Exploring the human brain using single-unit microelectrode technique during awake stereotactic functional neurosurgery.

Abstract

In neuroscience research, the use of true single-unit microelectrode technique has been confined largely to the animal neurophysiology laboratory due to the complexity of the equipment required and the fastidious, time-consuming nature of the methodology. We report here our successful clinical use of this technique in human patients with Parkinson's disease undergoing awake stereotactic movement disorder neurosurgery. The common targets in such operations are the postero-ventral portion of the globus pallidus interna in the basal ganglia (for dopa-induced dyskinesias particularly) and the ventro-intermediate nucleus of the thalamus (for tremor-predominant Parkinson's disease). Accurate and exquisite neurophysiological localisation of these small targets deep within the brain can be obtained with single-unit microelectrode technique prior to the insertion of a deep brain stimulator or definitive neurosurgical radiofrequency lesioning in the target area. This accuracy translates into better outcomes for patients and a reduced incidence of complications. The wealth of data gained from studying the abnormal behaviour of neurons within the basal ganglia and thalamus also provides us with fundamental insights into the pathophysiology behind Parkinson's disease.