Chapter 85 - Deep Brain Stimulation: Surgical Technique

Abstract

This chapter focuses on the surgical technique used during deep brain stimulation (DBS). Although there are reports of successful DBS surgery performed completely under general anesthesia, DBS is typically performed under conscious sedation or local anesthesia, in order to provide awake physiologic confirmation of the target. Physiologic confirmation of the target can be achieved via microelectrode recording (MER), usually combined with direct stimulation of the target either through a microelectrode (microstimulation), the DBS electrode (macrostimulation), or both. Stereotactic targeting can be accomplished in a number of commercially available navigation systems using reformatted stereotactic imaging sets. Targets can be identified with indirect or direct methods, although a combination of these is often preferred. Surgical implantation of implantable pulse generators (IPG) and DBS lead(s) can be completed on the same day or as staged procedures. MRI is the imaging modality of choice in stereotactic targeting and planning, allowing for accurate identification of the anterior commissure (AC) and posterior commissure (PC) and direct identification of targets or landmarks. Determining the initial stereotactic target is a crucial decision that is likely to influence the surgical outcome, operative time, and safety. The target can be localized either by directly identifying the structure in the preoperative images or indirectly. Indirect targeting relies on coordinates referenced to the midcommissural point (the midpoint of the AC–PC line) or on atlas-based outlines of subcortical structures fused and reformatted to fit the patient's preoperative images. The IPG is typically implanted in the infraclavicular region and connected to the DBS lead with an extension wire.