Assessment of contact location in subthalamic stimulation for Parkinson's disease by co-registration of computed tomography images.

Aims: To study the validity of a co-registration method for postimplantation computed tomography (CT) images for localizing the location of an intracranial deep brain stimulator.

Methods: Three-dimensional reconstruction images of postimplantation CTs were co-registered with preoperative CTs by stereotactic planning software and used to localize 18 leads in the subthalamic nuclei of 10 patients with Parkinson's disease. Our conventional method using superimposition of sagittal postimplantation magnetic resonance (MR) images were employed as a comparison.

Results: The co-registered CT images separately visualized four individual contacts; on the other hand, the MR superimposition method demonstrated the leads as a group of no MR signal areas. Although laterality of the distal contact did not differ between two methods, the distal contact was located more anteriorly and inferiorly by the MR superimposition method than by the CT co-registration method.

Conclusion: The CT co-registration method is superior to MR in visualizing deep brain stimulation contacts and resolves problems of MR safety in patients treated with a neurostimulator.