Esclerose hipocampal unilateral com registro subdural de crises temporais contralaterais: relato de caso / Unilateral hippocampal sclerosis with subdural strips in seizures from the contralateral temporal lobe: case report

INTRODUÇÃO: Pacientes com epilepsia temporal e esclerose hipocampal unilateral tem, na sua grande maioria das vezes, as suas crises e as alterações eletroencefalográficas interictais originando-se do lado da lesão. Mesmo alguns pacientes nos quais os registros de escalpo mostram as crises originando-se da região temporal contralateral à atrofia do hipocampo, registros invasivos têm mostrado que a região de início das crises é, na realidade, ipsilateral à atrofia. No entanto isso talvez não seja verdadeiro para todos pacientes. OBJETIVO: Nesse artigo é relatado uma paciente com atrofia hipocampal unilateral, mas cujas crises, tanto no escalpo quando com registros subdurais, mostram vir da região temporal contralateral. RESULTADO: A paciente tem atrofia hipocampal à direita mas cujo EEG interictal mostrava predomínio de descargas à esquerda, bem como crises vindo daí. O registro com strips subdurais mostrou origem das crises à esquerda. CONCLUSÃO: Possivelmente alguns pacientes com epilepsia temporal têm as crises vindo do hipocampo menos atrófico.

INTRODUCTION: Most patients with temporal lobe epilepsy and hippocampal sclerosis have the seizures and the interictal electroencephalographic abnormalities coming from the side of atrophic hippocampus. Even some patients on whom the seizures seem to arise from the contralateral temporal lobe, invasive recordings have shown that the seizures actually come from that atrophic side. But this may not be always the case. OBJECTIVE: We report a patient with a unilateral hippocampal atrophy and the seizures, seen both on the scalp as well with subdural strips, come from the contralateral temporal lobe. A patient with right hippocampal atrophy had most of the interictal discharges coming from the left temporal lobe, as well her seizures. Invasive recordings with subdural strips also showed seizures arising from the left temporal lobe. CONCLUSION: There might be some patients with temporal lobe epilepsy whose seizures come from the less.

Voxel-based Morphometry (VBM) Based Assessment of Gray Matter Loss in Medial Temporal Lobe Epilepsy: Comparison with FDG PET / 대한핵의학회잡지

PURPOSE: The aims of this study were to find brain regions in which gray matter volume was reduced and to show the capability of voxel-based morphometry (VBM) analysis for lateralizing epileptogenic zones in medial temporal lobe epilepsy (mTLE). The findings were compared with fluorodeoxyglucose positron emission tomography (FDG PET). MATERIALS AND METHODS: MR T1-weighted images of 12 left mTLE and 11 right mTLE patients were compared with those of 37 normal controls. Images were transformed to standard MNI space and averaged in order to create study-specific brain template. Each image was normalized to this local template and brain tissues were segmented. Modulation VBM analysis was performed in order to observe gray matter volume change. Gray matter was smoothed with a Gaussian kernel. After these preprocessing, statistical analysis was performed using statistical parametric mapping software (SPM99). FDG PET images were compared with those of 22 normal controls using SPM. RESULTS: Gray matter volume was significantly reduced in the left amygdala and hippocampus in left mTLE. In addition, volume of cerebellum, anterior cingulate, and fusiform gyrus in both sides and left insula was reduced. In right mTLE, volume was reduced significantly in right hippocampus. In contrast, FDG uptake was decreased in broad areas of left or right temporal lobes in left TLE and right TLE, respectively. CONCLUSIONS: Gray matter loss was found in the ipsilateral hippocampus by modulation VBM analysis in medial temporal lobe epilepsy. This VBM analysis might be useful in lateralizing the epileptogenic zones in medial temporal lobe epilepsy, while SPM analysis of FDG PET disclosed hypometabolic epileptogenic zones.

Measurement of Interuncal Distance in Mild Cognitive Impairment

OBJECTIVES: The hippocampal atrophy has been known to be an important biological marker for the early diagnosis of mild cognitive impairment (MCI). The aims of this study are to disclose the differerence in the interuncal distance (IUD) between MCI, dementia of the Alzheimer's type (DAT) and healthy aged controls, and to identify the affecting factors. METHODS: In transaxial plane, the IUDs at the level of the suprasellar cistern on the T1-weighted images on the brain MRI were measured in patients with MCI (N=30), those with DAT (N=34), and healthy aged controls (N=20). Furthermore, demographic data about age, sex, educational level as well as cerebrovascular factors were obtained by structured interviews and medical records, and the severity of cognitive disorders were assessed using the Mini-Mental Status Examination (MMSE), the Clinical Dementia Rating (CDR) and the Global Deterioration Scale (GDS). RESULTS: 1) The mean (+/-S.D.) IUD of DAT group (26.52+/-3.37 mm) was significantly different from that of healthy aged controls (24.35+/-2.91 mm)(p=0.044). However, there were no significant differences between IUD of MCI group (25.60+/-2.66 mm) and that of DAT group (p=0.483) as well as that of healthy aged controls and that of MCI group (p=0.363). 2) Variables such as age, sex, educational level, cerebrovascular risk factors and severity of cognitive disorder were not related to the IUD. CONCLUSIONS: The measurement of IUD on the brain MRI did not seem to be a helpful biological marker for the early detection of MCI in clinical practice.

Hippocampal Atrophy Pattern and Hippocampal Volume in Mesial Temporal Sclerosis: Correlation with Risk Factors and Surgical Outcome

BACKGROUND: Hippocampal sclerosis (HS) is the most common cause of temporal lobe epilepsy (TLE). However, the regional distribution pattern and volume loss of HS and its clinical significance are still controversial. We investigated the regional distribution of hippocampal atrophy (HA) and the volume loss of HS and correlated these data with several clinical factors including seizure risk factor and surgical outcome. METHODS:MRI volumetry was performed on 40 patients with TLE and pathologically proven HS and 20 control subjects using PACS system. The patterns of HA were categorized into diffuse and regional types. The clinical factors included were : age at onset, seizure duration, sex, history of febrile convulsion, and meningoencephalitis. MR volumetry data representing volume loss and pattern of HA were analyzed looking at surgical outcome and clinical factors. RESULTS: 1) The MRI volumetry of hippocampus was highly sensitive and specific (above 95%) for HS. 2) Diffuse HA involving both the hippocampal head and body was slightly more common (56%) than the regional pattern. Regional atrophy was usually found in the hippocampal body. 3) The history of meningitis/encephalitis was significantly associated with diffuse atrophy (p=0.034). 4) The age at seizure onset was correlated with the degree of HA (r=0.460, p=0.003). 5) The pattern and severity of HA were not related to surgical outcome. CONCLUSIONS: The variable patterns of HA exist in mesial temporal sclerosis. They may be related to various clinical factors and the underlying epileptogenic process.

Intractable Epilepsy associated with Neurocysticercosis: Perilesional Epileptogenic Features

BACKGROUND: Neurocysticercosis (NCC) is the most common parasitic disease of the CNS and seizures are the most frequent clinical manifestations of it. Although the medical treatment of NCC is effective, epilepsy surgery is still needed to treat refractory seizures. We investigated five cases with refractory seizures due to NCC to verify perilesional epileptogenic changes in NCC. METHOD: We included 5 intractable epilepsy patients who had epilepsy surgery and pathologically proven cysticercosis although serological tests were negative. A routine EEG and brain MRI were performed in all patients. Video scalp-EEG monitorings were done in 5 patients, including an invasive-EEG monitoring in one. We analyzed the relationships between semiology, brain MRI, interictal, and ictal EEG findings, pathologic features and surgical outcomes. RESULTS: All patients had abdominal or psychic aura, evolving into automotor seizure and then secondarily generalized tonic clonic seizures. Two patients often had only the aura. In brain MRI, four patients had showed NCC lesions in the mesial temporal area, and one had it in the basal occipital area. Hippocampal atrophy was also detected in 3 patients. Irritative and ictal onset zones on an EEG were located around the lesions. Pathologic findings confirmed hippocampal sclerosis in 3 patients and coritcal dyslamination and many single heterotopic neurons in the temporal lobe in 1 patient. Surgical outcomes showed 3 patients in class IA, 1 in class IC, and 1 in class IIB by Engel classification. CONCLUSIONS: Epileptic foci could be formed focally around the NCC lesion and hippocampal sclerosis frequently accompanied when the lesion was located near the mesial temporal structures. After verifying epileptic foci and lesion, epilepsy surgery had good surgical outcome.

Beck Depression Inventory in Temporal Lobe Epilepsy with Hippocampal Atrophy: Relation to Lesion Laterality

BACKGROUND: Depression is found more frequently in epileptic patients and tends to be more severe in those with temporal lobe epilepsy, than in patients with comparable chronic neurologic diseases or physical handicaps. The purposes of this study were to evaluate (1) the characteristics and frequency of depression in group of temporal lobe epileptic out-patients with hippocampal atrophy; (2) the relationship between depression and the laterality of hippocampal atrophy, and (3) the possible correlation between depression and the duration of epilepsy, sex, education, age, occupation, seizure frequency, and other seizure variables. METHODS: We included 40 temporal lobe epilepsy patients with unilateral hippocampal atrophy on MRI study. We used the Beck Depression Inventory to measure the level of depression. The results were compared with those of 50 normal controls. RESULTS: (1) Epilepsy patients with hippocampal atrophy indicated more severe depression than the normal controls. If we consider the cut-off score for depression as being more than 21 points of the Beck Depression Inventory score, then the frequency of depression in TLE with hippocampal atrophy would be 45% compared to the 14% in controls. (2) Occupation and seizure frequencies were factors related to severe depression. However, the age, age of onset, duration of illness, religion, education, and multi-drug therapy, were not related to the severity of depression. (3) Scores on the BDI questions representing mood symptoms were significantly higher in the left TLE group. However, the frequencies of those representing vegetative and somatic symptoms were not different between the two groups. Self-reproach symptoms increased equally in both temporal lobe epilepsy groups. (4) There were no clear associations between depressive disorders and the laterality of epileptic lesions in the TLE patients. CONCLUSIONS: We found no clear association between the affective disorders in epilepsy and the site of epileptic lesions.