Optimal targeting of deep brain stimulation in Parkinson’s disease

This PhD-thesis is a significant next step in optimizing Deep Brain Stimulation (DBS) for Parkinson's disease (PD), a sophisticated treatment in which electrodes are implanted into deep regions of the brain to mitigate symptoms. Key findings include the revelation that electrodes placed within 2mm of the intended target do not necessitate repositioning for effective motor improvement. This challenges the existing notion of a rigid surgical accuracy threshold, highlighting the need for transparent reporting on electrode placement. Furthermore, postoperative MRI and intraoperative CT are compared for electrode verification, with intraoperative CT emerging as a viable MRI alternative. Also, extended Hounsfield unit CT is introduced as an advanced imaging technique for superior visualization of electrode contacts, aiding in accurate verification of electrode positioning, to determine the need for surgical revision, and to inform DBS programming. Finally, this thesis explores the microlesion effect as a potential indicator of successful electrode positioning. It employs advanced imaging, such as 7-Tesla MRI coupled with diffusion-weighted imaging sequences, for visualizing relevant brain connectivity, aiming for personalized DBS strategies. Combined, the findings suggest that accurate electrode placement, informed by innovative imaging and connectivity insights, could significantly enhance DBS-treatment outcomes. This thesis underscores the potential of tailored DBS approaches, promising a future of improved care for PD patients.