Diagnosis.—Ordinarily it is quite ap parent in patients suffering from cere bral abscess that some affection of the brain exists. It is by no means so easy always to decide that the symptoms are due to abscess. The diseases which most often confuse the diagnosis are menin gitis, tumor, and sinus-phlebitis. The difficulty encountered in differentiating brain-abscess from sinus-phlebitis and meningitis is increased by the fact that the same causes may operate to produce either of them. This is especially true of trauma and the various infectious dis eases and also of disease of the internal ear, though the latter points to abscess rather than meningitis or phlebitis. In all three the temperature is affected, but it is usually above normal and sometimes quite high in meningitis and phlebitis, while it is either below normal or quite irregular in abscess.
Although ahnost all observers agree that subnormal temperature is the rule in brain-abscess, it must not be depended upon. Case in which the temperature reached to 105° or 106° F., and was so irregular as to suggest pymmia and thrombosis of the lateral sinus. Again, nuich stress is laid upon the presence of a cerebellar gait, yet this was often the result of irritation of the auditory nerve or of irritation of the semicircular canals. Optic neuritis is sometimes present, but not often, probably because there was no time for it to develop. M. Allen Starr (Med. Rec., Dec. 11, '97).
Cerebellar abscess may be distinguished from labyrinthine disease by its more violent headache, its persistence, and its location; and by the somnolence which increases from day to day. In abscess of the temporo-sphenoidal or occipital lobes of the cerebrum there are motor affections, paresis, contractures, spasms. but always on the side opposite to that of the lesion or the otitis; and aphasia and hemianopsia are important signs. In glioma, gliosarcoma, tuberculorna, and parasitic tumors of the cerebellum there is a tendency to produce other than local symptoms. Syphilis must always. be carefully sought for in the history. Dieulafoy (Le Progres June 30, 1900).
In menin,c!itis the onset is usually more acute, the symptoms more diffused, the delirium is more conspicuous, the tendency to rigidity and generalized spasm is more marked; there is photo phobia and a state of wide-spread cuta neous hypermsthesia with accelerated respirations and irregular, high pulse. Focal symptoms are less common in meningitis except in cases affecting the base, when the number and degree of involvement of eranial nerves is more marked than in cerebral abscess. If the meningitis is localized and circum scribed, I do not believe it is possible to make the differentiation positively. Tenderness of the skull over the site of the disease points to abscess rather than meningitis in such cases.
Traumatic brain-abscesses may be con founded with traumatic meningitis, apo plexy, encephalitis, tumor, epilepsy, and traumatic neuroses. A one-sided trau matic apoplexy or a haemorrhagic non purulent encephalitis may, from symp toms alone, easily be taken for abscess.
Suppurative meningitis occurring with an abscess is likely to be overlooked. An abscess of the brain is marked by normal or subnormal temperatures; fever is by no means a necessary symptom. If
an attack begins with a rise of tempera ture, it is probably not due to an ab scess of the brain, certainly not to an uncomplicated one. A slow pulse is, per haps, the most reliable single symptom.
Patients suffering from ear troubles often become hysterical, and a hasty diagnosis of hysteria, even if the typical symptoms are present, may falsely be made in cerebral abscess of the otitic origin. Oppenheim (Fortsehritte der Med., Nov. 15, '96).
Case of cerebral abscess in a child 3 months old. First symptoms were of intestinal initation. Later developed a swelling in the region of the anterior fontanelle. Temperature was 104.5° F. The elevated tumor fluctuated slightly, but distinctly, on pressure, and was of an erythematous cast. There was no ear disease, and child was perfectly healthy. Upon punctming the dura, it was tough and resisting; cutting for ward for about an inch all was well. The longitudinal sinus was punctured, and packing had to be employed and further operation postponed. Packing was removed nt end of forty-eight hours. 'hemorrhage had ceased. Packing WaS again replaced. On removing packing next day it was saturated with greenish, foul discharges, which welled up from the bottom of the wound; about three fluidrachms came out. The cavity was washed out with 1 to 5000 bichloride of-mercury solution and packed. The wound healed under this treatment, and patient recovered. W. J. Doyle (N. Y. Med. Jour., July 29, '99).
Symptoms of brain-abscess due to middle-ear suppuration based on 195 cases. It occurs most frequently in early middle life. Out of 175 cases in which the sex was stated, 122 were males and only 53 were females. In 1S1 cases of temporo-sphenoidal abscess 85 occurred in the right hemisphere and DO in the left. The variations in the temperature show no characteristic feature, normal or subnormal, a slight or even a considerable rise being vari ously observed, the complications, such as meningitis or sinus-phlebitis, account ing for these. The uncomplicated must be separated front the complicated be fore positive deductions can be drawn. The temperature variations noted in 170 eases were: Normal, 46; elevated, 106; subnormal, 18. In eases of uncompli cated brain-abscess the temperature is raised in about one-half. Chills are not frequently noted. The most frequent of the cerebral symptoms is headache, which was present in 103 eases. Stiff ness of the neck was noted 12 times, and general convulsions 10 times. Gen eral headache is valueless as a sign, but localized headache and tenderness are of some diagnostic importance. It seldom declares itself, however; in 28 cases it was on the same side as the abscess, while in 14 other cases tenderness in the temporal region of the same side was complained of. Disturbance in cerebra tion occurred in more than one-half of the cases. Mental symptoms were rare, and the sensory disturbances ranged from a slight form of slow cerebration to loss of consciousness and coma, which occurred in 74 cases. Even heavy stupor did not adversely influence operative procedure. The pulse was slowed in 73 instances. In 60 cases changes in the fundus were noted.