A system of practical medicine. By American authors. Vol. 5

by Unknown

Local spasms, which go under various names, as cramps, twitchings, epileptoid attacks, athetosis or athetoid movements, are common symptoms, particularly of growths which involve the cortical motor area. They are of great diagnostic value. They are commonly, although not invariably, accompanied by paresis, which is usually most marked in the part most affected by the spasm. These local spasms, beginning in one extremity, in a finger or toe it may be, often spread toward the centre, until they involve to a greater or less extent the whole limb, the side of the face, or one-half of the body. Sometimes instead of this they recur with the same definite movements over a long period. They are the expression of irritation of cerebral centres or tracts connected with the muscles or groups of muscles affected by the abnormal movement. They should always lead the physician to carefully consider the great probability of a lesion in some way involving the motor area.

Tumors of the cerebellum, pons, and medulla oblongata sometimes give rise to general convulsions which closely simulate attacks of grave epilepsy. These convulsions or general spasms are among the most important symptoms of intracranial neoplasms. More than paralysis, they may be regarded as general symptoms, as they are more likely to occur from tumors situated in different and distant regions of the brain than paralysis. They are by no means confined to cases in which the lesion is situated in the so-called motor area of the brain or in the cerebellum or pons-medulla region. Both physiological and pathological experiments have shown that convulsions violent in character, but having certain special characteristics, may originate from severe irritation of the dura mater. According to Duret,²⁴ irritation of the sensory nerves of the dura mater cause reflex spasms or contractures of the muscles of organic life. These spasms or contractures may occur in the face, eyeballs, neck, trunk, or limbs, and sometimes on one side and sometimes on the other. They tend to diffuse and invade neighboring groups of muscles. “They have never the localization, the measured and purposed character, of the contractions which belong to the lesions of the cortex. They frequently become transformed into permanent contractures.” The application of these facts and conclusions to brain tumors is evident. As neoplasms are so frequently connected, either directly with the dura mater or with the fused membranes, it is evident that the convulsive attacks from which the patient suffers may occur from tumors located anywhere within the cavity of the skull.

²⁴ Sur les Traumatismes cérébraux, par H. Duret, chapter iii., summarized in Brain. vol. i., 1878, p. 47.

General convulsions, as well as local or unilateral spasms, are present in many tumors of the motor cortex; but if their method of origin and their progress are closely watched they will usually be seen to begin with local twitchings.

A glance at the table will show examples of convulsion in almost every region of the brain.

Contractures—conditions of tonic spasm which continue more or less persistently—may be either early or late symptoms. They may occur in one or several limbs, in the face, or rarely in the neck. They are probably due in some cases to persistent irritation of the dura mater, in others to comparatively slight but continuous irritation of motor centres, and in still others to advanced degeneration of the motor tracts.

Choreas and choreic movements are not frequent, unless some of the forms of local spasm are regarded as local choreas. In one of Petrina's cases, a glioma involving the substance of both frontal lobes, choreic movements of the right arm were present, and in this same case tremor in both arms was also a symptom. Tremor simulating that of paralysis agitans or multiple cerebral sclerosis is occasionally observed, and sometimes a tremor which is nervous or hysteroidal in character is one of the results of the great suffering of the patient.

Paralysis or paresis is of course one of the most frequent evidences of the existence of an intracranial tumor. The palsies of cerebral tumors are chiefly unilateral, but the loss of power may be in one or both limbs, in one side of the face, or in the entire one-half of the body, according to location and extent. Tumors of the cortical motor zone usually begin their paralytic manifestations with paresis of one member or one side of the face, which goes on, as the growth increases in size, to more or less complete hemiplegia.

The paralysis which results from brain tumor is due either to pressure or to absolute destruction of tissue. In the latter case the destruction is brought about not only by the simple displacement of brain-substance, but also through the obliteration of blood-vessels and the consequent softening.

Peculiar forms of paralysis occur as the result of neoplasm growing in special locations, as will be more clearly shown under Local Diagnosis. Thus we have the alternating paralyses from tumors of the crus cerebri or of the lower part of the pons, and paraplegia, or perhaps what might be better called double hemiplegia, from multiple tumors which affect both sides of the brain. In rare cases paralysis of all four extremities has resulted from a growth in the middle line of the base of the brain. Some form of paralysis is recorded to have been present in 20 cases out of 100.