A prospective long-term study on the outcome after vagus nerve stimulation at maximally tolerated current intensity in a cohort of children with refractory secondary generalized epilepsy.

INTRODUCTION: We report the outcome after vagus nerve stimulation (VNS) in children with secondary generalized epilepsy. METHODS: Twenty-four consecutive children with Lennox-Gastaut or Lennox-like syndrome under the age of 12 years by the time of surgery, who were implanted with a vagus nerve stimulator and had at least two years of postimplantation follow-up, were prospectively included in the study. The generator was turned on using 0.25 mA, 30 Hz, 500 µsec, 30 sec "on," 5 min "off" stimuli parameters; current was then increased by 0.25 mA every two weeks, until 3.5 mA was reached or adverse effects were noted. RESULTS: Magnetic resonance imaging was normal or showed atrophy in 13 children. Six children got an end-of-study (24 months) postimplantation video-electroencephalogram, and their findings were similar to those before VNS. Quality of life and health measures improved in up to 50% (mean = 25%) in 20 children. Attention was noted to improve in 21 out of the 24 children. Final intensity parameters ranged from 2 to 3.5 mA (mean = 3.1 mA). An implantation effect was noted in 14 out of the 24 children, and lasted a mean of 20.2 days. There were 47 seizure types among the 24 children. An at least 50% seizure frequency reduction was noted in 35 seizure types and 17 seizure types disappeared after VNS. Atypical absence, myoclonic and generalized tonic-clonic seizures were significantly reduced by VNS; tonic and atonic seizures did not improve. Transient seizure frequency worsening was noted in ten of the 24 children, at a mean of 3.1 mA. DISCUSSION: Our study showed that VNS was effective in reducing atypical absence, generalized tonic-clonic, and myoclonic seizures (but not atonic or tonic seizures) in children with Lennox-Gastaut or Lennox-like syndrome. A concomitant improvement in attention level and quality of life and health also was noted. Secondary generalized epilepsy represents a subset of good candidates for VNS.

Vagus nerve stimulation might have a unique effect in reflex eating seizures.

We studied the effects of vagus nerve stimulation (VNS) on eating seizures, which theoretically would be triggered by neural activity and signaling from organs innervated by the vagus nerve. Three adult patients with daily nonreflex and reflex eating seizures were studied; one patient also had hot-water seizures. One patient had bilateral polymicrogyria and two had normal magnetic resonance imaging (MRI) findings. All patients were submitted to VNS implantation and had at least 2 years of postimplantation follow-up. Final stimulation parameters were 2.0-2.5 mA, 500 micros, and 30 Hz. Eating seizures decreased 70-95% and nonreflex seizures decreased 0-40% after VNS. There was no improvement in hot-water seizures. VNS seems to be an especially useful treatment modality in patients with reflex eating seizures not amenable to resective surgery.

Parkinsonism induced by VNS in a child with double-cortex syndrome.

We describe a child with epilepsy associated with double-cortex syndrome in whom vagus nerve stimulation (VNS) generated parkinsonian symptoms. A 13-year-old girl presented with refractory secondary generalized epilepsy from the age of 6 years and mental retardation. Her electroencephalography (EEG) showed diffuse polyspike and wave discharges. Magnetic resonance imaging (MRI) showed double-cortex syndrome. She was submitted to extended callosal section at the age of 10 years, which yielded 50% seizure frequency reduction. She was submitted to VNS by the age of 12 years. As stimulation intensity was increased, there was appearance of extrapyramidal symptoms: She developed bilateral tremor and rigidity, and gait and postural disturbance. All symptoms disappeared 7-10 days after VNS was turned off. Several attempts to reactivate VNS led to the same results. During the periods when VNS was on she presented with marked seizure frequency reduction. This is the first report of a clinically evident direct effect of VNS on the basal ganglia.

Outcome after corticoamygdalohippocampectomy in patients with refractory temporal lobe epilepsy and mesial temporal sclerosis without preoperative ictal recording.

PURPOSE: 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. Thirty-two 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.

Outcome after extended callosal section in patients with primary idiopathic generalized epilepsy.

PURPOSE: We report the outcome of patients with refractory idiopathic generalized epilepsy (IGE) who were submitted to extended one-stage callosal section. METHODS: Eleven patients with IGE who were submitted to extended one-stage callosal section were studied. Preoperative workup included history and neurologic examination, interictal, and ictal electroencephalography (EEG) recording, high resolution 1.5T magnetic resonance imaging (MRI) and intelligence quotient (IQ) testing. All patients were submitted to extended one-stage microsurgical callosal section, leaving only the splenium intact. RESULTS: Preoperative ictal patterns included repetitive spike and wave or polyspike and wave discharges or fast epileptic recruiting rhythm. MRI showed no focal lesions. Preoperatively, mean general IQ was 85. Postoperatively, at least a 75% reduction in the frequency of generalized tonic-clonic seizures was noted in all patients. In three patients absences disappeared completely, and the others had at least 90% reduction in seizure frequency. Only one patient had myoclonic seizures preoperatively, and these seizures disappeared after callosal section. After surgery, mean general IQ was 89. A very clear increase in attention level was noted in all patients. Postoperative interictal EEG recordings showed rupture of bilateral synchrony in all patients. DISCUSSION: This article reports on a large and homogeneous series of patients with refractory IGE submitted for callosal section. There was a marked decrease in generalized seizure frequency and increase in the attention level in this patient population. Our results suggest that corticocortical interaction might have a role in IGE pathogenesis. Callosotomy is a safe, effective, and underused palliative procedure in these well-selected patients with refractory IGE.

Outcome after hemispherectomy in hemiplegic adult patients with refractory epilepsy associated with early middle cerebral artery infarcts.

PURPOSE: 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 well-selected 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.

Surgical outcome in patients with refractory epilepsy associated to MRI-defined unilateral mesial temporal sclerosis.

INTRODUCTION: Several pre-operative work-up protocols have been used while selecting epileptic patients for surgery among different centers. The relative value of the different available pre-operative tests is still under discussion. OBJECTIVE: We report on the surgical outcome obtained in patients with refractory temporal lobe epilepsy associated to mesial temporal sclerosis (MTS) and who were evaluated pre-operatively by interictal EEG and MRI alone. METHOD: Forty one patients with refractory unilateral temporal lobe epilepsy were evaluated using interictal EEG and MRI. MRI disclosed unilateral MTS in all patients. All patients had at least 4 interictal EEG recordings. All patients were submitted to cortico-amygdalo-hippocampectomy at the side determined by MRI. RESULTS: Interictal EEG showed unilateral epileptiform discharges compatible with MRI findings in 37 patients; in four out of the 41 patients, bilateral discharges were found. Mean follow-up time was 4.3+/-1.1 years. Thirty-nine patients (95.1%) were classified as Engels Class I (70.6% Engel I-A). Two patients (4.9%) were rated as Engel's Class II. All patients in whom bilateral discharges were found were in Engels Class I. Pathological examination showed MTS in all patients. CONCLUSION: 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 postoperative remission rate higher then 90%. The finding of MTS on MRI is the most important good prognostic factor after temporal lobe resection.

Seizure-related outcome after corticoamygdalohippocampectomy in patients with refractory temporal lobe epilepsy and mesial temporal sclerosis evaluated by magnetic resonance imaging alone.

OBJECT: The authors conducted a study to assess the efficacy of surgery in patients who underwent magnetic resonance (MR) imaging alone for localization of foci in temporal lobe epilepsy (TLE). METHODS: One hundred patients (43 men, 57 women) with a clinical diagnosis of TLE were prospectively studied (mean age 28 +/- 9 years [+/- standard deviation {SD}]). All patients underwent high-resolution MR imaging, and in all unilateral mesial temporal sclerosis (MTS) was diagnosed by visual inspection. All patients underwent interictal preoperative electroencephalography (EEG) and in 87 patients pre- and 1-year postoperative neuropsychological testing was performed. Both EEG and neuropsychological examinations were conducted in a blinded fashion, and these data were not taken into account during the surgery-related decision-making process. All patients underwent a corticoamygdalohippocampectomy at the side of the MTS. Surgery-related outcome was rated as Class I (seizure free or simple partial seizures only) or Class II (> or = 90% improvement). The follow-up period ranged from 18 to 48 months (mean 24 +/- 5 months [+/-SD]). No patient underwent prolonged video-EEG monitoring, Wada testing, positron emission tomography, or single-photon emission computerized tomography. In eighty-nine patients Class I results were achieved, and 11 Class II results were achieved postoperatively. There was no mortality in this series. Except for in two patients who underwent surgery in the dominant temporal lobe, there was no postoperatively cognitive decline. In these two patients verbal memory decline occurred, which was associated with posterior temporal cortical damage, demonstrated postoperatively on MR imaging. Twenty-five percent of the patients experienced improved memory function related to the nonoperated side, and 54% experienced a 10% gain in general intelligence quotient status. CONCLUSIONS: In patients with clinically suspected TLE, MR imaging alone is able to localize temporal lobe foci correctly. Ruling out pseudoseizures remains the only indication for prolonged video-EEG recordings in this group of patients.

[Early functional hemispherectomy in hemimegalencephaly associated to refractory epilepsy]. / Hemisferectomia funcional precoce na hemimegalencefalia associada à epilepsia refratária.

Hemimegalencephaly (HME) is a rare congenital brain malformation of unknown etiology. Patients with HME can present with an early onset epileptic syndrome which is often refractory to medical treatment and associated to impaired neurological development. Functional hemispherectomy (FH) has proven to be a valuable treatment alternative in patients with refractory epilepsy in this setting. Very few children operated under the age of 6 months and bearing HME and catastrophic epilepsy (CE) have been described in the literature. This study reports on 2 kids younger than 6 months with HME and CE submitted to FH with good clinical outcome.

Long-term outcome after callosotomy or vagus nerve stimulation in consecutive prospective cohorts of children with Lennox-Gastaut or Lennox-like syndrome and non-specific MRI findings.

PURPOSE: There is currently no resective (potentially curative) surgical option that is useful in patients with Lennox-Gastaut syndrome. Palliative procedures such as callosotomy (Cx), vagus nerve stimulation (VNS) or deep brain stimulation have been offered. We compared the outcomes after Cx or VNS in two consecutive prospective cohorts of patients with generalised epilepsy. METHODS: Twenty-four patients underwent callosotomy from 2006 to 2007 (Group 1); 20 additional patients were submitted to VNS from 2008 to 2009 (Group 2). They had generalised epilepsy of the Lennox-Gastaut or Lennox-like type. They were submitted to a neurological interview and examination, interictal and ictal video-EEG, high resolution 1.5T MRI, and cognitive and quality of life evaluations. The two-year post-operative follow-up results were evaluated for each patient. RESULTS: The final mean stimuli intensity was 3.0 mA in the Group 2 patients. Seizure-free patients accounted for 10% in Group 1 and none in Group 2. Ten and sixteen percent of the Group 1 and 2 patients, respectively, were non-responders. Improvements in attention and quality of life were noted in 85% of both Group 1 and 2 patients. Rupture of the secondary bilateral synchrony was noted in 85% of Group 1 patients; there was no EEG modification after VNS in Group 2. Both procedures were effective regarding the control of atypical absences and generalised tonic-clonic seizures. Both procedures were not effective in controlling tonic seizures. Callosotomy was very effective in reducing the frequency of atonic seizures, but VNS was ineffective. In contrast, callosotomy was not effective in reducing myoclonic seizures, whereas VNS was. DISCUSSION: Callosotomy might be preferred as the primary treatment in children with Lennox-Gastaut syndrome, and no specific findings on MRI if atonic seizures prevail in the patient's clinical picture; when myoclonic seizures prevail, the same might hold true in favour of VNS. When atypical absence or generalised tonic-clonic seizures are the main concern, although both procedures carry similar effectiveness, VNS might be considered a good option as an initial approach, taking into account the adverse event profile. Patients should be advised that both procedures are not very effective in the treatment of tonic seizures.

Speech preservation using a non-linear paradigm for determination of the extent of neocortical resection in patients with mesial temporal sclerosis submitted to cortico-amygdalo-hippocampectomy (CAH).

RATIONALE: The rationale for using a non-linear (proportional) paradigm for determining the extent of the neocortex to be removed in temporal lobe resection was based on anatomical and intra-operative cortical mapping findings. We present our results regarding speech preservation in patients submitted to CAH using the central artery as an anatomical landmark for determining the posterior border of neocortical resection. METHODS: Two hundred and fifty consecutive right-handed patients with left unilateral mesial sclerosis were studied. All patients were submitted to CAH under general anesthesia and without intraoperative electrocorticography. The posterior border of the lateral neocortical resection was defined by a line perpendicular to the temporal axis at the level of the central artery. RESULTS: Seven patients had transient (1-3 weeks; mean=9 days) receptive speech disturbance. There was no permanent speech deficit. Imaging documented edema or contusion at the posterior temporal cortical border in all patients who had transient speech deficits. The mean extent of cortical resection was 3.9 cm in adults and 3.1cm in kids. DISCUSSION: This is the first report in the literature discussing the use of a non-linear paradigm to determine the extent of lateral neocortical removal in this patient population. We found no permanent speech disturbances in this series. The non-linear approach used in this series proved to be safe and effective to avoid post-operative speech disorders. It was able to compensate for different brain and head sizes, and allowed smaller neocortical removal when compared to traditional linear approaches.

Intraoperative neurophysiological responses in epileptic patients submitted to hippocampal and thalamic deep brain stimulation.

PURPOSE: Deep brain stimulation (DBS) has been used in an increasing frequency for treatment of refractory epilepsy. Acute deep brain macrostimulation intraoperative findings were sparsely published in the literature. We report on our intraoperative macrostimulation findings during thalamic and hippocampal DBS implantation. METHODS: Eighteen patients were studied. All patients underwent routine pre-operative evaluation that included clinical history, neurological examination, interictal and ictal EEG, high resolution 1.5T MRI and neuropsychological testing. Six patients with temporal lobe epilepsy were submitted to hippocampal DBS (Hip-DBS); 6 patients with focal epilepsy were submitted to anterior thalamic nucleus DBS (AN-DBS) and 6 patients with generalized epilepsy were submitted to centro-median thalamic nucleus DBS (CM-DBS). Age ranged from 9 to 40 years (11 males). All patients were submitted to bilateral quadripolar DBS electrode implantation in a single procedure, under general anesthesia, and intraoperative scalp EEG monitoring. Final electrode's position was checked postoperatively using volumetric CT scanning. Bipolar stimulation using the more proximal and distal electrodes was performed. Final standard stimulation parameters were 6Hz, 4V, 300µs (low frequency range: LF) or 130Hz, 4V, 300µs (high frequency range: HF). KEY FINDINGS: Bilateral recruiting response (RR) was obtained after unilateral stimulation in all patients submitted to AN and CM-DBS using LF stimulation. RR was widespread but prevailed over the fronto-temporal region bilaterally, and over the stimulated hemisphere. HF stimulation led to background slowing and a DC shift. The mean voltage for the appearance of RR was 4V (CM) and 3V (AN). CM and AN-DBS did not alter inter-ictal spiking frequency or morphology. RR obtained after LF Hip-DBS was restricted to the stimulated temporal lobe and no contralateral activation was noted. HF stimulation yielded no visually recognizable EEG modification. Mean intensity for initial appearance of RR was 3V. In 5 of the 6 patients submitted to Hip-DBS, an increase in inter-ictal spiking was noted unilaterally immediately after electrode insertion. Intraoperative LF stimulation did not modify temporal lobe spiking; on the other hand, HF was effective in abolishing inter-ictal spiking in 4 of the 6 patients studied. There was no immediate morbidity or mortality in this series. SIGNIFICANCE: Macrostimulation might be used to confirm that the hardware was working properly. There was no typical RR derived from each studied thalamic nuclei after LF stimulation. On the other hand, absence of such RRs was highly suggestive of hardware malfunction or inadequate targeting. Thalamic-DBS (Th-DBS) RR was always bilateral after unilateral stimulation, although they somehow prevailed over the stimulated hemisphere. Contrary to Th-DBS, Hip-DBS gave rise to localized RR over the ipsolateral temporal neocortex, and absence of this response might very likely be related to inadequate targeting or hardware failure. Increased spiking was seen over temporal neocortex during hippocampal electrode insertion; this might point to the more epileptogenic hippocampal region in each individual patient. We did not notice any intraoperative response difference among patients with temporal lobe epilepsy with or without MTS. The relationship between these intraoperative findings and seizure outcome is not yet clear and should be further evaluated.

Outcome after cortico-amygdalo-hippocampectomy in patients with temporal lobe epilepsy and normal MRI.

RATIONALE: We describe seizure and neuropsychological outcome obtained after CAH in patients with TLE and normal MRI evaluated in the modern imaging era. METHODS: Forty-five adult consecutive patients with TLE and normal MRI were studied. All patients had neuropsychological testing, interictal and ictal EEG recordings and MRI. They were divided into two groups: Group 1 (n=18), included patients in whom non-invasive neurophysiological evaluation was lateralizing and Group 2 (n=27) included patients with non-lateralizing neurophysiological data who were submitted to invasive recordings. RESULTS: Seventy-seven percent of the Group 1 patients were rated as Engel I; 11% were rated as Engel II and 11% as Engel III. In Group 2, there were 57% of patients seizure-free, 26% in Engel II and 14% in Engel III. Pre-operatively, mean general IQ was 82 and 78 in Groups 1 and 2, respectively; post-operatively, mean general IQ was respectively 86 and 71. Some degree of verbal memory decline was noted in all patients submitted to dominant temporal lobe resection in both Groups 1 and 2. At last follow-up visit, 22% of Group 1 and 11% of Group 2 patients were receiving no antiepileptic drugs (AED). CONCLUSIONS: Our data showed that patients with TLE and normal MRI could get good surgical results after CAH although 60% of them would need invasive recordings and their results regarding seizure control and cognition were worse than those obtained in patients with MRI defined temporal lobe lesions. Caution should be taken in offering dominant temporal lobe resection to this subset of patients.

Outcome after cortico-amygdalo-hippocampectomy in patients with severe bilateral mesial temporal sclerosis submitted to invasive recording.

INTRODUCTION: Although some degree of bilateral hippocampal involvement might be frequent in patients with temporal lobe epilepsy, severe bilateral mesial temporal sclerosis (MTS) is very rare. We present our experience while treating patients with severe bilateral MTS submitted to invasive recordings. METHODS: Nine adult patients were studied. All patients had simple and complex partial seizures. All patients had bilateral independent interictal temporal lobe spiking and non-lateralizing video-EEG findings. MRI showed severe bilateral MTS and no other brain lesion. All patients had severe verbal and non-verbal memory deficits. All patients were submitted to invasive recordings after bilateral subdural grids implantation. Cortico-amygdalo-hippocampectomy (CAH) was performed in all patients on the side suggested by invasive recording. Follow-up time ranged from 5 to 10 years. RESULTS: Invasive video-EEG showed exclusively unilateral seizure onset in seven patients; in two patients, seizures originating from both temporal lobes were found (80% of them originated from one side). Five patients were submitted to left and four to right CAH. Seven patients were rendered seizure-free after surgery (Engel I); the other two were rated as Engel II. There was no additional memory decline. There was no surgical morbidity or mortality. Pathological examination showed MTS in all patients. DISCUSSION: 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.

Centro-median stimulation yields additional seizure frequency and attention improvement in patients previously submitted to callosotomy.

RATIONALE: Deep brain stimulation (DBS) has been increasingly used in the treatment of refractory epilepsy over the last decade. We report on the outcome after thalamic centro-median (CM) DBS in patients with generalized epilepsy who had been previously treated with extended callosal section. METHODS: Four consecutive patients with generalized epilepsy who were previously submitted to callosal section and had at least 1 year of follow-up after deep brain implantation were studied. Age ranged from 19 to 44 years. All patients were submitted to bilateral CM thalamic DBS. Post-operative CT scans documented the electrode position in all patients. All patients had pre- and post-stimulation prolonged interictal scalp EEG recordings, including spike counts. Attention level was evaluated by means of the SNAP-IV questionnaire. The pre-implantation anti-epileptic drug regimen was maintained post-operatively in all patients. RESULTS: Post-operative CT documented that all electrodes were correctly located. There was no morbidity or mortality. Seizure frequency reduction ranging from 65 to 95% and increased attention level was seen in all patients. Interictal spiking frequency was reduced from 25 to 95%, but their morphology remained the same. There was re-synchronization of interictal discharges during slow-wave sleep in 2 patients. CONCLUSION: All patients benefit from the procedure. The CM seems to play a role in modulating the epileptic discharges and attention in these patients. On the other hand, it is not the generator of the epileptic abnormality and appeared not to be involved in non-REM sleep-related interictal spiking modulation.

Extended, one-stage callosal section for treatment of refractory secondarily generalized epilepsy in patients with Lennox-Gastaut and Lennox-like syndromes.

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 > or =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.

Surgical outcome in patients with refractory epilepsy associated to MRI-defined unilateral mesial temporal sclerosis

INTRODUÇÃO: Protocolos diferentes têm sido utilizados para a investigação pré-operatória de pacientes epilépticos nos diferentes centros. No entanto, o valor relativo de cada teste disponível ainda é controverso na literatura.OBJETIVO: Relatamos os resultados cirúrgicos de pacientes com epilepsia refratária do lobo temporal associada a esclerose hipocampal (EH), cuja investigação pré-operatória consistiu exclusivamente de estudo de eletrencefalograma (EEG) inter-crítico e ressonância magnética (RM). MÉTODO: Foram estudados 41 pacientes com epilepsia refratária do lobo temporal, avaliados pré-operatoriamente somente por meio de EEG interictal e RM encefálica. Foram incluídos somente pacientes em quem a RM mostrava apenas EH unilateral. Todos pacientes possuíam ao menos quatro EEG inter-ictais. Todos os pacientes foram submetidos a córtico-amígdalo-hipocampectomia no lado demonstrado pela RM.RESULTADOS: A análise do EEG interictal revelou atividade epileptiforme unilateral, compatível com os achados da RM em 37 pacientes. Nos outros quatro pacientes, o EEG evidenciou comprometimento bilateral. O tempo médio de seguimento pós-operatório dos pacientes foi 4,3±1,1 anos. No período pós-operatório, 95,1% dos pacientes encontravam-se em classe I de Engel (70,6% em Engel I-A) e 4.9% em classe II de Engel. Todos os pacientes com achados bilaterais ao EEG estavam em classe I de Engel. O estudo anátomo-patológico das amostras cirúrgicas revelou EH em todos os pacientes. CONCLUSÃO: É possível selecionar bons candidatos à ressecção temporal utilizando-se apenas dados de RM e EEG inter-ictal. Nos pacientes com EH unilateral na RM, espera-se um índice de remissão pós-operatória das crises superior a 90%. O achado de EH na RM é, isoladamente, o maior fator indicativo de bom prognóstico após ressecção temporal.

Insular epilepsy: similarities to temporal lobe epilepsy - case report

Insular epilepsy has been rarely reported and its clinical and electrographic feactures are poorly understood. The electrographic study of the insula is difficult since it is hidden from the brain surface by the frontal and temporal lobe. A 48 years-old woman started having simple partial autonomic and complex partial seizures with automatisms and ictal left arm paresis 8 years prior to admission. Seizure's frequency was 1 per week. Pre-operative EEG showed a right temporal lobe focus. Neuropsychological testing disclosed right fronto-temporal dysfunction. MRI showed a right anterior insular cavernous angioma. Intraoperative ECoG obtained after spliting of the sylvian fissure showed independent spiking from the insula and temporal lobe and insular spikes that spread to the temporal lobe. The cavernous angioma and the surrounding gliotic tissue were removed and the temporal lobe was left in place. Post-resection ECoG still disclosed independent temporal and insular spiking with a lower frequency. The patient has been seizure-free since surgery. Insular epilepsy may share many clinical and electroencephalographic features with temporal lobe epilepsy.

Qualidade de vida de pacientes submetidos a cirurgia de epilepsia / Quality of life of patients after epilepsy surgery

Epilepsia refratária ao tratamento medicamentoso é condiçao que interfere direta e negativamente na qualidade de vida dos pacientes, dificultando-lhes principalmente a integraçao social. O tratamento cirúrgico tem se mostrado eficaz no controle das crises em casos refratários, ocupando lugar importante no tratamento das epilepsias. Avaliamos a qualidade de vida de pacientes epilépticos, antes e após o tratamento cirúrgico, através de um questionário sobre qualidade de vida, adaptado do QOLIE-10 aplicado em 12 indivíduos epilépticos adultos, operados consecutivamente. O questionário, com 10 perguntas, envolvendo aspectos psicossociais e relacionados às drogas antiepilépticas, foi respondido no período pré-cirúrgico e repetido num intervalo médio de 8 meses após a cirurgia. Na comparaçao do questionário no período pré-operatório com o período pós-operatório, observamos diferenças estatisticamente significantes em 70 por cento das perguntas, mostrando melhora da qualidade de vida após a cirurgia. Nestes casos, a terapêutica cirúrgica tem forte impacto na qualidade de vida.

Secondary bilateral synchrony due to front-mesial lesions: an invasive recording study

Frontal lobe epilepsies may present difficulties in focus localization in the pre-operative work-up for epilepsy surgery. This is specially treu in patients with normal MRIs. We report on a 16 years-old girl that started with seizures by the age of 8 years. They were brief nocturnal episodes with automatisms such as bicycling and boxing. Seizure frequency ranged from 4-10 per night. Scalp EEG showed few right frontal convexity spiking and intense secondary bilateral syncrhony (SBS). High resolution MRI directed to the frontal lobes was normal. Ictal SPECT suggested a right fronto-lateral focus. Ictal video-EEG showed no focal onset. She was submitted to invasive recordings after subdural plates implantation. Electrodes covered all the frontal convexity and mesial surface bilaterally. Ictal recordings disclosed stereotyped seizures starting from the right mesial frontal. Using a high-resolution tool to measure intra and interhemispheric latencies, the timing and direction of seizure spread from the right fronto-mesial region were studied. Motor strip mapping was performed by means of electrial simulation. She was submitted to a right frontal lobe resection, 1,5 cm ahead of the motor strip and has been seizure free since surgery (8 months). Pathological examination found a 4 mm area of cortical dysplasia. Invasive studies are needed to allow adequate localization in patients with non-localizatory non-invasive work-up and may lead to excellent results in relation to seizures after surgery.