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The pathology of Parkinson's disease (PD) is not confined to the nigrostriatal dopaminergic pathway, but also involves widespread cerebral cortical areas. Such non-nigrostriatal lesions may contribute to disabling dopa-resistant parkinsonian motor deficits. We performed cortical thickness analysis to identify cerebral cortical brain areas in which thickness correlates with the severity of parkinsonian motor deficits. We performed T1-weighted brain magnetic resonance imaging studies in 142 PD patients. Motor scores on the Unified Parkinson's Disease Rating Scale (UPDRS) were measured, and subscores were calculated for bradykinesia, rigidity, tremor, and axial motor deficits. Using FreeSurfer software, we studied cortical areas in which thickness correlates with disease duration or the severity of parkinsonian motor deficits. The cortical thickness of the parieto-temporal association cortex, including the inferior parietal and posterior parietal cortices, showed a negative correlation with disease duration, total UPDRS motor score, and UPDRS subscores for bradykinesia and axial motor deficits. We found no cortical areas in which thickness correlated with subscores for tremor and rigidity. In addition to nigrostriatal dopaminergic deficit, progressive thinning of the parieto-temporal sensory association cortices related to disease duration seems to be related in part to the exacerbation of bradykinesia and the axial motor symptoms of PD.

Two women with typical stiff-man syndrome (SMS) developed increasingly frequent attacks of muscle spasms with severe paroxysmal autonomic dysfunctions such as transient hyperpyrexia, diaphoresis, tachypnea, tachycardia, pupillary dilation, and arterial hypertension. Autoantibodies to GABA-ergic neurons were identified in the serum of both patients and in the cerebrospinal fluid of one. Both died suddenly and unexpectedly. General autopsy did not reveal the cause of death. Neuropathological studies revealed perivascular gliosis in the spinal cord and brain stem of one patient and lymphocytic perivascular infiltration in the spinal cord, brain stem, and basal ganglia of the other. The occurrence of a chronic inflammatory reaction in one of the two patients supports the idea that an autoimmune disease against GABA-ergic neurons may be involved in SMS. A review of the literature indicates that functional impairment in SMS is severe and prognosis is unpredictable because of the potential for sudden and unexpected death. Both muscular abnormalities and autonomic dysfunctions may result from autoimmunity directed against GABA-ergic neurons.

A case of acute severe generalized muscle rigidity in a 16-month-old child is described. The arm flexors and leg extensors were the most severely involved, with all stretch reflexes absent. Motor conduction velocities on the arms and legs were very slow and nerve potentials were not elicited. The rigidity and electromyographically recorded spontaneous activity almost disappeared on carbamazepine treatment, with nerve conduction velocities remaining unchanged.

F-wave responses from abductor pollicis brevis muscle occurred more frequently, with a larger amplitude and longer duration in rigid parkinsonian patients than in age-matched normal controls. F-wave potentiation during voluntary contraction was impaired in parkinsonian patients. These findings suggest that spinal motor neuron excitability is enhanced in rigidity. F-wave amplitude was significantly correlated to the clinical evaluation of motor disability, so that the F wave may be regarded as a useful approach to quantitative evaluation of rigidity.

Three female cases of the "rigid spine" syndrome are reported and associated with different nosological entities. One patient was affected by congenital muscular dystrophy and one by a morphological pattern of fibre type disproportion with type I atrophy. The third patient showed very peculiar morphological changes on a muscle biopsy specimen resembling a vacuolar myopathy, which is rarely described in association with the rigid spine syndrome. The importance of an adequate investigation of the rigid spine syndrome and the recognition of the presence or absence of cardiomyopathy, if there is to be correct genetic counselling, is discussed.

A 28-year-old male with generalized muscle stiffness and widespread muscle twitching is described. Continuous electrical activity was present at rest and could be abolished only by succinylcholine, curare, and block of the distal part of the peripheral nerve. Muscle biopsy revealed mild myopathic changes. In addition glycogen depletion was found in muscle fibres which were type IIb in one region of the biopsy and type I in another. With carbamazepine treatment marked improvement occurred both clinically and electromyographically. It is concluded that the abnormal electrical activity originated in the terminal branches of the peripheral motor nerve and that this activity was confined to muscle fibres belonging to single motor unit territories.