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CEREBRAL CIRCULATION IN THE INSANE.
BY W. B. FLETCHER, M. D., SUPT. IND. HOSPITAL FOR THE INSANE.
The following observations made by the Pathological Society of the Indiana Hospital for the Insane are presented for the purpose of drawing out the observations that may have been made by others in autopsies upon persons not insane.
The usual method pursued in our examinations was to remove the calvarium, after noting any external peculiarities that might exist, and then make a study of the brain in situ-the condition of the dura-and, after its removal, of the vascular membranes. The brain was then generally removed with great care, particular attention being given to dividing the carotid and vertebral arteries. If the arteries have not been previously injected with a hard injection, one of the vertebrals is ligated and the cerebral vessels injected direct; but, at times, to test the integrity of the various vascular regions of the brain, injections have been made into the vessels having origin from the circle of Willis.
The class of persons examined were, without exception, chronic insane, some of whom were epileptic; and as we intend to confine this short paper to the cirulation as there observed, I will state in brief that the general weight of the brain was above the average, bearing out the conclusions of Boyd (British Medical Journal, Sept. 1876, page 425), when he found in an examination of 2,050 brains that the insane averaged higher than the sane, he giving the weights as follows: sane males, 47.5; insane males, 48.2; sane females, 41.9; insane females, 43.2.
There was the same general appearance of congestion of the vessels of the membranes that one finds in the various forms of death, either congestive type or anemic forms.
The first unvarying condition that has attracted most attention has been the irregular arrangement of the vessels at the base of the brain, which may have been congenital anomalies, or have become so through complete or partial obliteration from embolia or other cause. Most usual is the diminution of one of the vertebral arteries, as will be seen on the specimen here exhibited, and also the drawings which are made by actual measurement.
The second peculiar deviation from the normal standard hås been the great variation in the number of branches given off from the basilar, the post cerebral, Sylvian, and cerebral arteries, this variation extending as much as twenty or thirty branches; in this specimen the Sylvian has 64; in this but 44.
The third deviation is noted in the post communicating arteries, where frequently one is nearly obliterated, and the other normal or enlarged.
The fourth, and one that exists as an index of acute disease at some time, is the obliteration of arterial capillaries or obstruction of some of the larger branches. The specimens here exhibited will illustrate each point in the above statements.
The fifth observation has been that the jugular fossa is larger and deeper upon one side, and that the foramen lacerum posterius is either greatly contracted, or is extremely large upon one side.
And sixth, that an examination of the interior and exterior of cranii which I have collected of persons who have died insane, shows that there is an almost total obliteration of the various foramina, which admit the venous blood from without the cranium to the venous sinuses that collect the blood of the brain centers, and carry it away to the great jugular vein.
Finally, the choroid plexus was usually cystic.
The result of the whole number of observations shows that in these insane persons there has been an unvarying irregularity of the blood supply to some portion of the brain; that too much has been sent to some part, not enough to others, and that venous blood that should be admitted was perforce stagnated upon the surface.
We are forced to the conclusion that in the study of cerebral pathology, too much attention has been given to the distribution of nerve fibres or the arrangement of nerve cells; too much study
of cut micro-sections of cord or brain, and too little to the blood. supply upon which the integrity and function of the cells and fibres depend. Elements of the cord and brain are not likely to become diseased from any cause within themselves—the mind is only deranged when the supply of blood in quantity or quality is changed.
The fact that the arterial supply is through terminal arteries, and that they form no anastomoses with each other, every branch acting independently and supplying its own section, center or convolution, is enough to point to the cerebral physiologist that his only way to a true localization of function of the various parts of the brain will be by most careful study as a pathologist. Thus Charcot, Durant and Hubner made a proud progress in a field neglected by BrownSequard, Ferrier and others.
The brain may be likened to a garden of rare plants, watered by irrigation. So long as the water supply is equally distributed, each variety having the quantity due its special nature, then does it flourish in its beauty and perfection; but if the ditch become obstructed, or is made too large for some plants and too small for other varieties, a condition of drouth and death will prevail on one hand or a bog will be formed on the other, making monstrosities or growing wild and strange vegetation.
It will be remembered that insanity is a disease of mature life, although the brain of an adult weighs no more than at twelve to sixteen years old. Is it not because the anchylosis of the cranial bones at the base is not completed until about twenty-one to thirty years of age, particularly the basi-occipital and sphenoidal, which form the foramen lacerum posterior, through which pass the jugular veins and meningeal branches of the pharyngeal and occipital arteries and eighth pair of nerves? The bones do not become anchylosed until from twenty to thirty years of age, a period most common for development of the hereditary form of insanity.
There are many cases recorded in which twins become insane within a days of each other; a case of this kind is now in our hospital. Could such coincidences likely arise from any other cause than that at the same age the peculiarities of their osseous structure were completed and the circulation alike changed?
Kasloff, of the University of Kiew, has noted that many cases
of mania of suicides show a great contraction of the foramen lacerum posterior, and the few observations made at the Indiana Hospital for the Insane confirm it; one shows the further change of diminished carotids and all other cerebral arteries.
Prof. Nape, of Bonne, noted many years ago the frequency of heart disease with insanity, and several hundred examinations here show that about 75 per cent. of our insane have marked disturbance of the heart and disease of the larger arteries; it is not unlikely that inflammatory disease, affecting the endocardium, sends newly formed matter to the brain through the carotid, which finds lodgement in the terminal branches, and causes death of the locality thus arterialized, and consequent insanity.
Retarded venous circulation, producing pressure on intercranial nerves, may likewise produce derangements of the mind, as it frequently does of the respiratory organs through pressure on respiratory centers.
There is no doubt that tubercles deposited upon the capillary expansion of the cerebral arteries cause insanity just as sunstroke does, by depriving the cortical substance and ganglionic centers of blood supply. Syphilitic gummata and bone deposit act in the
There have recently been published reports of ligation of the vertebral arteries for epilepsy, and the reports would indicate that it was a very successful treatment of that worst of all diseases, but I can not think in the end the results would be better than that doubtful procedure of ligation of the internal carotids. Sir Astley Cooper found, both in man and lower animals, degeneration of the brain followed. And Norman Cheevers, in tabulating all cases of such ligation up to his time, remarks that "when recovery followed tying the primitive carotids, a considerable number became hemiplegic and perished from diseases of the hemisphere of the brain."
I have but one more point to make regarding the arterial circulation, and that is that the first branch given off from the middle meningeal, or Sylvian, is the choroid, which forms within the lateral ventricle a most beautiful and curious plexus, in which plexus two-thirds of the cases show cystic formation from the size of the smallest bird shot to a filbert. I am fully satisfied in my own
mind, and think it can be demonstrated by the microscope upon any fresh specimen, that this plexus, so-called, is glandular in structure and function, and that its ducts open into the so-called pineal gland, and, like that body, contain acervulus cerebri and corpora amylacea. I will state that this brain sand and starch granules can not be demonstrated until the body is cold. How far the cysts may go to produce mental derangement can not be known until the practical pathologist has made many thousands of observations. and careful records.
Finally, do not construe my remarks to mean that there is no insanity except from some derangement in the structure of the
vessels of the brain.
There are many forms of emotional disease where the mind becomes affected without permanent change, and which might be called sympathetic or functional insanity; or, again, where the blood has conveyed toxic substances instead of nourishment to the brain centers, as in the temporary insanity of alcoholism, opium, etc., or uremic and other blood poisons; but, upon such cases we have had no opportunity to study in the dead-house and laboratory.
My firm conviction is that the more thorough study of the venous and arterial circulation in disease of the brain will give to the progress and treatment of the insane a degree of certainty heretofore unknown.
So long as we can not, by way of experimental test, ligate the arteries which supply different convolutions, lobules, and special areas of brain matter, and thereby note what new, or what loss of function there is, we must take the next best method—that is, of having a thorough knowledge of the mental and physical peculiarities during the life of the insane person, and after death search out the abnormal vascular relation. This can only be done by injecting the vessels with some substance to distend them (the brain will not hold more than one and a half to two ounces of the material). After the injection each artery should be followed from its origin to its termination. In this way the dead branches, so to speak, can be discovered.
I call attention to one point which I do not think has ever been noted in the medical literature of this subject, and that is, that in normal condition, the vascular membrane dips deeply into all the