We report a longitudinal follow-up study on six patients with chronic manganese-induced parkinsonism following cessation of manganese exposure. Compared with the 1987 study, their parkinsonian symptoms showed a slow progression, particularly in gait disturbances such as freezing during turning and walking backward with retropulsion. The mean disability scores on the King's College Hospital Rating Scale were 15.0 +/- 4.2 in 1987 and 28.3 +/- 6.7 in 1991 (p = 0.003, paired t test). Review of the video records also confirmed a worsening of parkinsonism, especially in difficulty turning. Three of six patients receiving levodopa treatment had an initial improvement. The response decreased after 2 to 3 years. During the therapy, they did not develop on-off fluctuation or dyskinesia. We conclude that patients with manganese-induced parkinsonism may develop increasing neurologic dysfunction long after cessation of exposure and that their responses to levodopa are different from those of patients with Parkinson's disease.

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A 15-year-old girl died 14 days after hemiplegia suddenly developed. On arteriography, intimal separation of the middle cerebral arteries showed as a long attenuated column of dye--the "string" sign. Pathologic examination showed intimal separation starting at the distal bifurcation of the right internal carotid artery and extending into the middle and anterior cerebral arteries. The arteriographic string sign as evidence of dissection may aid diagnosis of this cause of childhood hemiplegia.

Genetic haplotypes at five marker loci that are closely linked to the DYT1 gene on chromosome 9q were determined in 10 Ashkenazi Jewish patients with focal hand dystonia (eight with musician's cramp, two with writer's cramp). The founder haplotype associated with > 90% of cases generalized dystonia in the Ashkenazi Jewish population could not be constructed from any of the twenty chromosomes. Potential haplotypes were determined, and no common haplotype was discerned in these patients. These findings argue against a role for the founder mutation in the DYT1 gene in the etiology of occupational hand dystonia in this ethnic group. Further, if the DYT1 gene is involved in these later onset dystonias, there is no evidence for a common mutation in the Ashkenazic Jewish population. It appears that excessive, repetitive use, possibly in combination with ulnar neuropathy, may serve as the inciting cause of some focal dystonias.

A 55-year-old man had hydrocephalus caused by a third-ventricular tumor. Mentation improved after ventricular shunting and radiation therapy. Progressive hyperphagia, obesity, memory impairment, and hypersomnolence developed 13 months later, and he died 2 years after diagnosis. At necropsy, a gangliocytoma filled the third ventricle, resulting in compression and necrosis of the ventromedial and posterior hypothalamic nuclei. Clinical manifestations were attributed to these lesions.