Li Li Min

Memory and language impairments and their relationships to hippocampal and perirhinal cortex damage in patients with medial temporal lobe epilepsy

Chronic medial temporal lobe epilepsy (MTLE) is associated with memory loss due to damage in the hippocampal system. To investigate the relationship between volume of medial temporal lobe structures and performance on neuropsychological tests, we studied 39 consecutive patients with MTLE and unilateral hippocampal atrophy (HA) determined by volumetric magnetic resonance imaging (MRI). Structures of interest comprised hippocampus, amygdala, and entorhinal, perirhinal, parahippocampal, and temporopolar cortices. The findings indicated that (1) performance was significantly worse in the group with left HA as compared with the group with right HA on general memory, verbal memory, delayed recall, and verbal fluency tests and the Boston Naming Test (BNT), and (2) the volume of the left hippocampus and also the degree of asymmetry of perirhinal cortex volume were significant and independent predictors of performance on general memory, verbal memory, and verbal fluency tests and the BNT in patients with MTLE.

Extrahippocampal gray matter atrophy and memory impairment in patients with medial temporal lobe epilepsy

Memory impairment observed in patients with medial temporal lobe epilepsy (MTLE) is classically attributed to hippocampal atrophy. The contribution of extrahippocampal structures in shaping memory impairment in patients with MTLE is not yet completely understood, even though atrophy in MTLE extends beyond the hippocampus. We aimed to evaluate the neuropsychological profile of patients with MTLE focusing on memory, and to investigate whether gray matter concentration (GMC) distribution within and outside the medial portion of the temporal lobes would be associated with their neuropsychological performance. We performed a voxel based morphometry study of 36 consecutive patients with MTLE and unilateral hippocampal atrophy. We observed a significant simple regression between general and verbal memory performance based on Wechsler Memory Scale—Revised and the GMC of medial temporal and extratemporal structures in patients with left MTLE. We also performed a “regions of interest analysis” of the medial temporal lobe, and we observed that the GMC of the hippocampus, entorhinal, and perirhinal cortices were consistently associated with general and verbal memory performance in patients with MTLE. We also observed that the GMC of the cingulate and orbito‐frontal cortex are independently associated with verbal and general memory performances. Our results suggest that general and verbal memory impairments in patients with left MTLE are associated with atrophy of the hippocampus, the entorhinal, and the perirhinal cortex. We also suggest that atrophy and dysfunction of limbic and frontal structures such as the cingulate and the orbito‐frontal cortex contribute to memory impairment in MTLE. Hum Brain Mapp 2007.

Urban prevalence of epilepsy: populational study in São José do Rio Preto, a medium-sized city in Brazil

ANTECEDENTES: O objetivo deste estudo foi determinar a prevalencia da epilepsia na populacao urbana de Sao Jose do Rio Preto, com 336000 habitantes, localizada no noroeste do Estado de Sao Paulo/ Brasil. METODO: O estudo populacional, tipo corte transversal, em amostra aleatoria, constituiuse de uma fase de rastreamento, mediante um questionario. O padrao ouro para confirmacao diagnostica foi a historia clinica e o exame neurologico. Os testes do c2 e intervalo de confianca de 95% (IC95%) foram usados para analise dos resultados, tendo sido considerados significantes os de valor p< 0,05. RESULTADOS: A amostra estudada foi de 17293 pessoas, cuja distribuicao quanto ao sexo, a faixa etaria e a raca foram semelhantes a da populacao em geral. A prevalencia de epilepsia por 1000 hab. foi 18,6, sendo 8,2 para ativa considerandose, pelo menos, uma crise no periodo dos ultimos 2 anos. A prevalencia na faixa etaria de 0 a 4 anos foi 4,9, de 5 a 14, 11,7; de 15 a 64, 20,3; e acima dos 65 anos foi 32,8. CONCLUSAO: As prevalencias de epilepsia acumulada e ativa foram elevadas, semelhantes as dos paises em desenvolvimento, em particular, aos da America Latina. A prevalencia de epilepsia na infância foi baixa, enquanto que nos idosos foi elevada, semelhantes as observadas em paises desenvolvidos. Estes resultados sao relevantes no planejamento de medidas sanitarias, adequacao ao tratamento da populacao, considerando a alta prevalencia encontrada, para minimizar o impacto da epilepsia na populacao.UNLABELLED The aim of this study was to determine the prevalence of epilepsy in the urban population of São José do Rio Preto. This is a medium-sized city of 336000 inhabitants, located in the northwest of the state of São Paulo, Brazil. METHOD A cross-sectional epidemiological investigation with a randomized sample was performed in two phases, a screening phase and a confirmation of the diagnosis phase. The gold standard was a clinical investigation and neurological examination. The chi-square test was used in analysis of the results and p-value value < 0.05 was considered significant. Prevalence was calculated with 95% confidence interval. RESULTS The study sample size was 17293 individuals, with distributions of gender, age, and race similar to the general population. The prevalence per 1000 inhabitants of epilepsy was 18.6, of these 8.2 were active, defined as at least one seizure within the last two years. The prevalence per 1000 inhabitants for the age groups (years) was 4.9 (04), 11.7 (514), 20.3 (1564) and 32.8 (65 or over). CONCLUSION Prevalence of both accumulated and active epilepsy was elevated, comparable to other developing nations, in particular those of Latin America. However, the prevalence of epilepsy in childhood was low, whilst in aged individuals it was high similar to industrialized nations.

Menstrual cycle worsening of epileptic seizures in women with symptomatic focal epilepsy

INTRODUCTION Hormonal fluctuation is responsible for worsening of epileptic seizures during the menstrual cycle. OBJECTIVE To identify irregularities in the menstrual cycles of women with mesial temporal lobe epilepsy (MTLE) and extratemporal focal epilepsy (ETFE) and correlate the frequency of seizures during the menstrual cycles. METHOD We evaluated prospectively women in the menacme with MTLE and ETFE. Calendars were provided for these patients, and they were asked to mark their seizure frequency according to the menses. Calendars were reviewed in each routine medical appointment. RESULTS Thirty-nine patients with MTLE and 14 with ETFE were evaluated. We registered 211 cycles in the patients with MTLE and 49 in those with ETFE. Irregular menstrual cycles were found in 28 (28/39, 71.7%) patients with MTLE and 6 (6/14, 42.8%) with ETFE (p=0.052). Premenstrual seizure worsening was observed in 46 (21.8%) patients with MTLE and 9 (18.3%) with ETFE (p=0.596). Menstrual worsening was observed in 47 (22.2%) patients with MTLE and 15 (30.6%) with ETFE (p=0.217). Ovulatory worsening was observed in 36 (17%) patients with MTLE and 13 (26.5%) with ETFE (p=0,126). Catamenial worsening was observed in 58 (27.4%) of the patients with MTLE and in 17 (34.7%) of the patients with ETFE (p=0.315). CONCLUSION There was no difference between the group of patients with MTLE and ETFE regarding the frequency of irregular cycles and seizure worsening during the premenstrual, menstrual, catamenial or ovulatory periods.

Magnetic Resonance Spectroscopy in Epilepsy: Clinical Issues

Summary: Proton magnetic resonance spectroscopy (MRS) studies have shown focal reductions of N‐acetyl aspartate (NAA) signal in patients with different forms of temporal lobe epilepsy (TLE), including those with normal magnetic resonance imaging (MRI), as well as extratemporal partial epilepsies. Both single‐voxel and multivoxel 1H‐MRS have high sensitivity for detecting low NAA, indicative of neuronal dysfunction in focal epilepsies. Decreases in NAA correlate strongly with EEG abnormalities and severity of cell loss, and may be a more sensitive measure than structural MRI. However, the NAA decrease is often more widespread than the epileptogenic focus. The results of published MRS studies suggest that in patients with partial epilepsy, there is a metabolic abnormality throughout the brain, with patterns of asymmetry and focal accentuation that are useful for noninvasive localization of epileptogenic foci. A major limitation of current proton MRS studies in epilepsy is the inability to cover the entire brain in a single acquisition, thus leading to major sampling bias. The area of maximal abnormality may reside farther away, even when there is an abnormality inside of the volume of interest used for that particular examination. Decreased NAA ratios are present even in children at the onset of their epilepsy, and evidence points to a gradual and progressive course of further reduction in NAA values. Conversely, the relative NAA concentration can recover ipsilaterally and contralaterally after successful resection of a temporal lobe focus. These observations, together with the fact of the often widespread NAA abnormality, must be taken into account for the correct and adequate interpretation of proton MRS studies in the assessment of partial epilepsies.

Suicidal thoughts in epilepsy: A community-based study in Brazil

Epilepsy has been associated with increased risk of suicide; however, few studies have examined the relationship between epilepsy and suicidal behavior. The aims of this study were to evaluate the frequency of suicidal behavior in people with epilepsy and to identify characteristics that are associated with suicidal ideation in epilepsy. Of 171 people with epilepsy identified in a previous survey, 139 were included. A structured interview was conducted, and a second psychiatric evaluation was scheduled for those who agreed. The frequencies of suicidal thoughts, plans, and attempts during lifetime were 36.7, 18.2, and 12.1%, respectively. The following conditions were strongly associated with suicidal thoughts: anxiety (OR=3.3, 95% CI=1.4-7.5, P=0.001), depression (OR=4.8, 95% CI=1.9-12.5, P=0.001), and two or more standardized psychiatric diagnoses (OR=21.6, 95% CI=4.4-105.9, P<0.0001). Although specific characteristics of epilepsy were found to be related to suicidal thoughts, psychiatric diseases also play an essential role.

Memory impairment in children with temporal lobe epilepsy: a review

INTRODUCAO: Os autores apresentam um artigo de revisao sobre memoria em epilepsia de lobo temporal na infância. METODO: Realizou-se levantamento bibliografico sobre o assunto, acrescido de contribuicoes pessoais. RESULTADOS: Epilepsia de lobo temporal (ELT) na infância apresenta grande diversidade clinica, etiologica e eletrencefalografica. As caracteristicas neuropsicologicas de criancas com ELT ainda nao estao claramente definidas. A relacao entre lateralizacao da lesao e desempenho na realizacao dos testes tambem nao esta totalmente elucidada. CONCLUSAO: Na infância, os resultados dos estudos em ELT em relacao aos deficits de memoria sao controversos. Isso pode estar relacionado a diversidade clinica, etiologica e eletrencefalografica existente. Alem disso, a forma de avaliacao entre os estudos e muito variavel havendo diferencas quanto a natureza dos testes utilizados. Assim, fica claro que mais estudos sao necessarios para elucidar o perfil neuropsicologico das criancas com ELT.

A Brazilian original pedagogical approach to the teaching of neurology

UNLABELLED The two-arm Clinical Decisions/Diagnostic Workshop (CD/DW) approach to undergraduate medical education has been successfully used in Brazil. OBJECTIVE Present the CD/DW approach to the teaching of stroke, with the results of its pre-experimental application and of a comparative study with the traditional lecture-case discussion approach. METHOD Application of two questionnaires (opinion and Knowledge-Attitudes-Perceptions-KAP) to investigate the non-inferiority of the CD/DW approach. RESULTS The method was well accepted by teachers and students alike, the main drawback being the necessarily long time for its completion by the students, a feature that may better cater for different educational needs. The comparative test showed the CD/DW approach to lead to slightly higher cognitive acquisition as opposed to the traditional method, clearly showing its non-inferiority status. CONCLUSION The CD/DW approach seems to be another option for teaching neurology in undergraduate medical education, with the bonus of respecting each learner`s time.

Segmentation and construction of thalamus template from magnetic resonance images

Segmentation and construction of thalamus template from magnetic resonance images Alline F. B. Camargo (IC), Daniel S. F. Magalhães (PQ), Li Li Min (PQ). Abstract The creation of thalamus templates assists in the study of structure, collaborating with surgical planning, giving greater structural visibility and allowing better viewing of its relation to other brain structure. Moreover the templates can be used in selective quantification in other modalities of structural and functional neuroimaging.