5.3.5\ Deep Brain Stimulation (DBS)

5.3.5.1\ Discussion

DBS is used to treat symptoms of Parkinson’s disease, essential tremor, Tourette’s, and intractable thalamic pain syndrome, among other conditions. Electrodes can be introduced via burr holes into the thalamus, globus pallidus, cerebellum, or subthalamic nucleus depending on the underlying condition (Figs. 5.37 and 5.38). Precise positioning of the electrodes can be achieved by the use of intraoperative stereotactic guidance and physiologic localization. The electrodes are comprised

a

c

of insulated metallic wires that are connected to a pulse generator and battery pack that are buried in the subcutaneous tissues of the scalp, chest, or abdomen, depending on the model and number of pulse generators required. Although the electrodes are normally secured to the calvarium, displacement is a potential complication that can be readily assessed on CT (Fig. 5.39). Other complications include electrode fracture, “twiddler syndrome,” and hemorrhage along the electrode tract, which is actually more common after removal (13%) than during insertion (2%), and ischemic infarction (0.4%) (Fig. 5.40).

b

Fig. 5.39  Electrode migration. Initial postoperative axial (a) and coronal (b) CT images show satisfactory positioning of bilateral globus pallidus internus electrodes in a

patient with dystonia. Subsequent axial (c) and coronal (d) CT images show marked interval retraction of the right electrode