Olivopontocerebellar atrophy in children: a report of seven cases in two families

We present seven cases of progressive ataxia with onset in childhood along with pathological findings in three patients. One patient showed pure cerebellar degeneration and had no visual changes. His brother had classic changes of olivopontocerebellar atrophy with profound amyotrophy but no visual changes. A third family member had similar findings with pathological findings intermediate in severity between the first two. The mother and daughter, who are living, are ataxic and have macular degeneration. In a second pedigree, all patients affected in three generations were male, but the disease began during adulthood in the first two generations. Myoclonic seizures occurred in the majority of patients.

Field testing of an ataxia scoring and staging system

The authors present a simple system for disability scoring and functional staging of an ataxic patient, based on modifications of a previous scheme advocated by De Falco and collaborators (1979). This system was tested under field conditions in 47 ataxic subjects and found to be useful and functional.

Leucocyte glutamate dehydrogenase in various hereditary ataxias

Leucocyte Glutamate Dehydrogenase (GDH) activity was measured in 44 patients with various forms of ataxia and 44 age and sex-matched normal controls. The only significant change found was a moderate decrease in activity in Friedreich's ataxia and a few patients with OPCA. This decreased activity is not primary to the disease but probably reflects a regulatory defect affecting mitochondrial membranes in these patients.

Impedance audiometry in the squirrel monkey. Effect of transection of crossed olivocochlear bundle

Acoustic reflex thresholds in squirrel monkeys did not show any statistically significant change following midline section of the crossed olivocochlear bundle. Lack of agreement with the results reported by Borg in rabbits is most probably due to the species difference.

Myelin basic protein depolarizes neuronal membranes

Bath application of 10(-5) M myelin basic protein (MBP) to various types of cultured nerve cells resulted in a membrane depolarization amounting to a change of 41 +/- 15 mV. Excitability could be restored by repolarizing the membrane by means of current injection through the recording electrode. The action of MBP persisted in the presence of tetrodotoxin (TTX), Co2+ or D-600 as well as in low Na+ and low Cl- solutions, whereas it was abolished by increasing extracellular Ca2+ concentrations. The action MBP was mimicked by ouabain. We propose that the effect of the protein might be generated by blockade of an ion pump. It is speculated that MBP may exert a direct effect on neuronal membranes in demyelinating diseases.

Computerized tomography and auditory-evoked potentials. Use in the diagnosis of olivopontocerebellar degeneration

The pneumoencephalogram has been the only diagnostic test available to confirm the diagnosis of olivopontocerebellar degeneration during life. This study suggests that pneumoencephalography may be obsolete and that the diagnosis of olivopontocerebellar degeneration may be established by abnormalities seen during computerized tomography (CT) and by abnormal responses to auditory-evoked potentials (AEPs). The combination of CT scans and AEPs provides a completely nontraumatic method of diagnosis in olivopontocerebellar degeneration and eliminates the need for pneumoencephalography.

Urine vapor pattern for olivopontocerebellar degeneration

Autosomal dominant olivopontocerebellar degeneration was evaluated in a family numbering 414 living members. Urine samples were obtained from 5 affected and 5 unaffected not at-risk family members after 4 days on a synthetic diet. 159 urine vapor constituents were measured by gas-liquid and ion-exchange chromatography and a non-correlation index was calculated. 2 distinct populations of urine vapor patterns were identified which conformed to the normal and disease affected groups, thus a diagnostically useful pattern for this disease in this family has been demonstrated which will be helpful in genetic counselling and potential elimination of the disease.

Olivopontocerebellar degeneration. Clinicopathologic correlation of the associated retinopathy

In two siblings with olivopontocerebellar degeneration, the retinal pigment epithelium or the sensory retinal or both appeared to be damaged first. These layers were markedly involved before secondary changes in the choriocapillaris, the inner retinal layers, or the optic nerve occurred.