In mild cases, should death occur, it is likely that no characteristic nor well marked anatomical alterations would detected. In severe cases there are changes in the neurone bodies of the cerebral cortex and lenticular nuclei paralleling those of fatigue, as de scribed by Hodges and others, together with, in cases of long standing, distinct degenerative changes in nervous ele ments of the cortex, pyramidal tracts, and cord. When these degenerative al terations are well marked, it is likely that the clinical picture during life was that of chronic adult chorea, rather than Sp.len ham's chorea. In addition to the changes in the nervous elements themselves, there are, in severe and long-continued cases, secondary changes in the con nective-tissue structures and blood-ves sels, perivascular dilatation, accumula tions of round cells in lymph-spaces, etc. In acute cases there are often small areas of softening, with congestion and capil lary dilatation in cortex and lenticular nuclei. In maniacal chorea the cortex and pia mater are chiefly involved, there being usually intense hypermmia, with evidences of acute inflammation. The changes resemble those of violent acute mania or delirium.
Report of thirty-nine autopsies. The chief changes were just beneath the cor tex, where the white matter was honey combed with little spaces, round or oval. These spaces were empty or partly filled with blood-vessels. The process, he be lieves, was non-inflammatory, and was due to abnormal dilatation and filtration of the vessels' contents. The same changes were found in the basal ganglia and the internal capsule, whose fibres were split up by interlaced and dilated vessels. There was also noticed a vari cosity of the nerve-fibres. ln the re corded cases the most marked changes were hyperminia. periarterial exudations, erosions, softened spots, multiple limmor rhages, and occasionally embolisms. The changes are most marked in the deeper parts of the motor tract; but Ile con siders chorea not as a local disease, but as a disease of the intracranial motor tract, including its starting-point in the cortex and especially in its co-ordinating adjuncts,—the lenticular nucleus and thalamus. Dana (Brain, Oct., '90).
An affection of cerebra] cortex. Loss of control which sensitive areas possess over motor areas. Brush (New York Med. Jour., Mar. 9, '95).
Case of a girl of 12, in whom chorea set in six weeks after a first attack of acute rheumatism and a fortnio.ht after the first subjective sign.s of cardiac im plication. Bronchitis, and eventually double pneumonia, supervened, and the patient died just a month after the commencement of the chorea. The ne cropsy was made four hours after death, which was found to be due to double pneumonia, with staphylococcal endo carditis and pericarditis. Multiple
thrombi, colorless. red, mixed. and hy aline, were found in the central nerv ous system, particularly the cerebrum. There was a deposit of (dotty masses in the adventitia, of a medium-sized vein in the globus pallidus, and of numerous fat-globules in and on the cerebral blood-vessels. There had been a con siderable amount of sensory disturbance in the case, due probably to the naultiple thromboses. The symptoms of chorea due to vasomotor disturbances in the brain as the result of the rheumatic toxceinia. The thromboses are the extreme expres.sion of these changes. Okada (Mitteil. der med. Facia. der kaiser]. Japan. Univ. zu Tokio, 1902).
Prognosis.—The rule in chorea is a gradual and insidious onset, a slow rise in intensity and distinctness of symp toms, followed by a stationary period of weeks or several months, and a gradual subsidence of the disease, with final re covery. The malady is acute and quite curable, with a natural tendency to re covery, even when not treated at all. Some mild cases recover in a few weeks; two to three months is the duration of the typical forms, although occasionally the symptoms may persist for six or more months. Some nervousness and slight twitchings noticed when the child is startled or excited may continue for months after recovery, and a species of chronic "habit chorea" may be the final result. A true chronic chorea rarely or never follows this variety of neurosis in children, but is occasionally seen after acute chorea in adults. In general, how ever, a chronic chorea in adults or in children is apt to be associated with de generation of the cortical motor cells and pyramidal tracts, thus differing widely from the form of acute chorea under consideration. The milder forms of chorea are unattended by danger to life. Chorea insaniens is often fatal, and, where recovery from the acute afFection occurs, there is danger of some perma nent mental deterioration.
Relapses after apparent recovery are not rare. The existence of a compli cating rheumatism or endocarditis is thought to favor relapse.
The result in any case of chorea is largely influenced by the complications and underlying cause.
Treatment and Prophylaxis.—In view of the frequency with which chorea de velops in intelligent and ambitious chil dren of neurotic heredity who are over worked at school, something may be done toward preventing the develop ment of the disease by insisting upon moderation in study and a proper ob servance of the rules of physical and mental hygiene.