Intracranial video-EEG and surgery for focal atonic seizures.

Atonic seizures are epileptic attacks characterised by a sudden loss or diminution of muscle tone. Structures corresponding to inhibitory cortical areas, such as the primary negative motor area or the supplementary negative motor area, could be responsible. We present findings observed in a patient with atonic seizures due to focal epilepsy, who underwent intracranial video-EEG monitoring and epilepsy surgery, and discuss possible underlying mechanisms. [Published with video sequences].

Type II focal cortical dysplasia: electroclinical study and surgical outcome in 31 pediatric patients.

OBJECTIVE: The aim of this study was to analyze the electroclinical features and surgical outcome of 31 pediatric patients with focal cortical dysplasia (FCD) type II. MATERIAL AND METHODS: We conducted a retrospective, descriptive study of 31 patients with FCD type II followed between 1998 and 2011. We included patients with FCD type II confirmed by histopathological examination with abnormal magnetic resonance imaging and at least 1 year of follow-up. RESULTS: All patients had severe focal epilepsy; in infancy, four of them had also had epileptic spasms, associated with hypsarrhythmia in three. Focal status epilepticus occurred in five patients (16 %) and epilepsia partialis continua in one (3.2 %). Seizures occurred during sleep in 20 (64.5 %) and in clusters in 19 (61.3 %) patients. Neurological examination showed a mild motor deficit in seven (22.8 %) patients. Interictal abnormalities were characterized by rhythmic spikes and polyspike discharges, increasing during sleep in 13 (41.9 %) patients. Average time of follow-up after surgery was 4.7 years with a median time of 4 years and a range from 1 to 9 years. Engel classification class I was found in 20 (67.7 %) and class II in 3 cases (9.6 %). There were no significant changes after an average time of follow-up of 4.7 years. CONCLUSION: Our results confirm that surgery is the best treatment option for pediatric patients with refractory focal epilepsy due to type II FCD. A statistically significant correlation was found between a good prognosis and age at epilepsy onset older than 2 years.

Vagus nerve stimulation: effectiveness and tolerability in 64 paediatric patients with refractory epilepsies.

AIM: We discuss the effectiveness, tolerability, and safety of vagus nerve stimulation (VNS) as adjunctive therapy in 64 paediatric patients with refractory epilepsies. MATERIALS AND METHODS: Sixty-four patients (34 male and 30 female) implanted with VNS for refractory epilepsy were analysed. Electroclinical features were compatible with Lennox-Gastaut syndrome in 46 patients, focal epilepsies in 10 patients, Dravet syndrome in three patients, epilepsy with myoclonic-astatic seizures in three patients, and West syndrome in two. The NeuroCybernetic Prosthesis (NCP) system (Cyberonics, Webster, TX, USA) was employed and the following stimulation parameters were used: output current of 1 to 2.5mA, signal frequency of 30Hz, signal pulse width of 500µs, and signal "on" and "off" times of 30  seconds and 5  minutes, respectively. RESULTS: Of 46 patients with LGS, 30 cases showed a significant improvement in seizure control, with a reduction in seizure frequency of at least 50%. Ten patients with focal epilepsy, three patients with myoclonic-astatic seizures, two patients with Dravet, and two patients with West showed a significant improvement in seizure control, with a reduction in seizure frequency of at least 50%. A good clinical response was evident early and efficacy progressively improved with the duration of treatment up to 36 months. In a significant number of patients, reduced seizure severity and shorter recovery time and hospital stay were also observed. VNS was well tolerated in all patients. CONCLUSION: VNS is an effective and well-tolerated treatment for paediatric patients with refractory epilepsies, improving quality of life and neuropsychological performance.

Hemispherectomy in pediatric patients with epilepsy: a study of 45 cases with special emphasis on epileptic syndromes.

OBJECTIVE: In this study we report the clinical outcomes of hemispherectomy for epilepsy in pediatric patients with special emphasis on the epileptic syndromes and their etiologies. MATERIAL AND METHODS: We retrospectively studied 45 patients with medically refractory epilepsy with hemispheric lesions who underwent hemispherectomy at the "Hospital de Pediatría Prof. Dr. Juan P. Garrahan", Buenos Aires, Argentina between February 1990 and February 2010. Patients had been assessed using a standard protocol involving clinical, neuroradiological, neurophysiological, and neuropsychological teams. RESULTS: Twenty-seven males and 18 females with a mean age of 8.5 years (range, 2 months to 18 years) who underwent epilepsy surgery for refractory epilepsy were assessed. The mean time of follow-up was 9.5 years (range, 1 to 16 years). The following epileptic syndromes were recognized: West syndrome in 15 patients (33.5%), Rasmussen syndrome in 13 (29%), focal symptomatic epilepsy in 8 (17.5%), startle epilepsy in 6 (13.5%), Lennox-Gastaut syndrome in 2 (5%), and continuous spikes and waves during slow sleep in 1 (2%). The surgical specimens revealed malformations of cortical development in 18 patients (40%), Rasmussen encephalitis in 13 (29%), porencephalic lesions in 10 (22%), gliosis in 2 (4.4%), tumor in 1 (2.2%), and Sturge-Weber syndrome in 1 (2.2%). CONCLUSION: The outcome of hemispherectomy in pediatric patients is good for those with refractory epilepsies, such as West syndrome, Lennox-Gastaut syndrome, epileptic encephalopathy with continuous spikes and waves during slow sleep, and startle epilepsy arising from a hemispheric lesion associated with hemiplegia.

Vagus nerve stimulation: effectiveness and tolerability in patients with epileptic encephalopathies.

PURPOSE: We discuss the effectiveness, tolerability, and safety of vagus nerve stimulation (VNS) as adjunctive therapy in 26 patients with refractory epileptic encephalopathies (EEs). MATERIAL AND METHODS: Twenty-six patients (17 male and 9 female) with electroclinical features compatible with Lennox-Gastaut syndrome (LGS) in 20 patients, Dravet syndrome (DS) in 3 patients, and epilepsy with myoclonic-astatic seizures (EMAS) in 3 patients implanted with the NCP system were analyzed. RESULTS: In our series of patients with LGS, 17 cases showed a significant improvement in seizure control, with a reduction in seizure frequency of at least 50%. Seven of them previously had epileptic spasms. Three patients with EMAS and two patients with DS showed a significant improvement in seizure control, with a reduction in seizure frequency of at least 50%. A good clinical response was evident early and efficacy progressively improved with the duration of treatment up to 36 months. In patients who had a reduction in seizure frequency of at least 50%, quality of life (QOL) and neuropsychological performance improved. VNS was well-tolerated in all patients. CONCLUSION: VNS is an effective and well-tolerated treatment for patients with epileptic encephalopathies EEs, improving QOL and neuropsychological performance.

New proteins configure a brain drug resistance map in tuberous sclerosis.

Epileptogenic cortical tubers, characterized by dysplastic neurons and balloon cells, is a frequent feature of tuberous sclerosis. In severe tuberous sclerosis-affected individuals, seizures are refractory to medication. Multidrug resistance proteins (multidrug resistance protein-1 [MDR-1] and multidrug resistance-associated protein-1 [MRP-1]) have been found to be highly expressed in epileptogenic cortical tubers. However, two new proteins related to refractoriness in cancer (breast cancer resistance protein and major vault protein) have not been investigated in tuberous sclerosis and refractory epilepsy. On the same brain specimens previously describing the MDR-1 and MRP-1 expression, we investigated retrospectively breast cancer resistance protein and major vault protein by specific monoclonal antibodies and routine immunohistochemistry methods. Breast cancer resistance protein was present in vascular endothelial cells from all the vessels examined in 3 of 3 cases. Major vault protein was detected in only one case, and selectively expressed in several but not all ballooned cells. In epileptogenic cortical tubers, the additional expression of breast cancer resistance protein on vessels and major vault protein in some ballooned cells to the previously demonstrated expression of MDR-1 and MRP-1 (in vessels, astroglia, microglia, neurons, and ballooned cells) configures a brain protein pharmacoresistance map from patients with tuberous sclerosis and refractory epilepsy.

Multidrug resistance proteins in tuberous sclerosis and refractory epilepsy.

Tuberous sclerosis is an autosomal dominant syndrome characterized by seizures that are refractory to medication in severely affected individuals. The mechanism involved in drug resistance in tuberous sclerosis is unknown. The proteins MDR-1 (multidrug resistance) and MRP-1 (multidrug resistance-associated protein-1) are linked to chemotherapy resistance in tumor cells. However, the relationship between refractoriness to antiepileptic drugs and MDR-1 or MRP-1 brain expression has been poorly studied. We have previously described a case of tuberous sclerosis with refractory epilepsy that expressed multidrug resistance gene (MDR-1) in tuber cells from epileptogenic brain lesion. In this retrospective study, we describe the expression of MDR-1 and MRP-1 in the epileptogenic cortical tubers of three pediatric patients with tuberous sclerosis and refractory epilepsy surgically treated. Monoclonal antibodies for MDR-1 and MRP-1 proteins were used for immunohistochemistry. In epileptogenic cortical tuber brain specimens, MDR-1 and MRP-1 proteins were strongly immunoreactive in abnormal balloon cells, dysplastic neurons, astrocytes, microglial cells, and some blood-brain vessels. A more extensive MDR-1 immunoreactivity was observed. These data suggest that refractory epilepsy phenotype in tuberous sclerosis can be associated with the expression of both multidrug resistance MDR-1 and MRP-1 transporters in epileptogenic cortical tubers.

Symptomatic supratentorial arachnoid cysts in children.

This study was undertaken to evaluate the clinical and radiologic long-term outcome of symptomatic primary arachnoid cysts in pediatric patients. Thirty-three children, ranging from 2 months to 17 years of age (mean age, 6 years) were treated. Craniotomy and fenestration of the cyst were used for temporal fossa and midline cysts in 24 patients (73%); later, two patients required shunt placement. Shunting device implantation was performed for cerebral convexity cysts in nine patients (27%), and two patients required a subsequent craniotomy and fenestration of the cyst. Four patients (12%) required additional surgery because of clinical progression rather than for cyst enlargement. Eleven patients (33%) experienced a cyst reduction of more than 50% compared with the original size on imaging studies. There was a significant correlation with the alleviation of symptoms (P < 0.005), regardless of the treatment used. Complete alleviation of symptoms was achieved in all patients after treatment, regardless of cyst reduction. Long-term follow-up of 70 +/- 9.3 months demonstrated no recurrence of symptoms or progressive enlargement of the arachnoid cyst in all children.

Mesial temporal lobe epilepsy with hippocampal sclerosis: study of 42 children.

PURPOSE: We present the electroclinical features, treatment, and evolution of patients with mesial temporal lobe epilepsy with hippocampal sclerosis (MTLE-HS). MATERIAL AND METHODS: We analyzed the charts of forty-two patients who met the diagnostic criteria of MTLE-HS. The mean follow-up after seizure onset was 10.5 years. RESULTS: According to age, we defined three groups. The first group included nine patients that started with seizures before 2 years of age. Motor seizures were the hallmark clinical manifestation. All patients of this group also presented with motor arrest and oro-alimentary automatisms. In three of them, the interictal EEG recordings showed bilateral paroxysms predominantly in anterior regions, in addition to focal abnormalities, and two had an apparently generalized ictal pattern. The second group included 17 patients that started with seizures between 2 and 10 years of age. In this group the automatisms were also oroalimentary, but more complex and the patients had less motor manifestations. The interictal EEG recordings showed temporal abnormalities. The ictal EEG recordings showed lateralized abnormalities with a maximum in the temporal electrodes. The third group included 16 patients that started with seizures between 10 and 16 years of age. The most common clinical manifestation was abdominal aura followed by oroalimentary, gestural, and verbal automatisms. The interictal and ictal EEG recordings showed well-localized abnormalities in temporal lobes. Thirty-eight patients underwent surgical treatment. Thirty-five patients are seizure free. CONCLUSION: MTLE-HS represents a well-defined and distinct symptomatic epileptic syndrome. Surgical treatment was successful in most patients.

Inclusión de técnicas imagenológicas en la planificación neuroquirúrgica: integración de equipos multidisciplinarios / Inclusion of imaging techniques in neurosurgical planning: integration of multidisciplinary teams

Introducción: El tratamiento quirúrgico de las epilepsias consiste en lograr la resección del área lesional o epileptógena minimizando a la vez el déficit neurológico postquirúrgico. Las neuroimágenes se han constituido en una poderosa herramienta diagnóstica. El procesamiento de las mismas logran proveer relación topográfica entre la lesión, el área epileptogénica primaria y las áreas funcionales importantes de manera no invasiva. Objetivos: Estudiar la utilidad de incluir diferentes técnicas de imágenes en la evaluación prequirúrgica, planificación y resección quirúrgica de epilepsias. Materiales y Métodos: Se estudiaron 8 pacientes con diagnóstico de epilepsia con diversas técnicas imagenológicas, en resonador 3T y en tomógrafo helicoidal de 64 canales. Las imágenes fueron post-procesadas, corregistradas, fusionadas e incorporadas en el sistema de neuronavegación. La información resultante fue estudiada por un equipo multidisciplinario de físicos médicos y neurocirujanos. Resultados: Los casos presentados muestran que la incorporación e integración de las técnicas de imágenes facilitan la comprensión anatómica, metabólica y funcional del área lesional /epileptogénica y el tejido circundante. La cirugía guiada por imágenes colabora en la mejora de las limitaciones de los métodos “gold standard”, como son la electrocorticografía y la estimulación cortical eléctrica directa, disminuyendo la invasividad, el tamaño de la craneotomía, aumentando el área de resección de la lesión y brindando mayor seguridad en los resultados postquirúrgicos.

Epilepsy surgery in Argentina: long-term results in a comprehensive epilepsy centre.

RATIONALE: Epilepsy surgery procedures started in Argentina more than 50 years ago. This is the first comprehensive and systematic survey of epilepsy surgery long-term outcome from our country. METHODS: A descriptive cohort study was conducted between 1998 and 2008 for drug-resistant epilepsy surgery with a minimum of 12 months follow-up (n=110). In 84 cases (76.36%) resective surgery was performed, and outcome periodically assessed using the Engel score. Patients were stratified into groups: 12, 13-36, 37-60 and over than 60 months of follow-up. Video-EEG with and without intracranial electrode implants, intraoperative electrocorticograms, Wada tests, pathology reports, use of antiepileptic drugs (AEDs), and surgical complication rates were evaluated. RESULTS: Surgical techniques included: 69 lobectomies (62.7%), 15 lesionectomies (13.6%), 6 callosotomies (5.4%), 6 multiple subpial transection (5.4%), 11 vagus nerve stimulations (10%), 3 hemispherectomies (2.7%). Male: female ratio: 1/1.44. Mean age at time of surgery: 26.2 years. Mean duration of epilepsy: 14 years. Age at seizure onset: 11.5 years. Mean follow-up: 46 months. Pathology findings: mesial temporal sclerosis 32 (35.1%); dual pathology 17 (18.7%); cortical dysplasia 15 (16.4%); non-specific inflammatory changes 11 (12.1%); tumors 7 (7.7%); other 6 (6.8%). Engel scores at 12 months follow-up: 72.6% (61) class I, 16.6% (14) class II and 15.5% (13) class III-IV; 13-36 months after surgery: 68.1% of cases were class I, 15.9% class II and 15.5% class III-IV. After 37-60 months, 74% class I, 14% class II, 14% class III-IV. Over 60 months (n=45) 78% class I, 13.5% class II and 8.1% class III-IV. CONCLUSION: Conducting a successful epilepsy surgery program in a developing country is challenging. These results should encourage specialists in these countries. Long-term outcome results comparable to centres in developed countries can be achieved.

Utilidad del PET en la epilepsia no lesional del lóbulo temporal / Usefulnes of PET scan in non-lesional related temporal lobe epilepsy

Objective: to evaluate the usefulness of PET in patients with refractory non-lesional temporal lobe epilepsy. Material and methods: we present three patients with features of temporal lobe epilepsy refractory to medication, where highdefinition MRI was normal. Results: these patients had PET hypometabolism in the temporal areas related to clinical and neurophysiological findings. Two of these patients were implanted with subdural grids to confirm the diagnosis and the third was operated directly based on the findings of PET. Encourage the presentation of the importance in recent years is acquiring the PET. Conclusion: in those patients in clinical neurophysiology and epilepsy with suspected temporal lobe, but in the MRI images show no structural lesions, PET can play an important role defining the diagnosis.

Use of ultrasonic aspiration for dural opening in cranial reoperations: technical note.

OBJECTIVE: Dural detachment from the brain in cranial reoperations has been accomplished previously by selective coagulation and the cutting of brain-dural adhesions. The results of ultrasonic aspiration during tumor surgery or brain cutting procedures led the authors to speculate that the detachment of the dura mater from brain tumors by applying the Cavitron ultrasonic surgical aspirator (Valleylab, Boulder, CO [formerly Cavitron, Inc., Stamford, CT]) to the brain-dura mater interface could be used to reduce bleeding and facilitate dural opening during cranial reoperations. METHODS: Ten patients underwent a second craniotomy for epilepsy surgery (five cases of extended temporal lobectomy and five cases of extended extratemporal lesionectomy). The use of ultrasonic aspiration and its effects on brain separation from the dura mater were examined. RESULTS: Intraoperative use of the Cavitron ultrasonic surgical aspirator during dural opening produced immediate blanching of the dura mater and enhanced visualization of the cortical surface without distortion of the brain anatomy. CONCLUSION: Incremental dural opening and brain visualization is achieved by careful application of ultrasonic aspiration directly into the brain-dura limit, producing immediate regional dural devascularization. Use of this technique reduces cortical and dural bleeding and enhances the ease and effectiveness of brain visualization.

Patología de las malformaciones del desarrollo cortical en pacientes con epilepsia refractaria: experiencia en un hospital pediátrico / Pathology of CDM in patients with refractory epilepsy: experience in a pediatric hospital

Las malformaciones del desarrollo cortical (MDC) comprenden un grupo heterogéneo de lesiones caracterizadas por una desorganización de la arquitectura normal de la corteza cerebral, que incluye desde cambios microscópicos sutiles a extensas lesiones que pueden comprometer un hemisferio entero o conformar síndromes genéticos definidos. Múltiples esquemas de clasificación han sido propuestos para catalogar pacientes con malformaciones del desarrollo en subgrupos, basados en criterios de imágenes y hallazgos patológicos. Sin embargo aun hoy, la bibliografía es muy confusa en cuanto a su nomenclatura y/o a los criterios utilizados para evaluar la reproducibilidad. En algunos casos puede ser difícil distinguir estas lesiones de un tumor (ganglioglioma o Tumor Neuroepitelial Disembrioplásico) por la posible coexistencia de ambas lesiones y la representatividad de las muestras. La utilización del tejido humano de las resecciones quirúrgicas provee una fundamental herramienta tanto para esclarecer la patogénesis como para futuras investigaciones. Nuestra experiencia en patología de la epilepsia relacionada con malformaciones del desarrollo a lo largo de 20 años en un hospital público pediátrico incluye patología del lóbulo temporal y extratemporal, con lesiones puras malformativas, patología dual y otras asociaciones.

Malformations of cortical development (MCD) comprise a heterogeneousgroup of lesions characterized by a disruption of the normal architecture of the cerebral cortex, ranging from subtlemicroscopic lesions to large lesions that can compromise an entire hemisphere or shape defined genetic syndromes. Multiple classification schemes have been proposed to catalogue patients with developmental malformations in subgroups based on criteria and pathological images. But even now, literature is very confusing in their classification and / or the criteria used to assess reproducibility. In some cases it may be difficult to distinguish these lesions from a tumor (ganglioglioma orDysembryoplastic Neuroepithelial Tumor) for the possible coexistenceof both lesions and representativeness of the samples. The use of human tissue for surgical resection provides afundamental tool both to clarify the pathogenesis and for future research. Our experience in pathology of epilepsy associated with malformations of the development over 20 years in a public pediatric hospital includes temporal lobe and extratemporal pathology, pure malformations, dual pathology and other associations.

Malformación del desarrollo cortical: nuestra experiencia acerca de 150 casos / Cortical development malformations (CDM): our experience on 150 cases

Objetivo Realizar una evaluación retrospectiva de 150 pacientes de una serie de 570 (26.3%), operados por epilepsia refractaria con diagnóstico de algún tipo de malformación del desarrollo cortical (MDC), desde 1988 a noviembre de 2009. Material y método. 118 niños y 32 adultos; 69 localización temporal (42 niños, 27 adultos) y 81 extratemporal (76 niños y 5 adultos). La evaluación prequirúrgica incluye: características clínico-semiológicas de las crisis epilépticas, EEG de superficie, video EEG, TC y/o RM y evaluación neuropsicológica. Población: varones: 86; mujeres 64; edad, media de 6.7 años (rango: 6 m – 18.9 a) en los niños y media de 31.3 años (rango: 19-59 a) en los adultos. Evolución de epilepsia: media de 4.9 años para los niños (rango: 1 mes a 17 años) y media de 13.8 (rango: 2 meses a 50 años). Aspectos clínicos: tipos de crisis: pudiendo un mismo paciente presentar más de una de ellas, vinculadas a la localización, CPS, ausencias, crisis tónicas, automatismos, crisis versivas, CPC, anopsia transitoria, “drop attacks”, “Startle epilepsia”, escotoma, automatismos masticatorios, crisis clónicas, fotopsia, desviación ocular, “head attacks”. Imágenes: la TC fue normal en 5, y se realizó IRM en todos a partir de 1996

Objective: To evaluate the surgical results in a group of patients with epilepsy associated with cortical development malformations (CDM). Method: A retrospective study in 150 patients of a series of 570 patients (26.3%) who have undergone surgery for intractable epilepsy with a diagnosis of CDM, since 1988. Clinical features,scalp EEG, video EEG, CT scan, MRI and neuropsychological evaluation were assessed. Population: males: 86 patients, females: 64; mean age, children: 6.7 years (range: 0,5-18.9) and adults: 31.3 years (range: 19-59); mean evolution of epilepsy, children: 4.9 years (range: 1mo-17 yr.), adults: 13.8 years (range: 2mo-50 yr.). Clinical manifestations: CPS, absences,tonic crises, automatisms and versive crises, CPS, transitory anopsia, drop attacks and Startle epilepsy, scotoma, masticatory automatisms, clonic crises, photopsia, eye deviation and head attacks. Imaging: CT scan was normal in 5, and MRI was performed since 1996. Twenty of 150 (13.3%) required chronic intracranial electrodes implantation. Surgical procedures: resectives: lesionectomies 63 (wide lesionectomy, 17 and + MST, 5), standard anterior temporal lobectomies (SATL) 37, anteromesial resections (Spencer) 9, corticectomies 11(+MST, 1),amigdalo- hippocampectomies 3, anatomic hemispherectomy 1, lobectomy1 and polectomies 4; disconnecting procedures: functional hemispherectomies (FH) 10, hemispherotomy 4, hemi-hemispherectomy 1, multiple subpial transection (MST) 1 and 2 callosotomies...

Epilepsia refractaria del lobulo temporal secundaria a patología dual: Nuestra experiencia acerca de 32 casos / Refractory temporal lobe epilepsy secondary to dual pathology: Review of 32 cases

Classical dual pathology is the coexistence of temporal mesial sclerosis (TMS) and an ipsilateral extra-hippocampal lesion. The aim of this presentation is to increase the awareness of the existence of this pathology as well as variants as a cause of refractory temporal lobe epilepsy and its difficult pre-op diagnosis. Of the 32 cases here presented, 19 were adults and 13 children. Adults: 17 had TMS + cortical dysplasia (CD) and of the remaining patients, 1 had TMS + oligodendroglioma and 1 TMS+ ganglioglioma. Children: pathology findings were: A) TMS + malformation of cortical development 6; B) TMS + CD + ganglioglioma 2; TMS + ganglioglioma + post-infectious sequelae 1 (“triple pathology”) and C) CD associated with low-grade glioma 1 and with MAV 1.Surgical techniques: LATS and the Spencer variant were the most commonly used techniques. Results: Patients in both groups are in Engel Class I and II. Conclusion: The good results in this series can be attributed to the complete resection of these entities.

Resultados de la cirugía de epilepsia en esclerosis tuberosa / Results of surgical treatment of epilepsy in tuberous sclerosis patients

Objective. We review our experience with surgical treatment in tuberous sclerosis and refractory epilepsy. Method. Between june 1995 and june 2008 , surgery was performed in 12 patients with tuberous sclerosis and refractory epilepsy. Median age: 6 years (r=6 months-19 years). 6 males and 6 females. Epilepsy began during the first year of life. They have been studied with RMI and video-EEG. Two patients were studied with intracranial electrodes. Electrocorticography was performed in 7, somatosensory evoked potentials in 2 and cortical stimulation in 1. Epileptogenic region was frontal in 4, temporal in 3, parietal in 2, occipital in 1 and bilateral in 2. Surgical procedures were resection of the epileptogenic regions and associated tuber(s) in 6, temporal lobectomy in 1, callosotomy in 1, parietal lobectomy in 1, frontal polectomy and vagus nerve stimulation in 1. A second surgery was performed in 1 case. Results. The outcome of seizures was classified with Engel’s outcome classification: 7 patients were in class I , 2 in class II and III . Callosotomy and vagus nerve stimulation were performed in 2 patients who had multifocal abnormality , seizure freedom was achieved in more than 60%.

Hemisferectomías y hemi-hemisferectomías: nuestra experiencia acerca de 49 casos / Hemispherectomy and hemi-hemispherectomy: Review of 49 cases

Objective. To review the results of hemispherectomy in the treatment of refractive epilepsy. Methodology. Analytic retrospective cohort study including every patient presenting refractive epilepsy to pharmacologic therapy, operated with hemispherectomy techniques from 1988 to 2008 (n=49). Of 507 patients, operated for refractive epilepsy in the last 20 years, in 49 cases we used any kind of hemispherectomy techniques (9,7%). The male/female relationship was 1.13-1, with 53% males and 47% females. The mean age was 8±5 years old, minimum 4 months and maximum 19 years old. The epilepsy time evolution was 3±2 years. The age of initial presentation was 3±1 years old. The more frequent pathologies were: Rasmussen encephalopathy (30,6%) and secuelar lesions (34,7%). Results. The results were evaluated with the Engel score. Using this classification, our patients were distributed in this manner: 40 patients (81,6%) were in class I of Engel; 4 patients (8,2%) in class II of Engel and 5 patients (10,2%) en Engel III and IV. 88% (43 cases) without complications, 4% (2 cases) present hematomas and the same occur with hydrocephalus and postoperative meningitis. One patient died a few days posterior to surgery because of hematologic complications. Conclusion. The hemispherectomy for the management of refractive epilepsy is a safe procedure with high positive results and small morbimortality in selective pathologies.

Esclerosis temporal mesial: paradigma de la epilepsia de resolución quirúrgica / Mesial temporal sclerosis: paradigm of surgically treatable epilepsy

Objetivo. Describir la esclerosis temporal mesial (ETM) es sus aspectos anatómicos, fisiopatológico, clínico, imagenológico, neurofisiológico, neuropsicológico y quirúrgico; y su relación con la epilepsia de resolución quirúrgica. Luego analizar estadísticamente nuestra casuística y resultados. Materiales y métodos. De los 469 (115 adultos y 354 niños) pacientes intervenidos quirúrgicamente por presentar epilepsia entre los años 1989-2007 en el Hospital Dr. Juan P. Garraham, FLENI, Hospital Dr. Cosme Argerich y Hospital Prof. Dr. Rodolfo Rossi, se analizar 91 pacientes (19.4%) con el diagnóstico de ETM; 38 de los cuales (41.75%) son niños y 53 (58.25%) adultos. Resultados. Los resultados son evaluados mediante el score de Engel. Aplicando esta clasificación, nuestra población tiene la siguiente distribución; 69 pacientes (75.8%) se encuentran en clase IA de Engel, de ellos 36 son niños (52.2%) y 33 adultos (47.8%); 4 pacientes adultos se encuentran en Engel IB (4.4%), 3 en Engel IC (3.3%), 1 adulto en Engel ID (1.1%), 4 adultos en Engel IIA (4.4%), 5 adultos en Engel IIB (5.5%) y 3 pacientes en Engel IVA (3.3%) de ellos 1 niño a quien posteriormente se le implantó un estimulador del nervio vago y los 2 restantes adultos. Un paciente adulto se suicidó luego de un año de la cirugía (en clase IA de Engel). Un paciente se encuentra durante su primer año postoperatorio por lo cual no puede ser incluido aún en la estadística de resultados. Conclusión. La ETM es el paradigma de la epilepsia refractaria en al población adulta y la causa de un porcentaje significativo de pacientes pediátricos sometidos a cirugía. La evolución prequirúrgica debe ser exhaustiva para lograr la selección del paciente. La resección quirúrgica debe ser realizada con la mayor selectividad posible. El diagnóstico y tratamiento precoz permite lograr un alto índice de curación.