Having satisfied ourselves that organic disease of the brain is present, the next question to determine is: Is it tumor? It is rare that tubercular meningitis is likely to be mistaken for tumor, except possibly in those cases which run a pro longed course. These are often attended with tubercular nodules or even a tuber cular growth of considerable size. Un der such circumstances the symptoms will partake of the character of menin gitis and intracranial tumor, those of the latter predominating when the growth is large, and those of the former when the deposits are small. In those cases in which a tumor has existed prior to the development of meningitis, not infre quently a history of attacks of appar ently-causeless vomiting, attended with severe headache, may be obtained. An eurism is diagnosticated by detecting a bruit. The principal symptoms of chronic cerebritis are headache, vomit ing, and distinct optic neuritis, without localizing symptoms. This condition probably cannot be distinguished from cular condition of the meninges attended with great thickening of the membranes to such an extent as to give rise to dis tinct focal symptoms is clinically indis tinguishable from an intracranial tumor. Alcoholic meningitis usually affects the convexity, and tremor is present. One needs only to be familiar with the delu sions of grandeur, the character of the mental failure, and other symptoms com mon to paretic dementia to prevent his tumor of the brain unattended by focal symptoms and pronounced choking of the disks. Chronic hydrocephalus with effusion into both lateral ventricles need not be mistaken for tumor if the symp toms of each are borne in mind and the history of the case is carefully studied. Distension of one lateral ventricle with pronounced unilateral choked disk was mistaken by me for tumor in a case in which the history was unobtainable. A syphilitic meningitis or a nodular tuber confounding it with tumor of the brain. The same may be said of the other forms of insanity, especially mania. In mul
tiple sclerosis the tremor is bilateral; in tumor with tremor the latter is usually unilateral. The atypical symptoms of hysteria and paretic dementia often found in diffuse sclerosis of the cere brum will aid in preventing this disease from being mistaken for tumor. In dif fuse sclerosis if the cerebellum is affected and there is staggering gait, with a tend envy to fall to one side, the absence of severe headache, optic neuritis, and vom iting will be against tumor and in favor of diffuse sclerosis. Chronic abscess of the brain does not cause total blindness or very marked choking of the optic disks.
What is the seat of the tumor? If the tumor is in the premotor region of the frontal lobe, there may be few posi tive focal symptoms. Headache is rarely so agonizing, vomiting so constant, or choked disk so frequent as in tumors in the posterior portion of the brain. My experience has been that choked disk is absent in about one-half the cases of tumor of the premotor region of the frontal lobes. The mental symptoms are the most constant, but these are variable. The patients may be apathetic, disregard the ordinary proprieties of life, and be come filthy and partially demented as the disease progresses. Some exhibit a childishness foreign to their nature, and talk much of trivial things, especially when these relate to themselves; others are irritable, impatient, and at times may show a maniacal tendency; while nearly all manifest a lessened power of sustained attention and mental concentration, with absent-mindedness and lack of judgment. Amnesia is rarely complete unless the tumor is very large or both lobes are in volved. If the tumor extends backward motor symptoms become manifest, and disturbances of speech are added in le sions of the left side in right-handed persons. Ataxia of the cerebellar type has been observed by a few in tumors of the frontal lobe.