ABSTRACT
INTRODUCTIONAs a form of stereotactic functional neurosurgery, the surgical procedure for deep brain stimulation (DBS) relies upon neuroimaging for precise implantation of the DBS electrode. In current practice, surgical targeting is determined primarily by preoperative, image-guided surgical target/trajectory planning, magnetic resonance imaging (MRI) angiography to avoid blood vessels, and by intraoperative electrophysiological confirmation. Following surgery, imaging, usually in the form of computerized tomography (CT), is used to confirm targeting accuracy, which is a major factor in patient outcomes. Today, as imaging science continues to advance, it is also being used to improve our understanding of the central mechanisms of action of DBS.There is increasing evidence that DBS exerts both its therapeutic and adverse effects by modulating neural activity at the stimulation target site and brain structures that are functionally and anatomically related to it [3-7]. The brain’s dense wiring
has made characterizing the effect of electrical stimulation on neuronal communication beyond a few synapses challenging. However, functional and anatomical neuroimaging appears well suited to this task due to its wide clinical availability and global assessment capabilities. In the clinical setting and in basic and translational research, neuroimaging is helping to improve our understanding of the mechanisms and differential effects of DBS. This chapter reviews several types of clinical neuroimaging relative to their clinical application in DBS and their use as research tools with an emphasis on DBS for Parkinson’s disease (PD). NEUROIMAGING TECHNIQUESMuch progress has been made in the development of computerized medical imaging devices since the first use of CT in the 1970s and of MRI and PET in the 1980s [8-11]. Although we use the term “image,” the images are not photographs, but rather two-or three-dimensional computed images that reconstruct signals emitted by the human body under conditions specific to the type of detection method used. These noninvasive tools are widely applied both in the clinical arena and in neuroscience research for in vivo imaging of the structures and functions of the human brain. To better understand their use in the field of DBS, the basic principles of MRI and PET are explained in simple overviews in the sections that follow. For more detailed explanations on these techniques see MRI: The Basics on MRI [12] and Foundations of Medical Imaging on PET [13].
