Width of sulcus and thickness of gyrus in patients with cerebral atherosclerosis: a new tool for the prevention of vascular cognitive impairment

SUMMARY BACKGROUND AND PURPOSE Cerebral atherosclerosis is the main cause of lesions that contribute to vascular cognitive impairment and vascular dementia, followed by arteriosclerosis of small vessels and cerebral amyloid angiopathy. The purpose of this study was to compare the post-mortem radiological alterations of autopsied adults with the macroscopic alterations in the posterior region of these brains in order to establish a relationship between the two forms of analysis and to discuss the relevance of the prevention of vascular cognitive impairment in patients with encephalic atherosclerosis. MATERIALS AND METHODS Thirteen brains were analysed macroscopically to assess the degree of atherosclerosis of the basilar and the posterior cerebral arteries. The patients were autopsied in the Subject of General Pathology at General Hospital of Triângulo Mineiro Federal University in Uberaba, state of Minas Gerais, Brazil. The qualitative analysis of atherosclerosis was performed with classification into mild, moderate or severe. In the posterior region of the brains, width of sulcus and thickness of gyrus were measured by macroscopic analysis and by tomographic analysis. RESULTS AND CONCLUSIONS There was a decrease in calcarine sulcus width and an increase in medial temporal occipital gyrus thickness in patients with a higher degree of atherosclerosis, macroscopically and in tomography, respectively. Low oxygenation caused by atherosclerosis probably leads to an encephalic parenchyma inflammation that causes microglial cells hypertrophy provoking increase in the gyrus thickness and decrease in the sulcus width, as observed in the present study.

RESUMO INTRODUÇÃO E OBJETIVO A aterosclerose cerebral é a principal causa de lesões que contribuem para o comprometimento cognitivo vascular (CCV) e demência vascular, seguida da arteriosclerose de pequenos vasos e da angiopatia amiloide cerebral. Sendo assim, este estudo comparou as alterações radiológicas post mortem de adultos autopsiados com as alterações macroscópicas na região posterior desses encéfalos a fim de estabelecer uma relação entre as duas formas de análise e discutir sobre a relevância da prevenção do CCV em pacientes com aterosclerose encefálica. MATERIAL E MÉTODOS Treze encéfalos foram analisados macroscopicamente para avaliar o grau de aterosclerose das artérias basilar e cerebral posterior. Os pacientes foram autopsiados na disciplina de Patologia Geral no HC-UFTM em Uberaba, Minas Gerais, Brasil. A análise qualitativa da aterosclerose foi realizada com as classificações discreta, moderada ou acentuada. A espessura dos giros e a largura dos sulcos na região posterior dos encéfalos foram analisadas macroscopicamente e por tomografia computadorizada. RESULTADOS E CONCLUSÃO Houve diminuição na largura do sulco calcarino e aumento na espessura do giro occipital temporal medial de acordo com o aumento do grau de aterosclerose macroscopicamente e por tomografia, respectivamente. A baixa oxigenação causada pela aterosclerose provoca a inflamação do parênquima encefálico, provavelmente levando à hipertrofia das células da micróglia e ao consequente aumento dos giros e estreitamento dos sulcos, como observado no presente estudo.

Extratemporal abnormalities in phosphorus magnetic resonance spectroscopy of patients with mesial temporal sclerosis / Anormalidades extratemporais na espectroscopia de fósforo por ressonância magnética em pacientes com esclerose mesial temporal

ABSTRACT Objective We evaluated extratemporal metabolic changes with phosphorus magnetic resonance spectroscopy (31P-MRS) in patients with unilateral mesial temporal sclerosis (MTS). Method 31P-MRS of 33 patients with unilateral MTS was compared with 31 controls. The voxels were selected in the anterior, posterior insula-basal ganglia (AIBG, PIBG) and frontal lobes (FL). Relative values of phosphodiesters- PDE, phosphomonoesters-PME, inorganic phosphate - Pi, phosphocreatine- PCr, total adenosine triphosphate [ATPt = γ- + a- + b-ATP] and the ratios PCr/ATPt, PCr/γ-ATP, PCr/Pi and PME/PDE were obtained. Results We found energetic abnormalities in the MTS patients compared to the controls with Pi reduction bilaterally in the AIBG and ipsilaterally in the PIBG and the contralateral FL; there was also decreased PCr/γ-ATP in the ipsilateral AIBG and PIBG. Increased ATPT in the contralateral AIBG and increased γ-ATP in the ipsilateral PIBG were detected. Conclusion Widespread energy dysfunction was detected in patients with unilateral MTS.

RESUMO Objetivo Nós avaliamos as alterações metabóblicas através da espectroscopia de fósforo por ressonância magnética (31P-MRS) em pacientes com esclerose mesial temporal (EMT) unilateral. Método 31P-MRS de 33 pacientes com EMT unilateral foram comparadas aos de 31 controles. Foram selecionados os voxels nas regiões insulonuclear anterior e posterior (RINA e RINP) e frontal (RF). Os valores relativos de fosfodiésteres – PDE, fosfomonoésteres- PME, fosfato inorgânico- Pi, fosfocreatina –PCr, adenosina trifosfato total [ATPt = γ- + a- + b-ATP] e as razões PCr/ATPt, PCr/γ-ATP, PCr/Pi e PME/PDE foram obtidas. Resultados Nós encontramos anormalidades em pacientes com EMT em comparação aos controles. Redução de Pi nas RINA bilateralmente, RINP ipsilateral e RF contralateral, redução de PCr/γ-ATP nas RINA e RINP ipsilaterais foram detectadas. Aumentos de ATPT na RINA contralateral e aumento de γ-ATP na RINP ipsilateral também foram encontradas. Conclusão Disfunção energética difusa foi encontrada em pacientes com EMT unilateral.

Gross-total resection of temporal low grade gliomas is a critically important factor in achieving seizure-freedom / A ressecção total de gliomas temporais de baixo grau é um importante fator no controle das crises convulsivas

Objective To present a surgical series of patients with low grade temporal gliomas causing intractable epilepsy, focusing on long-term seizure outcome.Method A retrospective study was conducted with patients with temporal low-grade gliomas (LGG).Results Sixty five patients with were operated in our institution. Males were more affected than females and the mean age at surgery was 32.3 ± 8.4 (9-68 years). The mean age at seizure onset was 25.7 ± 9.2 (11-66 years). Seizure outcome was classified according with Engel classification. After one year of follow up, forty two patients (64.6%) were Engel I; seventeen (26.2%) Engel II; four (6.2%) Engel III and two (3.1%) Engel IV. Statistically significant difference in seizure outcome was obtained when comparing the extension of resection. Engel I was observed in 39 patients (69.6%) with total resection and in only 3 (33.3%) patients with partial resection.Conclusion Gross-total resection of temporal LGGs is a critically important factor in achieving seizure-freedom.

Objetivo Apresentar uma série cirúrgica de pacientes com gliomas temporais de baixo grau, causando epilepsia de difícil controle.Método Estudo retrospectivo de pacientes com diagnóstico de glioma temporal de baixo grau temporais.Resultados 65 pacientes com foram operados em nossa instituição. A média de idade de início das crises foi de 25,7 ± 9,2 (11-66 anos). Após um ano de acompanhamento, quarenta e dois pacientes (64,6%) estavam Engel I; dezessete (26,2%) Engel II; quatro (6,2%) Engel III e dois (3,1%) Engel IV. Houve diferença estatisticamente significativa no resultado do controle das crises quando se compara a extensão da ressecção. Engel I foi observada em 39 pacientes (69,6%) com a ressecção total e em apenas 3 (33,3%) pacientes com ressecção parcial.Conclusão A ressecção total de glioma temporal de baixo grau temporais é um fator extremamente importante no controle das crises.

Small calcified lesions suggestive of neurocysticercosis are associated with mesial temporal sclerosis / Pequenas lesões calcificadas sugestivas de neurocisticercose e estão associadas com esclerose mesial temporal

Recent studies have suggested a possible relationship between temporal lobe epilepsy with mesial temporal sclerosis (MTS) and neurocysticercosis (NC). We performed a case-control study to evaluate the association of NC and MTS. Method: We randomly selected patients with different epilepsy types, including: MTS, primary generalized epilepsy (PGE) and focal symptomatic epilepsy (FSE). Patients underwent a structured interview, followed by head computed tomography (CT). A neuroradiologist evaluated the scan for presence of calcified lesions suggestive of NC. CT results were matched with patients’ data. Results: More patients in the MTS group displayed calcified lesions suggestive of NC than patients in the other groups (p=0.002). On multivariate analysis, MTS was found to be an independent predictor of one or more calcified NC lesions (p=0.033). Conclusion: After controlling for confounding factors, we found an independent association between NC calcified lesions and MTS. .

Estudos recentes têm sugerido possível relação entre epilepsia do lobo temporal com esclerose mesial temporal (MTS) e neurocisticercose (NC). Conduzimos um estudo caso-controle para avaliar a associação de NC e MTS. Método: Selecionamos randomicamente pacientes com diferentes tipos de epilepsia, incluindo: MTS, epilepsia primariamente generalizada (PGE) e epilepsia focal sintomática (FSE). Pacientes foram submetidos a uma entrevista estruturada, seguida por uma tomografia computadorizada de crânio (CT). Um neuroradiologista avaliou as imagens quanto à presença de lesões calcificadas sugestivas de NC. Resultados das CT foram comparados com os dados dos pacientes. Resultados: Mais pacientes do grupo MTS apresentaram lesões calcificadas sugestivas de NC que de outros grupos (p=0,002). Na análise multivariável, MTS foi um preditor independente de uma ou mais calcificações sugestivas de NC (p=0,033). Conclusão: Após controlar para fatores confusionais, encontramos uma associação independente entre lesões calcificadas de NC e MTS. .

Altered Activity and Functional Connectivity of Superior Temporal Gyri in Anxiety Disorders: A Functional Magnetic Resonance Imaging Study

OBJECTIVE: The prior functional MRI studies have demonstrated significantly abnormal activity in the bilateral superior temporal gyrus (STG) of anxiety patients. The purpose of the current investigation was to determine whether the abnormal activity in these regions was related to a loss of functional connectivity between these regions. MATERIALS AND METHODS: Ten healthy controls and 10 anxiety patients underwent noninvasive fMRI while actively listening to emotionally neutral words alternated by silence (Task 1) or threat-related words (Task 2). The participants were instructed to silently make a judgment of each word's valence (i.e., unpleasant, pleasant, or neutral). A coherence analysis was applied to the functional MRI data to examine the functional connectivity between the left and the right STG, which was selected as the primary region of interest on the basis of our prior results. RESULTS: The data demonstrated that the anxiety patients exhibited significantly increased activation in the bilateral STG than the normal controls. The functional connectivity analysis indicated that the patient group showed significantly decreased degree of connectivity between the bilateral STG during processing Task 2 compared to Task 1 (t = 2.588, p = 0.029). In addition, a significantly decreased connectivity was also observed in the patient group compared to the control group during processing Task 2 (t = 2.810, p = 0.012). CONCLUSION: Anxiety patients may exhibit increased activity of the STG but decreased functional connectivity between the left and right STG, which may reflect the underlying neural abnormality of anxiety disorder, and this will provide new insights into this disease.

Surgical and postmortem pathology studies: contribution for the investigation of temporal lobe epilepsy / Patologia cirúrgica e post mortem: contribuição para a investigação da epilepsia do lobo temporal

Pathology studies in epilepsy patients bring useful information for comprehending the physiopathology of various forms of epilepsy, as well as aspects related to response to treatment and long-term prognosis. These studies are usually restricted to surgical specimens obtained from patients with refractory focal epilepsies. Therefore, most of them pertain to temporal lobe epilepsy (TLE) with mesial temporal sclerosis (MTS) and malformations of cortical development (MCD), thus providing information of a selected group of patients and restricted regions of the brain. Postmortem whole brain studies are rarely performed in epilepsy patients, however they may provide extensive information on brain pathology, allowing the analysis of areas beyond the putative epileptogenic zone. In this article, we reviewed pathology studies performed in epilepsy patients with emphasis on neuropathological findings in TLE with MTS and MCD. Furthermore, we reviewed data from postmortem studies and discussed the importance of performing these studies in epilepsy populations.

Estudos de patologia em pacientes com epilepsia trazem informações úteis para compreender a fisiopatologia de várias formas de epilepsia, bem como aspectos relacionados ao tratamento e ao prognóstico a longo prazo. Esses estudos são usualmente restritos a espécimes cirúrgicos obtidos de pacientes com epilepsias focais refratárias. Portanto, a maioria diz respeito à epilepsia do lobo temporal (ELT) com esclerose mesial temporal (EMT) e às malformações do desenvolvimento cortical (MDC). Desse modo, fornecem informações sobre um grupo selecionado de pacientes e sobre regiões restritas do cérebro. Raramente são realizados estudos post mortem do cérebro inteiro em pacientes com epilepsia; entretanto, eles podem prover informações relevantes sobre patologia cerebral, permitindo a análise de áreas além da zona epileptogênica putativa. Neste artigo, foram revisados estudos de patologia feitos em pacientes com epilepsia, com ênfase nos achados neuropatológicos em ELT com EMT e MDC. Foram revisados, ainda, dados de estudos post mortem e discutiu-se a importância da realização desses estudos em populações de pessoas com epilepsia.

Temporal lobe epilepsy with mesial temporal sclerosis: hippocampal neuronal loss as a predictor of surgical outcome / Epilepsia do lobo temporal com esclerose mesial temporal: o padrão da perda neuronal hipocampal como preditor do prognóstico cirúrgico

OBJECTIVE: To analyze retrospectively a series of patients with temporal lobe epilepsy (TLE) and mesial temporal sclerosis (MTS), and the association of patterns of hippocampal sclerosis with clinical data and surgical prognosis. METHOD: Sixty-six patients with medically refractory TLE with unilateral MTS after anterior temporal lobectomy were included. Quantitative neuropathological evaluation was performed on NeuN-stained hippocampal sections. Patient's clinical data and surgical outcome were reviewed. RESULTS: Occurrence of initial precipitating insult (IPI), as well as better postoperative seizure control (i.e. Engel class 1), were associated with classical and severe patterns of hippocampal sclerosis (MTS type 1a and 1b, respectively). CONCLUSION: Quantitative evaluation of hippocampal neuronal loss patterns predicts surgical outcome in patients with TLE-MTS.

OBJETIVO: Analisar retrospectivamente uma série de pacientes com epilepsia do lobo temporal (ELT) e esclerose mesial temporal (EMT), bem como correlacionar os padrões de esclerose hipocampal com os dados clínicos e o prognóstico cirúrgico. MÉTODOS: Foram incluídos neste estudo 66 pacientes com ELT refratária a tratamento medicamentoso e com EMT unilateral submetidos à lobectomia temporal anterior. A análise neuropatológica quantitativa foi realizada em seções hipocampais imunomarcadas com NeuN. Dados clínicos e resultados do acompanhamento pós-cirúrgico foram revisados. RESULTADOS: Ocorrência de evento precipitante inicial e melhor controle de crises após a cirurgia (i.e. classe 1 de Engel) foram associados aos padrões clássico (EMT tipo 1a) e severo (EMT tipo 1b) de esclerose hipocampal. CONCLUSÃO: A análise quantitativa do padrão de perda neuronal do hipocampo é capaz de predizer o prognóstico cirúrgico em pacientes com ELT-EMT.

Relationship between fluid-attenuated inversion-recovery (FLAIR) signal intensity and inflammatory mediator's levels in the hippocampus of patients with temporal lobe epilepsy and mesial temporal sclerosis / Correlação da intensidade do sinal em FLAIR e os níveis de mediadores inflamatórios no hipocampo de pacientes com epilepsia do lobo temporal e esclerose mesial temporal

We investigated a relationship between the FLAIR signal found in mesial temporal sclerosis (MTS) and inflammation. Twenty nine patients were selected through clinical and MRI analysis and submitted to cortico-amygdalo-hippocampectomy to seizure control. Glutamate, TNFα, IL1, nitric oxide (NO) levels and immunostaining against IL1β and CD45 was performed. Control tissues (n=10) were obtained after autopsy of patients without neurological disorders. The glutamate was decreased in the temporal lobe epilepsy (TLE) -MTS group (p<0.001), suggesting increased release of this neurotransmitter. The IL1β and TNFα were increased in the hippocampus (p<0.05) demonstrating an active inflammatory process. A positive linear correlation between FLAIR signal and NO and IL1β levels and a negative linear correlation between FLAIR signal and glutamate concentration was found. Lymphocytes infiltrates were present in hippocampi of TLE patients. These data showed an association between hippocampal signal alteration and increased inflammatory markers in TLE-MTS.

Este estudo foi delineado para investigar a presença de relação entre a intensidade de sinal em FLAIR e níveis de citocinas, óxido nítrico (NO) e glutamato no hipocampo de pacientes com epilepsia do lobo temporal refratária, associada com esclerose mesial (TLE-MTS). Vinte e nove pacientes foram selecionados através de análise clínica e de ressonância magnética (RM) que foram submetidos a cortico-amigdalo-hipocampectomia para o controle das crises. Os níveis de glutamato foram avaliados por HPLC, as citocinas TNFα e IL1β por ELISA e os níveis de NO via NO system. Avaliamos também por imuno-histoquímica a expressão de IL1β e CD45 em tecidos controles e com esclerose. Tecido controle foi obtido após autópsia de indivíduos mortos sem disfunções inflamatórias e neurológicas (n=10). A concentração de glutamato se mostrou reduzida no tecido TLE-MTS (p<0,001) sugerindo aumento na liberação desse neurotransmissor. TNFα e IL1β também apresentaram níveis elevados no hipocampo dos pacientes (p<0,05), demonstrando um processo inflamatório crônico. Houve uma correlação linear positiva entre a intensidade do sinal em FLAIR e os níveis de NO e IL1β. Em contraste, uma correlação linear negativa foi encontrada entre a intensidade do sinal em FLAIR e níveis de glutamato no hipocampo com esclerose. Infiltrado linfocitário hipocampal também foi visualizado pela imuno-marcação com CD45 em pacientes com TLE-MTS. Esses dados mostraram uma associação entre alteração de sinal na RM e marcadores inflamatórios em pacientes com TLE-MTS.

Relapse of herpes simplex encephalitis presenting as choreoathetosis.

We report a case of herpes simplex virus (HSV) encephalitis (HSE) in an 11-year-old boy who recovered with acyclovir therapy but developed relapse after 2 weeks. Choreoathetosis was the presenting feature of relapse. Response to antiinflammatory treatment was excellent. To the best of our knowledge, this is the first case of HSE relapse presenting with choreoathetosis reported from India. We describe the patient and review the literature on HSE and HSE relapse.

Electrophysiological and auditory behavioral evaluation of individuals with left temporal lobe epilepsy / Avaliação eletrofisiológica e comportamental da audição em individuos com epilepsia em lobo temporal esquerdo

The purpose of this study was to determine the repercussions of left temporal lobe epilepsy (TLE) for subjects with left mesial temporal sclerosis (LMTS) in relation to the behavioral test-Dichotic Digits Test (DDT), event-related potential (P300), and to compare the two temporal lobes in terms of P300 latency and amplitude. We studied 12 subjects with LMTS and 12 control subjects without LMTS. Relationships between P300 latency and P300 amplitude at sites C3A1,C3A2,C4A1, and C4A2, together with DDT results, were studied in inter-and intra-group analyses. On the DDT, subjects with LMTS performed poorly in comparison to controls. This difference was statistically significant for both ears. The P300 was absent in 6 individuals with LMTS. Regarding P300 latency and amplitude, as a group, LMTS subjects presented trend toward greater P300 latency and lower P300 amplitude at all positions in relation to controls, difference being statistically significant for C3A1 and C4A2. However, it was not possible to determine laterality effect of P300 between affected and unaffected hemispheres.

O objetivo deste estudo foi determinar a repercussão da epilepsia de lobo temporal esquerdo (LTE) em indivíduos com esclerose mesial temporal esquerda (EMTE) em relação à avaliação auditiva comportamental-Teste Dicótico de Dígitos (TDD), ao Potencial Evocado Auditivo de Longa Latência (P300) e comparar o P300 do lobo temporal esquerdo e direito. Estudamos 12 indivíduos com EMTE (grupo estudo) e 12 indivíduos controle com desenvolvimento típico. Analisamos as relações entre a latência e amplitude do P300, obtidos nas posições C3A1,C3A2,C4A1 e C4A2 e os resultados obtidos no TDD. No TDD, o grupo estudo apresentou pior desempenho em relação ao grupo controle, sendo esta diferença estatisticamente significante em ambas as orelhas. Para o P300, observamos que em seis indivíduos com EMTE o potencial foi ausente. Para a latência e amplitude, verificamos que estes indivíduos apresentaram uma tendência ao aumento da latência e redução da amplitude para todas as posições em relação ao grupo controle, sendo estatisticamente significante em C3A1 e C4A2. Contudo, não foi possível determinar efeito de lateralidade do P300 entre o hemisfério afetado e não-afetado.

Structural Brain Alterations in Individuals at Ultra-high Risk for Psychosis: A Review of Magnetic Resonance Imaging Studies and Future Directions

Individuals at ultra-high-risk (UHR) for psychosis have become a major focus for research designed to explore markers for early detection of and clinical intervention in schizophrenia. In particular, structural magnetic resonance imaging studies in UHR individuals have provided important insight into the neurobiological basis of psychosis and have shown the brain changes associated with clinical risk factors. In this review, we describe the structural brain abnormalities in magnetic resonance images in UHR individuals. The current accumulated data demonstrate that abnormalities in the prefrontal and temporal cortex and anterior cingulate cortex occur before illness onset. These regions are compatible with the regions of structural deficits found in schizophrenia and first-episode patients. In addition, the burgeoning evidence suggests that such structural abnormalities are potential markers for the transition to psychosis. However, most findings to date are limited because they are from cross-sectional rather than longitudinal studies. Recently, researchers have emphasized neurodevelopmental considerations with respect to brain structural alterations in UHR individuals. Future studies should be conducted to characterize the differences in the brain developmental trajectory between UHR individuals and healthy controls using a longitudinal design. These new studies should contribute to early detection and management as well as provide more predictive markers of later psychosis.

Gray, White Matter Concentration Changes and Their Correlation with Heterotopic Neurons in Temporal Lobe Epilepsy

OBJECTIVE: To identify changes in gray and white matter concentrations (GMC, WMC), and their relation to heterotopic neuron numbers in mesial temporal lobe epilepsy (mTLE). MATERIALS AND METHODS: The gray matter or white matter concentrations of 16 left and 15 right mTLE patients who achieved an excellent surgical outcome were compared with those of 24 healthy volunteers for the left group and with 23 healthy volunteers for the right group, by optimized voxel-based morphometry using unmodulated and modulated images. A histologic count of heterotopic neurons was obtained in the white matter of the anterior temporal lobe originating from the patients' surgical specimens. In addition, the number of heterotopic neurons were tested to determine if there was a correlation with the GMC or WMC. RESULTS: The GMCs of the left and right mTLE groups were reduced in the ipsilateral hippocampi, bilateral thalami, precentral gyri, and in the cerebellum. The WMCs were reduced in the ipsilateral white matter of the anterior temporal lobe, bilateral parahippocampal gyri, and internal capsules, but increased in the pons and bilateral precentral gyri. The heterotopic neuron counts in the left mTLE group showed a positive correlation (r = 0.819, p < 0.0001) with GMCs and a negative correlation (r = -0.839, p < 0.0001) with WMCs in the white matter of the anterior temporal lobe. CONCLUSION: The present study shows the abnormalities of the cortico-thalamo-hippocampal network including a gray matter volume reduction in the anterior frontal lobes and an abnormality of brain tissue concentration in the pontine area. Furthermore, heterotopic neuron numbers were significantly correlated with GMC or WMC in the left white matter of anterior temporal lobe.

Interictal SPECT in the presurgical evaluation in epileptic patients with normal MRI or bilateral mesial temporal sclerosis / SPECT intercrítico na avaliação pré-cirúrgica de pacientes epiléticos com ressonância magnética normal ou esclerose mesial temporal bilateral

The aim of this study was to evaluate the sensitivity of interictal compared to ictal SPECT in the lateralization of the epileptogenic focus in refractory temporal lobe epilepsy (TLE) patients that present with normal magnetic resonance imaging (MRI) or bilateral mesial temporal sclerosis (MTS). Thirty patients with TLE, for whom MRI examinations were normal or who presented with bilateral MTS, were retrospectively studied. Using a confidence interval of 95 percent and a level of significance for p-value <0.05, an estimated agreement rate of 73 percent with a minimum agreement rate of 57 percent was calculated comparing interictal and ictal SPECTs. In conclusion the interictal SPECT is only useful when associated with the ictal SPECT and does not substitute it in the localization of epileptogenic areas in patients with normal MRI or bilateral MTS.

O objetivo deste estudo foi avaliar a sensibilidade do SPECT interictal, em relação ao ictal, na lateralização do foco epileptogênico, de pacientes com epilepsia refratária de lobo temporal (ELT) que apresentam ressonância magnética (RM) normal ou esclerose mesial temporal (EMT) bilateral. Foram estudados retrospectivamente 30 pacientes com ELT, nos quais os exames de RM eram normais ou apresentavam EMT bilateral. Avaliada a sensibilidade do SPECT interictal em relação ao ictal, obtivemos taxa estimada de acerto de 73 por cento com taxa mínima de acerto de 57 por cento, adotando intervalo de confiança de 95 por cento e índice de significância p<0,05. Conclui-se que o SPECT interictal é necessário apenas quando associado ao SPECT ictal, e não substitui a realização do ictal na localização da AE em pacientes com RM normal ou EMT bilateral.

MRI of Neurosyphilis Presenting as Mesiotemporal Abnormalities: a Case Report

The high signal intensities in bilateral mesiotemporal lobes on T2-weighted images are typical findings of herpes encephalitis or paraneoplastic limbic encephalitis. We report a case of neurosyphilis with mesiotemporal involvement on MRI. Positive antibodies in the cerebrospinal fluid confirmed the diagnosis. The results suggest that neurosyphilis should be considered when MRI results indicate mesiotemporal abnormalities.

Histopathological findings in chronic pharmacoresistant temporal epilepsy: a pathognomonic combination of lesions maintaining neuron injury?

Progression and pharmacoresistance of epileptic seizures is clinically not yet well predicted and comprehensible. This was a pathological study of surgical specimens of resected temporal lobe and hippocampus in chronic pharmacoresistant temporal epilepsy, in order to determine any lesions that might play a role in the onset or in the maintenance of this type of epilepsy, and any lesions that might result in as wide a variety of lesions as have been reported in the different studies in the literature. This was a prospective histopathological study of successive mesial temporal and extrahippocampal structures removed from patients suffering from refractory epilepsy. Serial cut sections of 1.5 - 2 mm were studied between October 1997 and December 2004 in the Epilepsy Centre of Damascus University. A retrospective review was done later. Sixty-six consecutive surgical specimens from 66 patients with refractory epilepsy lasting for 1 - 32 years [mean = 16.2 years] were received and studied. Our series included 33 males and 33 females [2 - 45 years; average 22 years]. Pathological study revealed some constant lesions observed in all cases: signs of neuronal injury with cell lysis, apoptosis followed by neuronal loss, cortical dysplasia/ dysgenesis, hippocampal and temporal gliosis and focal degenerative cystic changes. Other observations were as follows: neuroglial tumours and malformations [20 cases, 30%], subependymal cortical heterotopia [13 cases, 20%], gyral fusion [16 cases, 24%] with abnormal elongation of the sulcus in [6 cases 9%], inflammation [10 cases, 15%], vascular tumours/ malformations [5 cases, 7.5%], gliomas [5 cases, 7.5%], severe atrophy [2 cases, 3%], small meningeal nodule [1 case, 1.5%], and old haemorrhage [1 case, 1.5%].In this series, a large variety of lesions were found with constant signs of neuronal injury and loss. A presumable epileptogenic focus was found in many cases [58%], and the multiplicity and multifocality of lesions were well documented. A good understanding of the sequencing of the processes leading to cell injury might contribute in the prevention of progression of epileptic seizure in previously susceptible patients