Stereotaxy

BACKGROUND: Stereoelectroencephalography (SEEG) methodology, originally developed by Talairach and Bancaud, is progressively gaining popularity for the presurgical invasive evaluation of drug-resistant epilepsies. OBJECTIVE: To describe recent SEEG methodological implementations carried out in our center, to evaluate safety, and to analyze in vivo application accuracy in a consecutive series of 500 procedures with a total of 6496 implanted electrodes. METHODS: Four hundred nineteen procedures were performed with the traditional 2-step surgical workflow, which was modified for the subsequent 81 procedures. The new workflow entailed acquisition of brain 3-dimensional angiography and magnetic resonance imaging in frameless and markerless conditions, advanced multimodal planning, and robot-assisted implantation. Quantitative analysis for in vivo entry point and target point localization error was performed on a sub–data set of 118 procedures (1567 electrodes). RESULTS: The methodology allowed successful implantation in all cases. Major complication rate was 12 of 500 (2.4%), including 1 death for indirect morbidity. Median entry point localization error was 1.43 mm (interquartile range, 0.91-2.21 mm) with the traditional workflow and 0.78 mm (interquartile range, 0.49-1.08 mm) with the new one (P , 2.2 · 10 216). Median target point localization errors were 2.69 mm (interquartile range, 1.89-3.67 mm) and 1.77 mm (interquartile range, 1.25-2.51 mm; P , 2.2 · 10 216), respectively. CONCLUSION: SEEG is a safe and accurate procedure for the invasive assessment of the epileptogenic zone. Traditional Talairach methodology, implemented by multi-modal planning and robot-assisted surgery, allows direct electrical recording from superficial and deep-seated brain structures, providing essential information in the most complex cases of drug-resistant epilepsy.

The effective treatment of intracranial abscess remains controversial. Progress in technology, linked with the development of neuronavigational systems, has made stereotactic aspiration and drainage of intracerebral abscesses effective and valid alternatives to traditional methods, namely, conservative medical treatment or open surgical excision. Between 1995 and 2002, 12 patients at our hospital underwent drainage of intracerebral abscesses under stereotactic guidance. Ten patients had solitary lesions and two had multiple abscesses. The appropriate antibiotic schemes were administered following culture of the aspirated material. The size of the abscess, the mass effect, and response to antibiotic treatment were followed up by repeated CT scans. All patients showed improvement and, at the end of treatment, returned to their previous activities. There were neither deaths nor any postoperative complication. A second aspiration was required in one patient due to recurrence of the absc...

The authors developed a new method of drug delivery into the brain using implantable, biodegradable microspheres. The strategy was evaluated initially to provide localized and sustained delivery of the radiosensitizer 5-fluorouracil (5-FU) after patients underwent surgical resection of malignant glioma. In this study, the microspheres were implanted by stereotaxy into deeply situated and inoperable brain tumors. Ten patients with newly diagnosed, inoperable, malignant gliomas were included in the study, and 1 dose of 5-FU was studied (132 mg). After histologic confirmation, a suspension of poly(D-L lactide-co-glycolide) 5-FU-loaded microspheres was implanted by stereotaxy into the tumor in one or several trajectories with one to seven deposits per trajectory. External beam radiation (59.4 grays) was started before postoperative Day 7. Patients were followed by clinical examination, computed tomography scanning, magnetic resonance imaging, and 5-FU assays in blood and cerebrospinal f...