To determine the effect of electrode contact location on efficacy of bilateral globus pallidus internus (GPi) deep brain stimulation (DBS) for primary generalised dystonia (PGD). Subjects and
Unit of Functional Neurosurgery, Sobell Department, Institute of Neurology, University College London, Box 146, 8-11 Queen Square, London WC1N 3BG, UK. s.tisch@ion.ucl.ac.uk