatic breathing-machine, which we designate as loss of consciousness.
In fact, in the present state of our knowledge as to what consciousness is, any speculation as to its seat would be a waste of time, and we must content ourselves with recognizing that experience seems to show that a large part, rather than any particular part of the brain, must be involved, not necessarily in the primary lesion, but in the resulting pressure or anæmia.
Another theory of unconsciousness is simply that it is due to shock—that the sudden irruption of blood acts like a blow, as it were, and abolishes for a time the function of the nervous structure. This is substituting something indefinite for something comparatively definite; and it is certainly not true that the more sudden the shock the more complete the unconsciousness. It may come on after the paralysis is apparent, and in fact is more commonly gradual than sudden in its onset. The classical instantaneous shock is the rare exception. In the celebrated case where a tamping-iron was driven completely through a man's skull and brain, he himself was able to give a clear description of the accident to the surgeon who first attended him. Several other instances of severe and sudden injury to the brain without loss of consciousness have been recorded.
ETIOLOGY.—As regards the greater number of cases and the most common pathology, the existence of so specific and peculiar lesion as aneurism enables us to distinguish between predisposing and exciting causes, or, in other words, the conditions which lead to the localized periarteritis with its resulting aneurisms and those which cause their rupture. Unfortunately, the aneurisms are not usually looked for, and in the collection of statistics we are obliged to group together cases the pathology of which is not always the same, and which are usually collected under the name of apoplexy.
Age, however, is well known, both on clinical and anatomical grounds, to be the most important factor. Among the predisposing causes of apoplexy, all statistics, both of recent and older date, agree in assigning the period of life beyond forty-five or fifty as that in which the liability to apoplexy is greatly increased. There is no age, however, below this, even to infancy, in which true cerebral hemorrhage may not occur, although the intracranial hemorrhage of children is more usuallymeningeal. It is probable, however, that in many of these the rupture of the vessel does not depend upon a previous aneurism, but on other lesions. The youngest case in which aneurisms were found by Charcot and Bouchard was twenty.
If we speak of cerebral hemorrhage in general, without reference to the presence of aneurisms, as we unfortunately are obliged to do in the great majority of cases, we may often go much below this point. In youth and childhood, however, it is possible, and often almost proved, that other conditions must have been of greater importance in determining the hemorrhage than aneurism.
In our own small series we find cases of eighteen, twenty-three, twenty-five, twenty-six, twenty-seven years of age, and quite a number from thirty to forty-five. A little further examination shows many of them not to have been of the ordinary kind; thus the patient of eighteen had valvular disease of the heart and advanced parenchymatous nephritis; the one of twenty was, so far as could be seen, typical, but no search was made for aneurisms; that of twenty-five had many small hemorrhages and was a marked case of idiopathic anæmia; that of twenty-six had valvular disease of the heart, an embolus in the middle cerebral artery, which was not in the immediate neighborhood of any hemorrhage, several old hemorrhages, and hemorrhagic infarction in other organs. The case aged twenty-seven had a very large clot in one hemisphere and advanced interstitial nephritis.
Cayley11describes the case of a girl of eleven with a large cavity in the left middle cerebral lobe, where nothing was discovered abnormal upon the left middle cerebral artery, but when the cerebral matter was washed away with a stream of water, the walls of the vessels were found to be dotted with oil-globules, and in several places studded with round and oval nuclei. This was before miliary aneurisms were known, but the process of preparation was exactly suited to bring them to light had they been present, and they could hardly have escaped observation and mention. Other cases of boys have been reported where the hemorrhage was of the typical kind.
11Trans. Path. Soc., vol. xx.
Meigs and Pepper speak of nine cases of hemorrhage into the substance of the brain in children, but give none of their own. Of the two cases mentioned by West as coming within his own observation, in one the source of the blood was in the cerebral veins obstructed by the formation of clots in the longitudinal sinus.
C. W. Dulles12describes a case occurring in his own practice in a child of six months, where a considerable amount of blood was found in the lateral, third, and fourth ventricles. Nothing is said of aneurisms in particular, but the brain was carefully examined without the source of the hemorrhage being found, although it seemed to be in some of the vessels of the velum interpositum. Dulles mentions further a case reported in the books of the Philadelphia Hospital by Joseph Berens, where in the brain of a child ten days old there were found, besides a large meningeal hemorrhage, many points of subarachnoid extravasation, a clot filling all the ventricles, and a clot the size of a pea in the anterior portion of both corpora striata. In addition to these there were scattered points of hemorrhage throughout the brain-substance.
12Philada. Med. Times, vol. vi. p. 507.
Cerebellar hemorrhage seems to show a certain preference for younger ages than the more usual forms. In a list of 25 cases from various sources I find the ages given thirty-two, twenty, nineteen, sixteen, thirteen and a half, eight. In the seven cases detailed by Hillairet there were two aged fifteen and twenty-six respectively.
These exceptions, however, do not invalidate the rule that cerebral hemorrhage of the ordinary type is pre-eminently a disease of later middle or advanced life.
The male sex is more liable than the female. Durand-Fardel gives 54 cases of men, 37 of women (old persons); our own list, 31 men, 15 women. Falret, cited by Rochoux and Durand-Fardel, gives 1670 cases of apoplexy among men and 627 among women. This, however, is only a rough approximation as regards cerebral hemorrhage, as it undoubtedly includes many cases not dependent upon this lesion. The same remark applies to Lidell's statement that there died in New York during three years, of apoplexy, 598 males and 440 females. This moderate predominance is ascribable to greater muscular effort, and probably also to the greater prevalence of alcoholic intoxication. Greenhow, in a Parliamentary report,13states that in England and Wales the number of deaths from apoplexy in 100,000 of population is 46 males to 44 females. From paralysis the figures are 42 and 44, so that the total from the diseases registered under these two heads is alike for the two sexes—viz. 88 to 88. In London alone the discrepancy is a little greater on the male side—108 to 101; but in certain districts of England the excess is on the other side. Race is of little influence. High altitudes (7000 feet) favor the prevalence of apoplexy in the population,14as in Peru and Mexico. Warm climates are somewhat, but less markedly, opposed to it.
13Results of Inquiries into Different Proportions of Deaths, etc.
14Hirsch,Handbuch der Hist. Geoqr. Pathologie, vol. ii.
Heredity seems to play an important part in the same sense as in tuberculosis; that is, in the establishment of a tendency, which of course means, anatomically speaking, periarteritis. Many deaths from cerebral hemorrhage may sometimes be found among the members of a single family. Dieulafoy has been able to trace this disposition through several generations. Among several instances, Mme. G—— died in three hours of paraplegia with loss of consciousness. Her mother had hemiplegia at the age of fifty-two, and two uncles and an aunt were also paralyzed at ages not stated. A commercial traveller, aged thirty-nine, was in the hospital with left hemiplegia, second attack; his mother, aged sixty-six, had an attack a few weeks before, and his grandmother died at seventy-five of fulminating apoplexy. A woman aged forty-six was hemiplegic for two months. Her mother, her maternal aunt, and uncle are all hemiplegic, and her son had a left hemiplegia at the age of seventeen. According to the cases of Dieulafoy, it is especially through the female side that the hemorrhagic disease is transmitted. Of course, the tendency may remain, and usually does so, latent until the age at which in the average of cases it becomes manifest by an apoplectic or paralytic attack; but the last two series given above show that it may develop at an earlier period of life in the younger than in the older generation.
Alcohol is universally stated by authorities to be one of the most potent factors in different races in establishing the hemorrhagic tendency:but it is not easy to get exact facts on this point, as so large a share of hospital patients are more or less alcoholic, and in private practice observations of this kind accumulate so slowly as not to be readily available. The greater frequency of this affection among the male sex may point in this direction. Two of the usual effects produced by the long-continued use of alcoholic drinks in excess probably combine to produce this result: first, the degeneration of tissues and tendency to low forms of inflammation of the tissues in general and arteries in particular; and secondly, the repeated dilatations of vessels under its paralyzing influence on the vaso-motor nerves, resulting in chronic congestion. This preparatory influence is distinct from the effect an occasional debauch may have in precipitating the attack.
Another highly important cause of cerebral hemorrhage is Bright's disease of the kidneys, in the form known as chronic interstitial nephritis, contracted, granular, cirrhotic, or atrophied kidney; or, as it would be perhaps more correct to say, cerebral hemorrhage is one of the results of the arterial lesion which almost invariably accompanies interstitial nephritis. As to the supposed or possible identity or relation of the arterio-capillary fibrosis of Gull and Sutton with the periarteritis of Charcot and Bouchard, the writer does not feel competent to express an opinion.
The connection between cerebral hemorrhage and hypertrophy of the heart was noticed and commented on long before it was known that the great majority of cases of hypertrophy, where no lesion of valves or of the aorta was present, were really cases of Bright's disease. The influence which might be exerted by the high arterial tension in the rupture of an aneurism is obvious enough theoretically, but it is far from certain that the effect of the renal disease, or rather the common cause of renal and cerebral disease, is not a more subtile one than this, and prepares the way for, as well as hastens along, the impending catastrophe.
This result, however, is not an extremely common one. Among 43 fatal cases of interstitial nephritis, well-marked cerebral hemorrhage was found in 4; in another, cysts and brownish indurations of small size were found which might have been partly the results of embolism. This patient had had a distinct paralytic attack. In a fifth the symptoms pointed unequivocally to a large rapid hemorrhage, although it was not demonstrated by an autopsy.
Looking at it from the other side, it was found that (in another series) of 48 cases of cerebral hemorrhage with autopsy, contracted kidneys were present in 17; and the writer is of the opinion, although he has not at his command a sufficient number of facts to make such an opinion conclusive, that if a series of cases were taken of persons under forty or fifty, excluding those where a hemorrhagic disease or a valvular disease of the heart might be present, the proportion of interstitial nephritis to cerebral hemorrhage would be greatly increased; and especially so if large hemorrhages into the great ganglia or the interior of the cerebral lobes were alone considered.
The so-called apoplectic constitution should be mentioned here; that is, the stout, thick-set build with short neck and florid complexion. The popular notions as to the peculiar dangers of this condition seem to have arisen rather from suppositions as to what might be supposed to take place, from inferring a similar state of things to exist in the brain towhat exists in the countenance, than from any observation as to what has actually occurred. Cerebral hemorrhage may take place with any sort of complexion or any figure, and there is no sufficient evidence that persons of the physique above described are specially liable to it. Many recent writers distinctly deny any such connection.
Intellectual pursuits have been considered a disposing cause—a theory which it would be difficult to substantiate. It is not, of course, the quality of the work, but its relation to the capacity of the individual brain, which makes any amount of thought a special strain. The cases of Dieulafoy, in which the hereditary tendency was so strongly marked, were mostly hospital cases, among which class the so-called intellectual occupations do not specially preponderate. A life of constant cerebral excitement, like that of a speculator or stockbroker, certainly seems more likely to give rise to overstrain of the vessels than the more quiet and regular, but certainly more intellectual, labor of the professional or literary man.
Thackrah15speaks of affections of the head as frequent among professional men, but does not advert to cerebral hemorrhage in particular. He evidently considers a want of sufficient exercise in the open air a far more potent factor than mental excitement.
15Health and Longevity, p. 183.
It is very difficult to get statistics which bear upon the influence of mental labor on the brain, since the recorded occupation of an individual furnishes but a very rough estimate of the amount of thought evolved from his brain, and a very much less accurate one of what is probably of far greater importance—the amount of friction and anxiety with which it is done.
Hemorrhagic diseases may, for the sake of completeness, be once more mentioned as among the predisposing causes.
The exciting causes of cerebral hemorrhage are those which give rise to rupture of the fragile walls either of the aneurisms or fattily degenerated arterioles. They are to be found chiefly among such conditions as increase the pressure in the cerebral vessels, chiefly, though not wholly, from the arterial side. The connection of an attack of apoplexy with hypertrophy of the heart means, as has already been shown, in a great many cases, their mutual dependence upon arterial disease, as in chronic interstitial nephritis, but it seems probable also that an unusually powerful action of such a heart might be the immediate cause of the rupture. An excited action of the heart, connected with a dilatation of the cerebral vessels, naturally increases the strain on the weak portions, and we have thus the explanation of those instances where sudden or great excitement brings on the attack.
Apoplexy is less frequent in summer than in the other seasons, and it is especially remarked that sudden changes of temperature are likely to be accompanied by an unusual number of cases. Changes in the arterial tension consequent upon the varying amount of blood circulating in the skin are the probable connecting link.
Obstruction to the venous outflow, either alone or in conjunction with the preceding condition, has undoubtedly a marked effect. In addition to the cases of hemorrhage from veins obstructed by thrombi, already mentioned, instances of this method of production are to be found inthe effects of severe muscular effort, as in lifting, in straining at stool, or, as has occasionally happened, in coitu. It has been objected to the congestion theory of apoplexy that even in severe paroxysms of whooping cough, where the face becomes cyanosed and congested, nothing like unconsciousness or paralysis occurs; but cases have been reported where aphasia and cerebral hemorrhage into the optic thalamus and cortex have accompanied whooping cough. Violent convulsions may be the cause of cerebral hemorrhage, as in puerperal eclampsia.
Obstruction to the circulation in the neck by tight clothing may be a means of increasing the back pressure from the veins. It is said that deaths from apoplexy have been unusually frequent among soldiers who have been obliged to wear tight stocks for the sake of imparting what was supposed to be a more military bearing. Probably some of the hemorrhages found with valvular disease of the heart are to be explained by venous congestion, although others are due to embolism.
Blows and shocks to the head, not producing fractures, are occasional causes of cerebral and ventricular as well as of meningeal hemorrhage. Important medico-legal questions are likely to arise where both bruises externally and internal hemorrhage are found. It is important to recollect that ecchymoses of the pericranium16have been found in cases of apoplexy where no violence has been used. These may occur with occlusion of the cerebral vessels, as well as with hemorrhage, and are most likely to be situated on the paralyzed side, being sometimes distinctly limited at the median line. They have been supposed to be due to the general tendency of the blood toward the head, and to be of the same pathological origin as the cerebral lesion they accompany; but the fact that they may not be associated with hemorrhage proves that this explanation is inadequate. Another explanation attributes their causation to vaso-motor paralysis, together with some unknown factor present in only a certain number of cases. They may be compared to the subconjunctival hemorrhages seen after violent convulsions.
16Lepine,Archives de Physiologie, tome ii., 1869, p. 667.
Cerebral hemorrhage depending upon a blow is likely to be accompanied by meningeal bleeding; to be situated at some point of the cortex, and not in the regions more frequently affected; and to consist of the effusion of no great amount of blood, mixed with cerebral substance. There are also very often more than one. All the circumstances should be carefully weighed when, as not infrequently happens, there is doubt as to whether a blow was the cause of a hemorrhage, or whether a person found insensible, with a bruise upon his head, may have fallen down suddenly from an apoplectic attack. In the following case it would be difficult to be sure of the sequence: A negro man aged fifty fell backward from the first step of a ladder. He got up and went to work again, but soon became unconscious. He became partially conscious again in the accident-room of the hospital, but died in a few hours. There was no sign of injury to the head, but there was a rupture of an aneurism (not miliary) of the left middle cerebral artery, and hemorrhage into the meninges and all the ventricles. If the first fall had occurred in a scuffle, and the autopsy had been made in such way as not to disclose the aneurism, it might have been considered a case of homicide.