Pedunculopontine nucleus stimulation induces monocular oscillopsia

Université Joseph Fourier, Grenoble, France and INSERM U836, Grenoble Institut des Neurosciences, Grenoble, France.
Journal of neurology, neurosurgery, and psychiatry (Impact Factor: 6.81). 03/2009; 80(2):228-31. DOI: 10.1136/jnnp.2008.146472
Source: PubMed

ABSTRACT Two patients with Parkinson's disease with pedunculopontine nucleus (PPN) stimulation for gait impairments reported "trembling vision" during the setting of the electrical parameters, although there was no clinically observable abnormal eye movement. Oculomotor recordings revealed frequency locked voltage dependent vertical or oblique movements of the eye ipsilateral to the active contact, suggesting current spreading to the mesencephalic oculomotor fibres. These results emphasise the difficulty of stimulating this mesencephalic region.

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    • "PPNa stimulation induced adverse effects at relatively low voltages, including oscillopsia and limb myoclonus at low frequency and paraesthesia at higher frequencies. The oculomotor effects are likely to result from the recruitment of the most lateral and caudal fibres of the oculomotor nerve (Ferraye et al., 2009). "
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