As to localized cerebral symptoms, aphasia occurred 53 times in a total of 96 abscesses of the left temporo-sphe noidal lobe. Hemianopsia was met with 6 times. Motor disturbances on the op posite side, whether of the nature of paralyses or as unilateral convulsions, were noted in 70 cases. Hammer:3alag (Monats. f. Olirenh., Jan., 1901).
In sinus-phlebitis the swelling back of the ear with tenderness on pressure and a cord-like hardness of the jugular at times will determine the nature of the condition with little difficulty. -Within the past year lumbar puncture has found some favor as a means of differentiating abscess from meningitis and sinus; thrombosis. If the fluid withdrawn is clear and does not contain micro-organ isms the disease is probably meningitis. Excess of leucocytes also indicates men ingitis. The diagnostic value of lumbar puncture is, however, exceedingly prob lematical as yet, and promises to remain so, in the opinion of the writer, so far as brain-abscess is concerned, for a very in definite future.
Most of the cerebral complications ob served occur in connection with chronic cases of suppurative otitis media. One should be chary, however, about making a diagnosis of brain-abscess in these cases on the first appearance of cerebral symp toms: it is better to watch the case for two or three days before deciding., as not infrequently apparently serious cerebral symptoms gradually disappear as a free discharge from the ear is established.
Above and back of the ear is the region of the brain concerned in the storage of the memories of the sounds of words. If this part of the brain is injiired. the person becomes linable to understand what is said to him. Again, everything that we call to mind by our visual sense employs the function of the occipital lobe of the brain: the visual centres. The connection between the hearing,-centres in the temporal lobe and the visual centres in the occipital lobe is made by a long tract lying under the cortex of the brain: a distinct associa tion-tract. When this tract is destroyed, as it often is in abscess of the temporal lobe. if one ask such a person what some object is that is held up before him, he recognizes the object, but cannot call it to mind and name it, because of the destruction of this association-tract.
This peculiar lack of association is an important symptom to elicit in cases of suspected abscess of the temporal lobe, yet it is not commonly mentioned in text-books. M. Allen Starr (Med. Dec., Dee. 11, '97).
Conclusions that in children the rapid progress, fever, and a history of injury or otitis generally make a diagnosis from tumor easy. In the slower eases, in which there is little or no fever, valuable assistance inay be obtained from lumbar puncture.
From acute meningitis the diagnosis is more difficult, and in the eases in which there are only terminal symptoms the diagnosis is impossible. In the more protracted cases the distinctive points with reference to abscess are the slower and more irregular course and, as a rule, a lower temperature. L. E. Holt (Archives of Pediatrics, Mar., '98).
In a case of pyinia of the sinuses accessory to the brain, or with a history of trauma with rapid loss of flesh and strength, the presence of a high tempera ture for a period of seventy-two hours, followed by a decline in temperature and an increase in the rapidity of the pulse, with pronounced flexure of the ex tremities, progressive increase in the dilation of the pupils, a half-unconscious condition with uncontrollable restless ness, peculiar indisposition of the pa tient to obey requests, the presence of sugar in the urine, slow respirations, tendency when standing to go toward one side, or swinging of the hands always toward one side, and the entire absence of paralysis, comprises a set of symptoms indicative only of abscess within the cerebellum. L. J. Hammond (Archives of Pediatrics, June, '99).
Etiology.—Abscess of the brain is always a secondary condition dependent upon the intracranial invasion of micro organisms from adjacent or remote sources of infection. Any one of the pus-producing micro-organisms may act as an exciting cause. The affection may occur at any age, but is most frequently observed in adolescence and middle adult life. It is rare in very young children (Holt) and in old age. Males are more often affected than females in propor tions varying from 3 to 1 to 5 to 1 ac cording to the observer. By far the most frequent source .of infection is purulent disease of the middle or internal ear.