Directional versus omnidirectional Deep Brain Stimulation: Results of a multi-cente prospective blinded crossover study. (October 2020) - Schnitzler, A.; Mir, P.; Brodsky, M.; Verhagen, L.; Groppa, S.; Alvarez, R.; Evans, A.; Blazquez, M.; Nagel, S.; Pilitsis, J.; Pötter-Nerger, M.; Tse, W.; et al.