Background: Conventional volumetric studies have shown that brain structures functionally and anatomically related to the hippocampus are smaller in patients with drug-refractory medial temporal lobe epilepsy (MTLE). Objectives: To determine the extent of gray matter atrophy in the brains of patients with MTLE and to examine the pattern of atrophy. Design: We performed a voxel-based morphometric study of 43 consecutive patients with unilateral drugrefractory MTLE (21 patients with right-sided MTLE and 22 patients with left-sided MTLE) whose magnetic resonance images showed signs of unilateral hippocampal atrophy. The data from the patients with MTLE were compared with the data from 49 healthy control subjects to identify differences between groups in gray matter concentration (GMC).

No abstract

VBM of BSI is a useful and objective method for detecting perfusion abnormalities in SLE patients, which is indicative of active CNS involvement. However, it is not helpful in differentiating the clinical sub-types of CNS involvement according to the ACR classification.

-O b j e c t i v e :To investigate the pattern of perfusion abnormalities in ictal and interictal brain perfusion SPECT images (BSI) from patients with temporal lobe epilepsy (TLE). Method: It was acquired interictal and ictal BSI from 24 patients with re f r a c t o ryTLE. BSIs were analyzed by visual inspection and statistical parametric mapping (SPM2). Statistical analysis compared the patients group to a control gro u p of 50 volunteers. The images from patients with left-TLE were left-right flipped. Results: It was not obs e rved significant perfusional diff e rences in interictal scans with SPM. Ictal BSI in SPM analysis revealed hyp e r p e rfusion within ipsilateral temporal lobe (epileptogenic focus) and also contralateral parieto-occipital region, ipsilateral posterior cingulate gyrus, occipital lobes and ipsilateral basal ganglia. Ictal BSI also showed areas of hypoperf u s i o n . Conclusion: In a group analysis of ictal BSI of patients with TLE, voxelwise analysis detects a network of distant regions of perfusional alteration which may play active role in seizure genesis and propagation.KEY WORDS: brain perfusion, SPECT, SPM, seizures, epilepsy.Análise estatística baseada em voxel do SPECT ictal revela um padrão de alteração perf u s i o n a l em pacientes com epilepsia de lobo temporal RESUMO -Objetivo: Investigar o padrão de anormalidades perfusionais no SPECT de perfusão cere b r a l (SPC) ictal e interictal na epilepsia de lobo temporal (ELT ) . Método: Foram realizados SPCs ictal e interictal de 24 pacientes com ELT que foram analisados visualmente e com o statistical parametric mapping (SPM2). A análise estatística comparou o grupo de pacientes versus um grupo controle de 50 voluntários. Resultados: Na análise do SPM não foram observadas diferenças significativas no grupo de SPC interictal. No grupo de SPC ictal o SPM revelou hiperperfusão no lobo temporal ipsilateral (foco epileptogênico) e também na região parieto-occipital contralateral, porção posterior do cíngulo ipsilateral, lobos occipitais e núcleos da base ipsilateral. O SPC ictal também mostrou áreas de hipoperf u s ã o . Conclusão: Em uma análise de grupo do SPC ictal de pacientes com ELT, a análise baseada em voxel detecta uma rede de alteração perfusional em regiões distantes que pode ter uma função ativa na origem e propagação das crises. PALAVRAS-CHAVE: Perfusão cerebral, SPECT, SPM, crises epilépticas, epilepsia.Epilepsy affects 0.5 to 1% of the world populat i o n 1 . Anti-epileptic drugs successfully control seiz u res in most patients with epilepsy. Surgical tre a tment of epilepsy is a therapeutic option for those patients who do not achieve a seizure -f ree status with medication and have a focal brain lesion accounting for the origin of seizures. Medial temporal lobe epilepsy (TLE) is both the most fre q u e n t f o rmof epilepsy as well as the form that accounts for the majority of epilepsy patients submitted to s u rg e ry, which is perf o rmed by hippocampal removal. Histological analysis of the specimen re s ...