Exploring a new direction in deep brain stimulation

This thesis investigates the clinical value of directional deep brain stimulation (DBS) in the treatment of Parkinson’s disease and other neurological conditions. DBS (the surgical implantation of electrodes that deliver targeted electrical impulses to specific brain regions) has become an established advanced therapy for managing the debilitating motor complications of Parkinson’s disease. Conventional omnidirectional leads disperse current in all directions, which can inadvertently stimulate adjacent structures and cause adverse effects. Directional DBS technology, using segmented electrode contacts, offers the ability to steer the electrical field with greater precision, theoretically widening the therapeutic window and reducing side effects.
To evaluate whether this theoretical advantage translates into real clinical benefit, this thesis takes a stepwise approach. Questionnaire and survey studies first established the clinical landscape: neurologists estimated that up to 21% of DBS patients could benefit from directional leads, and early adopters worldwide confirmed its practical utility for troubleshooting suboptimal outcomes — though programming complexity and lack of standardized protocols remained consistent challenges.
The centerpiece of the thesis is the STEERING trial, a multicenter, double-blind, randomized crossover study directly comparing directional and omnidirectional subthalamic nucleus DBS. While primary motor outcomes were equivalent between the two modalities, directional DBS yielded meaningful improvements in speech, walking, and adverse effect thresholds, with a majority of patients expressing a preference for directional stimulation.
The thesis further explores stimulation configurations, a novel application of directional DBS for central poststroke pain, and the unintended consequence of newer technology elevating patient expectations beyond what current evidence supports.
Together, these studies position omnidirectional DBS as the appropriate first-line strategy, with directional DBS as a clinically valuable tool for individualized optimization.