Stereotactic thermocoagulation for insular epilepsy: Lessons from successes and failures.

OBJECTIVE: To assess factors associated with favorable outcome in refractory insular epilepsy treated by volume-based stereotactic radiofrequency thermocoagulation (RFTC). METHODS: We performed volume-based RFTC in 19 patients (11 males, 7-44 years old). The volume for thermocoagulation was identified by multimodal data including electroencephalography (EEG)-video, magnetic resonance imaging (MRI), and fluorodeoxyglucose-positron emission tomography (PET) in all patients, and epileptogenic zone (EZ) was assessed by stereo-electroencephalography (SEEG) in 16. MRI showed insular lesions in four patients (benign tumors, n = 2; focal cortical dysplasia [FCD], n = 1; polymicrogyria, n = 1). MRI was negative in 15 cases; however, PET was positive in 18, and FCD pattern was detected by SEEG in nine cases. The dominant hemisphere was involved in 12 cases. RFTC was performed as a separate procedure after SEEG, or as a single MRI-guided procedure. The insular volume to be coagulated was determined by a tridimensional identification of the epileptogenic cortex using MRI, PET, and SEEG, and was destroyed with coalescent thermal lesions. RESULTS: Seizure-free outcome was achieved in 10 patients (53%), including Engel class IA in three (follow-up = 1-12 years, mean = 5.4). The responder rate (including Engel classes I-III) was 89%. Transient postoperative deficits (mild hemiparesia, dysarthria, hypoesthesia, dysgeusia) were observed in eight patients (42%), with rapid and total recovery in all but one with persistent mild dysarthria. Neurological deficits were related to higher number of RFTC procedures (P = .036) and greater volume of RFTC (P = .028). Neuropsychological status was unchanged or improved in all; however, psychiatric status transitorily worsened in three patients. Factors contributing to seizure-free outcome were the detection of FCD pattern (P = .009), localized EZ (P = .038), low RFTC volume (P = .002), low number of RFTC procedures (P = .001), and low RFTC volume/number ratio (P = .012). Optimal volume of RFTC around 2 cm3 offered the best compromise between efficacy and safety. SIGNIFICANCE: RFTC may be curative in insular epilepsy after accurate localization of EZ with SEEG. Best outcome was associated with low volume of thermolesions.

Epilepsia refratária: a experiência do Núcleo Avançado de Tratamento das Epilepsias do Hospital Felício Rocho (NATE) no período de março de 2003 a dezembro de 2006 / Refractory epilepsy: the experience of the NATE

INTRODUÇÃO: A epilepsia é um problema de saúde pública. Afeta mais de cinqüenta milhões de pessoas em todo mundo e mais de vinte milhões deles continuam apresentando crises que não controlam satisfatoriamente com o uso de medicamentos. As epilepsias refratárias correspondem a cerca de 20 por cento dos pacientes epilépticos e boa parte desses apresentam crises parciais complexas passíveis de tratamento cirúrgico. A indicação cirúrgica criteriosa tem se mostrado eficiente para o controle das crises. OBJETIVO: Apresentar dados epidemiológicos e cirúrgicos dos pacientes submetidos ao tratamento cirúrgico no NATE. METODOLOGIA: Estudo retrospectivo com análise de prontuários e classificação do controle de crises de 46 pacientes considerando a Escala de Engel. RESULTADOS: Predomina o sexo masculino, solteiros, sem história familiar para epilepsia. Pacientes procedentes do Estado de Minas Gerais e outros estados da união. Início das crises na infância para 58,8 por cento dos pacientes sendo o tipo de crise mais freqüente a crise parcial complexa. O déficit de memória foi a queixa cognitiva mais comum. CONCLUSÃO: O controle de crise foi compatível com Engel Ia (sem crise) para 67 por cento dos pacientes. O tratamento cirúrgico revelou-se eficiente para o controle das crises dos pacientes portadores de epilepsia refratária ao tratamento medicamentoso.

INTRODUCTION: Epilepsy is a health public problem. Afflicts more than 50 million people worldwide, and more than 20 million of those affected do not have satisfactory seizures control with medicine. The refractory epilepsy represents 20 percent of all epileptic patients and most of them present partial seizures which can be treated by surgical treatment. The careful surgical recommendation can be efficient to seizure control. PURPOSE: The aim of this study was to present epidemiological and surgical data about patients submitted to surgical treatment in NATE - Advanced Center of Epilepsy Treatment. METHOD: We used a retrospective assessment method and control seizure classification from Engel Scale for 46 epileptic patients submitted to surgical treatment. RESULTS: Our results showed predominant male patients, single, without family history for epilepsy. The patients were from cities of Minas Gerais State and from another States in Brazil. The first seizure occurred in the childhood for 58,8 percent of patients and the more frequent seizure type was complex partial seizure. The predominant cognitive complaint was about memory. CONCLUSION: The surgical treatment for seizure control was good for 67 percent of patients that display Engel Ia classification (without seizures) and has a high likelihood for success in medically intractable temporal lobe epilepsy.

Clinical correlates of periodic breathing in neonatal polysomnography.

OBJECTIVE: Periodic breathing is a respiratory pattern typical of preterm infants, but its clinical significance has not been clarified yet. The present study was designed to investigate whether the presence of periodic breathing is specifically associated to low post-conceptional ages, preterm birth, or common clinical disorders related to preterm birth. METHODS: The study included 271 consecutive infants submitted to neonatal polysomnography, of whom 138 were born before 37 complete gestational weeks (preterm) and 133 were full-term. The main outcome measure was periodic breathing. A multivariate analysis was performed to test the specific impact of preterm birth, respiratory distress syndrome and hypoxic-ischemic encephalopathy on the occurrence of periodic breathing, with adjustment for potential confounding factors such as the post-conceptional age by the time of the polysomnography. RESULTS: Periodic breathing was twice more frequent in infants born before term (83/138 [60%]) than in full-term babies (41/133 [31%], chi2 = 22.3, P < 0.0001). The presence of periodic breathing was not significantly associated to either hypoxic-ischemic encephalopathy or respiratory distress syndrome. After a multivariate analysis, only preterm birth remained in the regression model as a specific risk factor for periodic breathing (adjusted odds ratio=5.62, P < 0.0001). CONCLUSIONS: Periodic breathing is a respiratory pattern independently associated with preterm birth, and this association cannot be imputed to the coexistence of either respiratory distress syndrome or hypoxic-ischemic encephalopathy among preterm infants. SIGNIFICANCE: The finding of periodic breathing in neonatal polysomnography correlates with preterm birth but not with its associated clinical disorders.

Developmental characteristics of temporal sharp transients in the EEG of normal preterm and term newborns.

OBJECTIVE: To describe developmental characteristics, morphological aspects and incidence of temporal sharp transients (TST) in normal preterm and term newborns at matched conceptional ages (CA). METHOD: Neonatal EEGs from two groups of normal newborns were evaluated in order to identify and characterize TST. Group I (n=40) consisted of newborns from 34 to 40 weeks of gestational age (GA) that were submitted to a single EEG between 24 and 48 hours of life. Group II consisted of 10 preterm newborns with GA between 30-32 weeks, followed with a weekly EEG until they reached term. Morphology of TST was divided in 3 groups (temporal sawtooth, isolated transients or repetitive transients). TST index, density and total number were calculated in each polysomnography and related to sleep stages and CA. Laterality (right/left) was also evaluated. The groups were compared at 34, 36, 38 and 40 weeks of CA. RESULTS: TST index and density decreased with the increase of CA in both groups (p<0.0001). The temporal sawtooth feature was registered in both groups only at 34 weeks. Although rare, repetitive and isolated TST were the most prevalent morphology between 36 - 40 weeks CA. Significant intragroup difference was observed in the comparison of TST density in REM and transitional sleep in GI. Moreover, isolated TST morphology was significant higher in GI at 34 weeks when compared to the others CA. No intragroup differences were observed on GII. No significant differences between the groups were observed considering TST number, index, density, morphology or laterality, at the matched CA. CONCLUSION: TST are normal features of neonatal EEG, as they are registered in normal newborns. Its incidence varies accordingly to morphology and they tend to disappear following the increase of CA. Temporal sawtooth appears more often in preterm newborns. Our results suggest that TST index, density and morphology variability may be a function of CA.

Developmental characteristics of temporal sharp transients in the EEG of normal preterm and term newborns

OBJECTIVE: To describe developmental characteristics, morphological aspects and incidence of temporal sharp transients (TST) in normal preterm and term newborns at matched conceptional ages (CA). METHOD: Neonatal EEGs from two groups of normal newborns were evaluated in order to identify and characterize TST. Group I (n=40) consisted of newborns from 34 to 40 weeks of gestational age (GA) that were submitted to a single EEG between 24 and 48 hours of life. Group II consisted of 10 preterm newborns with GA between 30-32 weeks, followed with a weekly EEG until they reached term. Morphology of TST was divided in 3 groups (temporal sawtooth, isolated transients or repetitive transients). TST index, density and total number were calculated in each polysomnography and related to sleep stages and CA. Laterality (right/left) was also evaluated. The groups were compared at 34, 36, 38 and 40 weeks of CA. RESULTS: TST index and density decreased with the increase of CA in both groups (p<0.0001). The temporal sawtooth feature was registered in both groups only at 34 weeks. Although rare, repetitive and isolated TST were the most prevalent morphology between 36 - 40 weeks CA. Significant intragroup difference was observed in the comparison of TST density in REM and transitional sleep in GI. Moreover, isolated TST morphology was significant higher in GI at 34 weeks when compared to the others CA. No intragroup differences were observed on GII. No significant differences between the groups were observed considering TST number, index, density, morphology or laterality, at the matched CA. CONCLUSION: TST are normal features of neonatal EEG, as they are registered in normal newborns. Its incidence varies accordingly to morphology and they tend to disappear following the increase of CA. Temporal sawtooth appears more often in preterm newborns. Our results suggest that TST index, density and morphology variability may be a function of CA