Estimulación crónica intermitente del nervio vago en el tratamiento de epilepsia refractaria: experiencia en México con 35 casos / Chronic intermittent vagal nerve stimulation in the treatment of refractory epilepsy: experience in Mexico with 35 cases

Introducción: El papel de la estimulación crónica intermitente del nervio vago (ECINV) en el tratamiento de la epilepsia refractaria está evolucionando y requiere precisarse mediante la descripción de resultados, efectos adversos y complicaciones en poblaciones específicas. Material y métodos: Se seleccionaron los pacientes con epilepsia refractaria sometidos a ECINV con mínimo 12 meses de seguimiento, utilizando estadística descriptiva e inferencial para valorar el efecto sobre la frecuencia e intensidad de las crisis, memoria, ánimo, estado de alerta, recuperación postictal y calidad de vida (escala subjetiva, cuestionario QoLIE-31), y los factores (sexo, edad, tiempo de evolución, número/tipo crisis, parámetros de estimulación) asociados a la respuesta clínica. Se describen los parámetros de estimulación usados, empleo del magneto, complicaciones y efectos adversos. Resultados: Se seleccionaron 35 pacientes, edad de cinco a 48 años, 18 con epilepsia parcial, 17 con generalizada. No hubo complicaciones, infección o alteración de la cicatrización en los procedimientos quirúrgicos. La reducción promedio en crisis fue de 55.65 % (p < 0.001). En epilepsias generalizadas hubo 58.8 % de respondedores y 88.9 % en parciales. Cuatro sujetos presentaron mejoría > 90 %, con control total; en dos pacientes aumentó la frecuencia de las crisis. La respuesta al tratamiento fue buena subjetivamente en 33 pacientes. La calificación global de QoLIE-31 aumentó 12.6 puntos (p = 0.020). Solo el tipo de crisis se asoció con la respuesta clínica. Los efectos adversos fueron transitorios y respondieron al cambio de parámetros de estimulación. Conclusiones: la ECINV es segura, bien tolerada y eficaz para el tratamiento paliativo en casos seleccionados de crisis parciales y generalizadas multifocales refractarias.

BACKGROUND: The role of vagal nerve stimulation (VNS) in the treatment of refractory epilepsy is still evolving and requires precision through extensive description of acute and chronic results, adverse effects and complications in specific populations. METHODS: We selected patients with refractory epilepsy subjected to VNS who had completed at least a 12-month followup. Descriptive and inferential statistics were used to review and assess the effects of VNS on seizure frequency/intensity, memory, alertness, mood, postictal recovery, and quality of life (subjective scale, QoL IE-31 inventory) as well as factors (gender, age, age of onset, time of surgery, stimulation parameters, seizure frequency and type) associated with clinical response. We describe stimulation parameters, complications and adverse effects compared to other series. RESULTS: We selected 35 patients with an age range of 5-48 years; 18 patients presented partial epilepsy and 17 generalized epilepsy. All procedures and wound healing were uneventful, and no infections were reported. Median reduction in seizure frequency was 55.65% (p <0.001). Four patients showed improvement of >90%. Two patients became seizure free, whereas seizure frequency increased in two patients. The subjectively qualified response to treatment was good in 33 patients. The mean global increase in the QoLIE-31 Scale was 12.6 (p = 0.020). Improvements in memory, mood, alertness and postictal recovery period were documented. Only seizure type showed statistically significant association with clinical response. Adverse effects were transitory and responded to changes in stimulation parameters. CONCLUSIONS: VNS is a safe, feasible, well-tolerated and effective palliative treatment in appropriately selected cases of refractory partial and multifocal generalized seizures.

Epilepsy in children: an epidemiological study at Kathmandu Medical College Teaching Hospital Kathmandu.

OBJECTIVES: To analyze the relative frequencies of various epileptic seizures and to study the age at onset of different seizure types in Nepalese children. DESIGN: Prospective study. SETTING: Hospital outpatient based in Kathmandu, Nepal, between November 2001 to October 2002. PARTICIPANTS: 50 children diagnosed as epilepsy excluding neonatal and febrile seizures. Main outcome measure: Diagnosis and classification of cases according to the International Classification of Epilepsy of the International League Against Epilepsy [ILAE] and number of patients in each category with various ages at first seizure. RESULT: Generalized seizures (78%) were 3.54 times commoner than partial seizures (22%). Most frequent seizure types were generalized tonic clonic (36%), tonic (16%), complex partial (14%), atonic (12%) and absence (10%). Generalized clonic, simple partial and partial with secondary generalization, each had less than 5% frequencies. In 40% cases the first seizure occurred when aged between 2-5 years. In partial seizures the peak age at onset was observed below 6 years while primary generalized seizure was more frequently seen in age group 2-10 years. CONCLUSION: More paediatric patients with primary generalized seizures (78%) were observed than with partial seizures (22%). In this age group, the most frequent seizure type was generalized tonic clonic (36%) with the peak frequency of age at onset of seizures in 2-5 years.