[CT-guided stereotaxic implantation of a deep brain electrode for the stimulation of the internal capsule--a case report].
A 47-year-old man was admitted to our clinic because of the pain of left extremities for four years. The patient developed dysesthesia, hyperpathia and spontaneous pain 2 months after the onset of cerebrovascular accident with left hemiparesis. Using Toshiba TCT-20A CT scanner and Leksell's CT-stereotaxic system, stimulation electrode (by Medtronic Co.) was implanted in the posterior limb of the internal capsule which was 25 mm lateral to the posterior commissure. Ventriculography was not necessary because the target point was directly measured from the axial CT and midsagittal reformatted CT based on 18 axial CT images (2 mm thick slices). Anterior commissure, pineal calcification, posterior commissure and Sylvian aqueduct were demonstrated on the midsagittal reformatted CT by this method. The pain was relieved by the ramped square pulse stimulation (2 V, 0.6 msec, 50 Hz) and receivor system was internalized. The patient was free from pain by 30 minutes-long stimulation four to six times a day. Precise electrode placement was possible by CT images alone using high resolution CT and CT-stereotaxic system. CT-guided stereotaxic technique seemed to have an advantages especially for the implantation of electrode in the posterior limb of the internal capsule. The reason is as follows: The target is just lateral to the posterior commissure which could be recognized easily on the midsagittal reformatted CT. The internal capsule is advantageously demonstrated on the axial CT.
D001921:Brain / Q000000981:diagnostic imaging / Q000601:surgery*; D004599:Electric Stimulation Therapy; D004567:Electrodes, Implanted; D006801:Humans; D008297:Male; D008875:Middle Aged; D010148:Intractable Pain / Q000628:therapy; D013238:Stereotaxic Techniques; D014057:Tomography, X-Ray Computed