Summary: Purpose:We report on the efficacy and safety of extended one-stage callosal section performed in a large and homogeneous series of patients.Methods: Seventy-six patients with Lennox-Gastaut (n = 28) and Lennox-like (n = 48) syndrome were studied (42 male patients; mean age, 11.2 years). All patients had multiple seizure types per day, including atonic, tonic-clonic, atypical absence, myoclonic, and tonic seizures. All of them were developmentally impaired. The EEG showed intense secondary bilateral synchrony in all of them. All patients were submitted to an extended, one-stage, callosal section, leaving only the splenium intact. Mean follow-up time was 4.7 years.Results: Worthwhile improvement (>50%) was noted in 69 of 76 patients; 52 patients had a ≥90% reduction in seizure frequency. Seven patients were seizure free after surgery. The seizure patterns most responsive to surgery were atonic (92%), atypical absence (82%), and tonic-clonic (57%) seizures. All patients had some degree of a transient acute postoperative disconnection syndrome. A consistent increase in attention level was observed postoperatively.Conclusions: We report one of the larger homogeneous series of patients submitted to callosotomy and are the first to report on the effectiveness and safety of performing extended callosal section in a single stage in this patient group. Extended callosal section should be considered a good palliative surgical option for suitable candidates. The increase in attention level was as useful as seizure control in improving quality of life of these patients.

Summary:Purpose: To study the efficacy of extensive coverage of the brain surface with subdural grids in defining extratemporal cortical areas amenable for resection in patients with refractory extratemporal epilepy (R-ExTE) and normal or nonlocalizing magnetic resonance imaging (MRI) scans.Methods: Sixteen patients with R-ExTE were studied. Eleven patients had simple partial, eight had complex partial, and three had supplementary motor area seizures. Seizure frequency ranged from three per month to daily episodes. Interictal EEG showed large focal spiking areas in 11 patients, secondary bilateral synchrony in four, and was normal in one patient. Surface ictal recordings were nonlocalizing in six patients, and in 10, they disclosed large ictal focal spiking areas. MRI was normal in 10 patients, and in six patients, focal nonlocalizing potentially epileptogenic lesions were found. All patients were given an extensive coverage of the cortical convexity with subdural electrodes through large unilateral (n ‫ס‬ 13) or bilateral (n ‫ס‬ 3) craniotomies. Bipolar cortical stimulation was carried out through the implanted electrodes.Results: Interictal invasive recording findings showed widespread spiking areas in 13 patients and secondary bilateral synchrony in three. Ictal invasive recordings showed focal seizure onset in all patients. There were six frontal, two parietal, one temporooccipital, four rolandic, and three posterior quadrant resections. Thirteen patients had been rendered seizure free after surgery, and three had ജ90% of seizure-frequency reduction. Pathologic findings included gliosis (n ‫ס‬ 10), cortical dysplasia (n ‫ס‬ 5), or no abnormalities (n ‫ס‬ 1). Six patients had transient postoperative neurologic morbidity.Conclusions: Extensive subdural electrodes coverage seems to be an effective way to investigate patients with R-ExTE and normal or nonlocalizing MRI findings.

SUMMARYPurpose: To study the outcome after hemispherectomy (HP) in a homogeneous adult patient population with refractory hemispheric epilepsy. Methods: Fourteen adult patients submitted to HP were studied. Patients had to be at least 18 years old, and have refractory epilepsy, clearly focal lateralized seizures and unilateral porencephalus consistent with early middle cerebral artery infarct on magnetic resonance imaging (MRI). All patients were submitted to functional hemispherectomy. We analyzed age of seizure onset, age by the time of surgery, gender, seizure type and frequency, interictal and ictal electroencephalography (EEG) findings, MRI and IQ scores preoperatively; seizure frequency, drug regimen, and IQ outcome were studied postoperatively. Results: Mean follow-up was 64 months. All patients had frequent daily seizures preoperatively. All patients had unilateral simple partial motor seizures (SPS); 11 patients had secondarily generalized tonic-clonic (GTC) seizures and five patients had complex partial seizures (CPS), preoperatively. All patients had hemiplegia and hemianopsia. Twelve patients had unilateral EEG findings, and in two epileptic discharges were seen exclusively over the apparently normal hemisphere. Twelve patients were seizure-free after surgery and two patients had at least 90% improvement in seizure frequency. Pre-and postoperative mean general IQ was 84 and 88, respectively. Five of the twelve Engel I patients were receiving no drugs at last follow-up. There was no mortality or major morbidity. Conclusions: Our results suggest that wellselected adult patients might also get good results after HP. Although good results were obtained in our adult series, the same procedure yielded a much more striking result if performed earlier in life.

SUMMARYPurpose: We report on the surgical outcome obtained in patients with refractory temporal lobe epilepsy with mesial temporal sclerosis (MTS) who were evaluated preoperatively without ictal recording and were submitted to corticoamygdalohippocampectomy. Methods: Two hundred twelve patients with refractory temporal lobe epilepsy were evaluated by means of clinical history, neurological examination, interictal electroencephalography (EEG), magnetic resonance imaging (MRI), and neuropsychological testing. MRI disclosed unilateral MTS in all patients. All patients were submitted to corticoamygdalohippocampectomy at the side determined by MRI. Results: Interictal EEG showed unilateral temporal lobe spiking in 176 patients; in 36 patients, bilateral discharges were found. Mean follow-up time was 2.7 years. One hundred ninety-four patients (92%) were classified as Engel's class I. Eighteen patients (8%) were rated as Engel's class II. Thirtytwo out of 36 patients, in whom bilateral discharges were found, were in Engel's class I. Sixty percent of the patients had an improvement in memory function related to the nonoperated temporal lobe. Fifty-nine percent of the patients had a 10-point increase in general IQ postoperatively. Verbal memory decline was noted in three patients. Pathological examination showed MTS in all patients. Conclusions: It is possible to adequately select good surgical candidates for temporal lobe resection using MRI and interictal EEG alone. In patients with MRI-defined MTS, we should expect a 90% postoperative remission rate. Cognitive decline was very rarely seen in this patient population. The finding of MTS on MRI is the single most important prognostic factor for good outcome after temporal lobe surgery.

Good surgical outcome (77% seizure-free patients) could be obtained even in this apparently unsuitable group of patients. All patients benefit from the procedure. We did not see any cognitive decline in our patients with severe bilateral MTS. Patients with severe bilateral MTS would need invasive recordings despite any findings during surface video-EEG.