Electroencephalography abnormalities in generalized epilepsy and their predictors: A multicenter experience

Background: In spite of the overwhelming significance of knowledge of basic elements of electroencephalography (EEG) in its application to the diagnostic workup and the management of patients with suspected or already established generalized epilepsy (GE), there is a dearth of data on the pattern and utility of clinical variables that can independently determine EEG abnormalities in GE. Objective: The study was designed to evaluate the frequency and pattern of EEG abnormality as well as assess the utility of clinical variables in predicting the likelihood of an abnormal EEG in GE. Methods: It was a cross-sectional study involving the analysis of EEGs of consecutive patients with clinical diagnosis of idiopathic GE from three centers over a 7-year period. Information on sociodemographic and seizure variables was obtained. The International Federation of Societies for Electroencephalography and Clinical Neurophysiology definition of interictal epileptiform discharges (interictal epileptiform activity [IEA]) was adopted in the study. Results: A total of 403 patients comprising 242 (60%) males and 161 (40%) females with clinical diagnosis of GE had EEG. Their age ranged between 2 weeks and 70 years, with a median age of 21 years and an interquartile age of 26 years. Two hundred and thirty-seven (58.8%) and 213 (52.9%) patients had abnormal EEG and IEA, respectively. Before adjustment for confounders, female gender (P = 0.0001), pediatric age group (P = 0.0388), duration of epilepsy of 1­4 years (P = 0.01387), uncontrolled seizure (P = 0.0060), and seizure frequency (P = 0.0001) were significantly associated with the presence of abnormal EEG. However, age, female gender, poor seizure control, and seizure frequencies were the independent predictors of EEG abnormality. Conclusion: The study showed that about 58% of patients with GE patients had abnormal EEG. Age, poor seizure control, and high frequency of seizure were independent predictors of the presence of EEG abnormality

The Assessment of Routine Electroencephalography in Patients with Altered Mental Status

PURPOSE: Changes in electroencephalography (EEG) patterns may offer a clue to the cause of altered mental status and suggest the prognoses of patients with such mental status. We aimed to identify the EEG patterns in patients with altered mental status and to correlate EEG findings with clinical prognoses. MATERIALS AND METHODS: We included 105 patients with altered mental status who underwent EEG. EEG and clinical chart reviews with ongoing patient follow-ups were performed to determine the clinical prognosis of the patients. Clinical data were sorted using the Glasgow Coma Scale (GCS) and Glasgow Outcome Scale (GOS). EEG findings were classified according to a method suggested by Scollo-Lavizzari. The EEGs were analyzed to find out whether any correlation existed with the prognoses of patients. RESULTS: Nonconvulsive status epilepticus (NCSE) was detected in only three patients (2.9%). Specific EEG patterns were observed in 28 patients. Twenty-nine (27.6%) patients expired, and 45 (42.9%) patients were in a vegetative state. EEG grade and GCS significantly correlated with GOS. EEG grade alone had a correlation with GCS. Patients with a severe EEG finding had a poor prognosis. CONCLUSION: EEG findings reflect the mental status of patients, and EEG grades are correlated with the clinical prognosis of patients. Although EEG is not frequently performed on patients with altered mental state, it can play a supplemental role in establishing a prognosis. Thus, the use of EEG should be emphasized in clinical setting.

ACTH therapy in refractory generalized epilepsy.

Adrenocorticotropic hormone (ACTH) has a long track record for the treatment of infantile spasms. However, there is paucity of data on the use of ACTH in the treatment of epilepsy beyond infantile spasms. We report the use of ACTH in two children with refractory generalized epilepsy. Both patients responded well. ACTH may be considered as a useful adjunctive therapy in patients with intractable generalized seizures. Side effects and cost however, remain important concerns.

Seizure in non-HIV cryptococcal meningitis.

OBJECTIVE: The authors studied the prevalence of seizure in non-HIV cryptococcal meningitis. MATERIAL AND METHOD: The records of non-HIV adult patients (age >15 years) diagnosed as cryptococcal meningitis in Srinagarind Hospital (Khon Kaen University) from 1990 to 1994 were reviewed All subjects were studied for the rate, pattern, and long-term result ofseizure. RESULTS: There were 105 cases. Eight patients (7.6%) had seizures at initial presentation. The pattern of seizure of six patients was generalized tonic-clonic seizure (GTC) and the others were focal seizure. Only one case still had seizures after treatment with conventional therapy of cryptococcal meningitis. At ten years follow up, ten cases had died, one patient still had seizures (the same case that had seizures after treatment) and one case with developed GTC after improvement of meningitis. CONCLUSION: GTC was the common pattern of seizure in non-HIV cryptococcal meningitis and mostly controlled by standard regimen of therapy for cryptococcal meningitis without any antiepileptic drugs.

The clinical spectrum of malformations of cortical development

BACKGROUND: Malformations of cortical development (MCD) usually manifest in childhood with epilepsy, developmental delay and focal neurological abnormalities. OBJECTIVE: To evaluate the presentation and severity of epilepsy in the different types of MCD. METHOD: We evaluated the first 100 consecutive patients with a neuroimaging diagnosis of MCD. They were identified among all the high resolution magnetic resonance imaging exams performed at our service between 1997 and 2001. The causes of referral were diverse, according to the routine of the neurology outpatient clinic. After magnetic resonance imaging diagnosis of the subtype of MCD a detailed clinical assessment was performed. RESULTS: There were 55 females and 45 males, with ages ranging from five months to 71 years old (mean=15.2 years). Seventy-seven patients presented with epilepsy. Sixty-one had partial epileptic syndromes, 13 secondary generalized syndromes, and in three, the type of epileptic syndrome could not be established. Epilepsy was less frequent in patients with the MCD subtypes of polymicrogyria and schizencephaly (p<0.001). Patients with schizencephaly and polymicrogyria had their seizures more easily controlled by antiepileptic drugs (p<0.001). CONCLUSION: That the frequency of epilepsy is lower and seizures are more easily controlled in the setting of polymicrogyria and schizencephaly. Patients with MCD frequently present with secondary generalized epilepsy early in childhood.

INTRODUÇÃO: As malformações do desenvolvimento cortical (MDC) geralmente se manifestam na infância, na forma de crises epilépticas, retardo do desenvolvimento neuropsicomotor ou anormalidades focais. OBJETIVO: Avaliar a apresentação clínica e a gravidade da epilepsia nos diferentes tipos de MDC. MÉTODO: Cem pacientes com diagnóstico de MDC estabelecido por neuroimagem foram avaliados. Os pacientes foram identificados através de exames de ressonância magnética de alta resolução realizados entre 1997 e 2001. As causas para investigação por imagem foram diversas, conforme as indicações de rotina dos ambulatórios de neurologia. Após a determinação do subtipo de MDC, uma avaliação clínica detalhada foi realizada. RESULTADOS: Entre os 100 pacientes, 55 eram do sexo feminino e 45 do masculino, com idade variando entre 5 meses e 71 anos (média=15,2 anos). Setenta e sete pacientes apresentaram epilepsia. Sessenta e um tinham síndrome epiléptica parcial, 13 síndrome epiléptica secundariamente generalizada e em três, o tipo de crise não pode ser definido. Epilepsia foi menos freqüente em pacientes com polimicrogiria e esquizencefalia (p<0.001). As crises epilépticas foram controladas mais facilmente por drogas antiepilépticas em pacientes com polimicrogiria e esquizencefalia (p<0.001). CONCLUSÃO: A freqüência de epilepsia é menor e as crises são mais facilmente controladas em pacientes com polimicrogiria e esquizencefalia. Pacientes com MDC freqüentemente apresentam síndrome epiléptica secundariamente generalizada.

Demencia frontotemporal no familiar y epilepsia generalizada / Frontotemporal dementia non familial and generalized epilepsy

Se presenta un paciente de 62 años, sin antecedentes familiares de demencia, que a los 45 años debuta con crisis súbitas de disnea, visión borrosa, caída al suelo y movimientos repetitivos de brazos. Tratado por epilepsia con fenitoína y ácido valproico, repite esporádicamente crisis semejantes. Hace 4 años sus familiares notan cambios de personalidad, irritabilidad y conductas obsesivas. Hace 2 años aparecen episodios de desorientación de días de duración, algunos con alucinaciones auditivas y también fenómenos convulsivos. Ultimamente presenta crisis polimorfas, algunas con prolongada alteración de conciencia, estados catatoniformes y relajación esfinteriana. Examen físico y neurológico sin anormalidades. Evaluación neuropsicológica evidenció consistentes defectos en funciones frontales. EEG mostraron lentitud generalizada y actividad irritativa esporádica en regiones frontotemporales. Atrofia cortical de predominio anterior en CT scan e hipoperfusión fronto-temporal bilateral en SPECT. Exámenes de laboratorio y LCR normales. CONCLUSION: La asociación de DFT con epilepsia, en forma no familiar, sugiere un síndrome neurodegenerativo cortical diferente.

Autism -- experiences in a tertiary care hospital.

Pervasive developmental disorders (PDD) or Autistic Spectrum Disorders (ASD) include Autistic Disorder (commonest), Asperger's syndrome, Childhood Disintegrative Disorders, Rett's syndrome and PDD-NOS (not otherwise specified). OBJECTIVE: Autism is an important cause of social disability and reported more often from the developed world than from the developing countries. The present study was aimed to establish the diagnosis of autism amongst children with derangements of language, communication and behavior; ascertain and treat the co-morbidities; identify underlying cause and create a sensitivity and awareness among various health care professionals. METHODS: Sixty-two of the seventy-five referred patients fulfilled the DSM-IV (Diagnostic and Statistical Manual of Mental Disorder) criteria for autism. Evaluation included a detailed history, clinical examination, IQ assessment, Connor's scoring for hyperactivity and Fragile-X screening. Management of co-morbidities was done. A follow up of these patients was done. Parents' assessment of the child was also done. A registry for autistic children was established at the Department of Pediatrics with other major institutions of Delhi. RESULTS : The male:female ratio was 8:1 and missed diagnosis was common. Professional awareness is merited. Behavioral modification by early intervention and stimulation improved the core symptoms of autism. Important co-morbidities included mental retardation (95%), hyperactivity (53%) and seizures (10%) cases. Control of co-morbidities in these children facilitated child's periodic assessment and implementation of intervention programmes. In the registry initiated 62 patients were enrolled at AIIMS and 6 were identified from other hospitals. CONCLUSION: Autism does occur in Indian children too. Diagnosis is often missed. Capacity building among health professionals by a more structured teaching of developmental disabilities in the medical curriculum is required. The need to attend to co-morbidities and associated symptoms was clear. The initiation of the registry and beginning of networking was important.

Continuous EEG monitoring in the evaluation of non-convulsive seizures and status epilepticus.

Non-convulsive seizures (NCSzs) and non-convulsive status epilepticus (NCSE) occur in a substantial proportion of patients with acute brain injury. These acute seizure disorders are often unrecognized and under-diagnosed. Seizure semiology of NCSz is too subtle clinically to be noticed. Most often, mental status impairment is the presenting feature. Changes in the functions of the thalamo-cortical system in patients with impaired consciousness can be detected by continuous EEG (cEEG) monitoring. cEEG monitoring allows detection of the changes at a reversible stage, often when there are no clinical indications of such phenomena. In addition EEG provides reasonable spatial resolution and excellent temporal resolution. This makes cEEG an excellent method for supplementing single or serial recordings in the detection of NCSzs and NCSE. Recent advances in digital EEG have made cEEG monitoring in the neurological intensive care unit (NICU) technically feasible. Current evidence suggests that the common clinical denominator associated with electrographic seizures or NCSzs is mental status impairment. In NCSE, the duration of ictal activity and the time of delay to diagnosis are independent predictors of poor outcome. It will be prudent to do cEEG monitoring in any patient with impaired consciousness either in the setting of acute brain injury or with no clear explanation to detect NCSzs/NCSE. Early recognition and timely intervention is likely to be associated with good outcomes.

Epilepsy in children with cerebral palsy.

This was a prospective analytical study done from October'99 through December 2000 to observe the clinical profile of epilepsy in children with cerebral palsy. Sixty epileptic children with cerebral palsy were studied and their results were compared with the results of epilepsy in 30 developmentally normal children. Ages of all children studied were 1-15 years. Majority were below five years of age and male out numbered female. Spastic quadriplegia (60%) was the commonest type of cerebral palsy. Generalized tonic-clonic seizure (66%) was the commonest seizure type in both groups. Second most common type of seizure was partial (13%) and myoclonic (29%) in developmentally normal and cerebral palsy children respectively. Mental retardation (63%) and speech delay (58%) were the two common associated problems in cerebral palsy patients. Ventriculomegaly (55%) was the commonest computed tomographic findings in cerebral palsy patients. In electro encephalography generalized epileptiform activity was the commonest finding in both groups. Clinical pattern is different in many ways when epilepsy is associated with cerebral palsy.

Profile of intractable epilepsy in a tertiary referral center.

This study was undertaken to find out the profile of intractable epilepsy (IE) in a tertiary referral centre. 100 patients (males 67; females 33) with IE attending the epilepsy clinic were evaluated. Detailed history, examination, investigations like EEG and CT scan and details regarding pharmacotherapy were analysed. The age of the patients ranged from 5 to 70 yrs (mean=23.2 yrs). Mean duration of seizures was 11.44 years. Commonest seizure type was partial seizures (74%). Amongst patients with generalised seizures (26%), 14% had multiple seizure types. The seizure frequency was 12.39 +/- 21.57 (mean +/- SD) per month. Fifty seven patients were in the symptomatic group with CNS infections being the leading cause (19%) of epilepsy. Fifty patients had one or more abnormal predictors of IE. There was no difference in the severity of epilepsy in patients with no abnormal feature when compared with patients having abnormal features. EEG was abnormal in 69% cases with background abnormality in 20% and focal abnormality in 36% cases. CT scan was abnormal in 41% cases with commonest abnormality being neurocysticercosis (11%) followed by gliosis (9%) and chronic infarct (9%). Sixty patients were receiving a combination of two drugs, 32 patients 3 drugs and 8 patients were on 4 drugs. There was no difference in seizure control in patients who were on 2 drugs or more than 2 drugs. Partial seizures were the commonest seizure type leading to IE; CNS infection being the leading aetiological factor. The presence or absence of predictors of intractability does not predict severity of epilepsy. Addition of third primary drug to existing combination only increases adverse effects without better control of seizures.

Neurological complications of eclampsia.

OBJECTIVE: A prospective study was conducted to evaluate the various neurological (clinical, radiological and EEG) complications in patients of eclampsia. METHODS: Thirty nine patients of eclampsia were studied regarding neurological findings at presentation and electroencephalographic (EEG) tracings were recorded in each patient. Patients with an abnormal neurologic examination and/or focal or lateralizing findings on EEG, underwent a CT scan (n = 18). Foetal and maternal outcome were recorded. RESULTS: The age of the patients ranged from 19-30 (mean +/- SD, 24.2 +/- 3.5) years thirty six patients (92%) had seizures in the antenatal period, 2 (5.4%) patients developed post partum eclampsia and 1 (2.6%) patient had seizures before and after delivery. A diffuse encephalopathy was seen in 9 patients (23.1%), 4 patients (10.2%) had hemiparesis and 1 patient (2.6%) had papilledema. EEG abnormalities were seen in 29 cases (74%) and included generalized slowing (n = 19), generalized sharp waves (n = 9), focal slowing (n = 4), focal sharp waves (n = 2) and spikes (generalized and focal) were seen in 1 patient each. Abnormal CT scan was seen in 10 cases (n = 18). Five patients had generalized infarct was seen in 1 patient each. There were 8 (20.5%) still births and 31 (19.5%) live births and no maternal mortality. CONCLUSIONS: Antenatal seizures occur in > 90% cases of eclampsia and less than 10% cases have seizures after delivery. A diffuse encephalopathy is the commonest clinical abnormality along with generalized slowing on EEG. Although cerebral oedema is common focal infarcts may be seen on CT scan.

Epilepsia fotosensible: aspectos clínicos y electroencefalográficos / Photosensitive epilepsy: clinics and electroencephalografic aspect

El objetivo de este estudio es la evaluación clínica y electroencefalográfica de las epilepsias fotosensibles. Se analizaron 14 pacientes (p) con epilepsia fotosensible EF, 9 de ellos con EF pura y 5 p con crisis autoinducidas. 10 fueron varones y 4 mujeres. Edad media de comienzo de las crisis autoinducidas 5 ñ 2 años (2-8) y de la epilepsia fotosensible pura, 9 ñ 3 años (4-13). El tiempo de seguimiento fué de 11 ñ 10 años (1-30). A todos se les realizó un electroencefalograma (EEG) con estimulación luminosa intermitente (ELI) en 1994. Las crisis fueron inducidas por el sol en 3 p, televisión (TV) en 4 p, sol y TV en 4 p, y video-juegos en 3 pacientes; 12 epilepsias fueron idiopáticas y 2 sintomáticas. Antecedentes familiares de epilepsia se determinaron en un 43 por ciento. Luego del tratamiento, 5 p normalizaron su EEG (35,71 por ciento) pero 9 p (64,29 por ciento) conservan la respuesta anormal a la ELI y de éstos últimos 7 continúan con crisis. Todos los p con crisis por video-juegos una vez comenzado el tratamiento normalizaron el EEG y no presentaron más crisis. Conclusión: Entre las epilepsias fotosensibles puras aquellas inducidas por video-juegos parecen ser las más benignas. La persistencia del EEG con respuesta fotoconvulsiva predice el pobre control de las crisis fotosensibles

Diagnóstico electroencefalográfico / Electroencephalographic diagnosis

El electroencefalograma (EEG) es el registro de la actividad elétrica cerebral obtenido por electrodos colocados sobre el cráneo. Se describe la técnica, la actividad electroencefalográfica normal, la actividad anormal, principalmente en el paciente epiléptico haciendo especial hincapié en las crisis generalizadas, focales y del recién nacido. Se menciona los cambios que puede sufrir el EEG en las diferentes fases de la enfermedad y el valor pronóstico del mismo