or more, situated indiscriminately. They are, however, commonly located in the white matter of the hemispheres, or of the cerebellum, and rarely in the gray matter, or at the base of the brain. They vary in size up to one and a half or two inches in diameter. More recent abscesses have a shreddy wall, older ones have a definite and often thick cyst wall or capsule, composed of fibrillated, if not fibrous, tissue. The pus is mostly greenish in color, viscid, and acid in reaction; but in long-standing cases it becomes more mucoid still, alkaline, and of bright green color. Sometimes, especially when due to bone disease, it may be extremely offensive. The brain tissue outside the abscess may be softened. Though in many fatal cases the abscess is found intact, it may rupture into the membranes, and set up meningitis, or into the lateral ventricles, or it may form a communication, through diseased bone, with the tympanum, and discharge externally (otorrhea cerebralis). Symptoms. These are often extremely obscure. The most constant is pain, of continuous dull aching character, or more severe, so that the patient holds his head with his hands, or bores his head into the pillow, or cries out constantly. Exacerbations of the pain occur from time to time. The seat of the pain often, but not always, corresponds to the position of the abscess. Sometimes there is elevation of the temperature, sometimes rigors, either occasionally or following with such regularity as to suggest ague. In a case which was almost certainly abscess of the brain, there were drenching perspirations a few days before death. Convulsions and vomiting also occur. Optic neuritis is much less frequently present than in cases of tumor. Alteration in manner, dullness, listlessness, loss of memory, and emaciation, are also sometimes observed. The common seat of the abscess renders localizing symptoms on the part of the motor tract or nerve trunks rather uncommon; but there may be ill-defined hemiplegia, or aphasia, or some implication of one or more of the cranial nerves, and, in abscess of the cerebellum, some uncertainty of gait. The duration of the symptoms is very variable; they may last for months, or they may end fatally in a few weeks. Death is often quite rapid, the patient becoming delirious, or quickly drowsy and comatose. Respiration may cease before the pulse, as in the sudden deaths from cerebral tumor. Diagnosis. The diagnosis of abscess of the brain is not always easy; its pain may be mistaken for neuralgia, and its rigors for ague. The most important factor in diagnosis is the presence of a primary cause, and chronic discharge from the ear is the most frequent of these. It must not, however, be too hastily assumed that acute head pains and pyrexia. occurring in a patient the subject of chronic otitis are due to cerebral abscess, even though rigors and optic neuritis be present as well. For otitis may produce, besides abscess of the brain, subdural abscess or meningitis, or simple suppuration of the mastoid cells with or without thrombosis of the adjacent veins and sinuses. All of these are accompanied by severe head pains, and fever; with mastoid abscess there may also be rigors. And it is important to remember, which has now been verified in numerous cases, that in mastoid suppuration there is often double optic neuritis, with an entire absence of meningitis or of abscess, as proved by post-mortem examination, and by recovery after simply trephining the mastoid cells. The cause is probably thrombosis of some cerebral sinuses. This warning, however, applies almost more to meningitis than to abscess, since optic neuritis is less frequent in the latter. Suppurative meningitis-the form most likely to be confounded with abscess, since they have a common origin is more rapid in its course, and is more likely to be accompanied by paralysis and fits; the temperature is more uniformly high, and shivering is absent. Prognosis. This is very unfavorable, but not always hopeless. Treatment. Where an abscess can be with certainty recognized, and its locality accurately determined, there is a possibility of evacuating the pus by surgical means. Several successful cases, thus treated, have been recorded in recent years. In two of the first published cases, the abscess was arrived at by continuous exploration through the diseased bone which was the cause of the abscess. In Dr. Gowers' case, Mr. Barker, after finding that thorough local treatment of the tympanum and mastoid cells, though relieving partially, still left dangerous evidence of abscess, trephined-one inch and a quarter above and the same distance behind the external meatus. The dura mater was found healthy, and the abscess was reached through half an inch of brain tissue. In Dr. Greenfield's case symptoms, especially ptosis and oculo-motor paralysis, pointed to a more anterior position of the abscess, and the trephine was applied, in front of the ear, an inch above the zygoma, and one and a half inches behind the external angular process. Pus was found immediately within the dura mater. The uncertainties of diagnosis make it desirable that before trephining a thorough exploration and antiseptic treatment of the tympanum and mastoid cells should be undertaken, both to exclude the possibility of the symptoms being entirely due to these parts, and also, as Mr. Barker suggests, to minimize the risk of meningitis during the longer operation. Apart from surgical interference, the treatment of abscess of the brain must be purely symptomatic; the relief of pain may be attempted by local anodynes, by ice to the head, bromide of potassium, butyl-chloral hydrate, etc.; and large doses of quinine may be given, in the hope of neutralizing the septic condition. .i DISSEMINATED SCLEROSIS. This disease, which is also called multiple sclerosis, and insular sclerosis (sclérose en plaques disseminées, Charcot), is characterized by the development of numerous patches of chronic inflammation or sclerosis, throughout the central nervous system. It has been described as occurring in three formscerebral, spinal, and cerebro-spinal; but the last is by far the most frequent. At an autopsy of such a case the surface of the spinal cord, medulla oblongata, and pons and base of the brain present a number of irregular patches of pinkish-gray color, rather sharply outlined, and contrasting with the natural white color of the medulla, pons, and crura. On section, the discoloration is found to extend inward so as to form deposits of a round or oval shape, ranging in size from that of a pea to that of a hazelnut, generally harder than the normal nervous tissue, and even leathery, or cartilaginous; sometimes projecting above the level of the section, sometimes below it. Recent patches are dark gray, older patches more yellowish-gray, and less translucent. They affect the white matter more than the gray matter; thus in the spinal cord the greater part of the cornua is unaffected, and in the cerebrum they are best seen on section of the hemispheres, which are dotted with the gray areas, and the walls of the lateral ventricles are often invaded. They are not frequent in the cerebellum; but the sclerosis may invade the olfactory bulbs, and the spinal and cranial nerve-roots. Under the microscope the outline of the patch or nodule is much less distinctly marked than it appears to the naked eye. The nodule consists chiefly of fibrous or finely fibrillated tissue, with some nuclei, granular corpuscles, and here and there still persistent axis-cylinders, although the majority of the nerve fibres may be entirely destroyed. The walls of the vessels are also thickened, and surrounded with nuclei, or they may be in a state of fatty degeneration. Etiology. The disease has no marked preference for one sex over the other. It occurs mostly in youth or middle age, and cases are recorded of the characteristic symptoms even in children. Cold, mental worry, or excitement, injuries, and acute diseases have been assigned as causes in different cases. Symptoms. The onset of the disease is very variable: sometimes it is quite gradual, and the patients simply notice that they get weaker, or nervous, or tremulous. In other cases there has been an apparently more rapid beginning the knees have suddenly given way, or there has been sudden weakness of one arm and leg, which have perhaps recovered after a time; but weakness in all the limbs has subsequently occurred. When the disease is fully developed the following three symptoms are nearly always prominent, and present a picture which is, on the whole, very characteristic. They are(1) Tremor of muscles on attempting to move; (2) a peculiar manner of speaking, syllabic or scanning speech; and (3) nystagmus. The tremor is best observed in the hand and arm when the patient attempts to take hold of an object-the limb oscillates irregularly to the right and left, or up and down, with regard to the object aimed at, the excursions from the straight line being often several inches in extent. When the patient sits up in bed, or stands up, the body swings to and fro, and the head undergoes a series of nodding movements; while in the attempt to walk the movements of the legs are similarly unsteady. When the patient is lying quiet in bed, or sitting with the back, head, and arms supported, he is perfectly quiet. The movements are more violent the greater the effort, and the more the patient feels that he is under the observation of others. In talking, every syllable is distinctly uttered in a slow, deliberate manner and somewhat suddenly, as in the staccato delivery of music. There is little or none of the natural slurring of some syllables and accentuation of others. The voice is also rather high-pitched and monotonous. It has been observed with the laryngoscope that the vocal cords are apt to relax in phonation, and to undergo rapid changes of tension. The nystagmus, or oscillation of the eyeballs, is, like the movement in the limbs, only brought on by voluntary movements-that is, when the eyes are fixed upon an object, or when they are much turned to one side. It is thus unlike the oscillation seen in some cerebellar tumors, or the constant movement which occurs in some diseases of the fundus of the eye. The other symptoms that may occur are-modifications of sensation, such as numbness or formication, but rarely complete anæsthesia; and rigidity of the lower extremities. This is pronounced in some advanced cases, where it may co-exist with actual paralysis, from the sclerosis invading nearly the whole thickness of the cord at one spot, and thus, like a transverse myelitis, producing paraplegia. But in earlier stages rigidity with extension and adduction of the legs may be a troublesome symptom, and the gait will have a spastic character. Occasionally, atrophy of muscles is observed, when it may be supposed that sclerosis has invaded the gray cornua. Mostly, electric irritability is normal; only in later stages reaction may be diminished, or become "degenerative," where muscular atrophy is present. The bladder, rectum, and sexual organs often retain their power, or there may be some impairment of the functions of the bladder-involuntary expulsion or slight retention. There is sometimes defect of vision, with diminution of the field and achromatopsy, and rarely complete blindness. In such cases. a partial optic atrophy has been seen. Headache and vertigo are occasionally present. More frequent is some impairment of the mental or emotional powers. The patients are especially liable to laugh or cry without apparent reason, and the intelligence is weakened as the disease progresses. Delusions of grandeur may occur, and the case may ultimately assume all the characteristics of general paralysis of the insane. In some instances, peculiar apoplectic attacks occur. The patient is seized with headache, giddiness, rare. then loss of consciousness, and weakness of the arm and leg on one side. The face is red, the pulse is frequent, and the temperature rises to 104° or 106°. Recovery takes place in a day or two. Epileptiform attacks are more Occasionally the usual symptoms may be absent, and death takes place from an apoplectic attack; and in others, from special localization of the patches, the various chronic spinal diseases, myelitis, spastic paraplegia, or bulbar paralysis may be simulated. But it is remarkable how constantly the three symptoms first mentioned are the prominent features of the case. The disease may last several years-ten, fifteen, or twenty. Death may take place much earlier from an apoplectic seizure, or the patient may be bed-ridden for years with paraplegia, and die from the accidents associated with that condition or from intercurrent disease. Pathology. The symptoms are not at present satisfactorily explained. The tremors have been referred by some to the want of "insulation" of the axis-cylinders in the sclerosed patches, impulses being there irregularly transmitted. Others attribute the symptoms to the patches which invade the pons Varolii or the higher parts of the motor tracts. Diagnosis. This is easy when the three cardinal symptoms are alone prominent. The tremors can scarcely be confounded with chorea or paralysis agitans. In chorea, the movements are more twisting, jerking, or writhing, and occur during rest. In paralysis agitans they are regular and rhythmical, more rapid, and less extensive; they occur during rest, and may, in early stages, be stopped by voluntary effort. The oscillating movements which are seen in disease of the cerebellum closely resemble those of sclerosis, but the former may be distinguished by the other evidences of local disease. It may be, as already implied, that they have the same origin. Charcot says that chronic cervical meningitis with cortical sclerosis may produce similar tremors. Mercurial tremors resemble disseminated sclerosis in the movements of the limbs, but the head and trunk are less affected in the former. In particular cases there may be some difficulty in distinguishing the disease from the chronic spinal complaints already mentioned, especially if, as is sometimes the case, the tremor is absent. In the early stages, patients may be thought to be hysterical, or, on the other hand, hysteria may simulate sclerosis. The Prognosis is bad, and the Treatment mainly symptomatic. Any direct treatment would naturally be similar to that of locomotor ataxy or chronic myelitis. MENINGITIS. Acute inflammation of the membranes of the brain is seen chiefly in two forms, one suppurative, the other characterized by the presence of tubercles, tubercular meningitis. From a clinical point of view it is perhaps preferable to describe the tubercular form first. |