RESUMO
The cellular prion protein, encoded by Prnp gene, is involved in neuroprotection, neuroplasticity and neurodevelopment. The variant allele Valine at codon 129 of the Prnp was associated with decreased brain volume in healthy volunteers and schizophrenic patients. We investigate the association between the cerebellum volume and the presence of variant allele Valine at codon 129 of the Prnp gene in patients with mesial temporal lobe epilepsy related to hippocampal sclerosis (MTLE-HS). The Prnp coding sequence was determined in 41 refractory MTLE-HS patients. The cerebellum volume corrected by the intracranial volume of patients with the normal Prnp genotypes was compared with that of patients presenting the variant alleles at codon 129. Twenty patients showed the Met129Met genotype, 16 showed Met129Val, and 5 had Val129Val. There were no association among clinical, demographic, electrophysiological, antiepileptic drugs used, and the presence of the Prnp variant alleles. The presence of Prnp variant allele at codon 129 was not associated with the analyzed cerebellum volume. Prnp variant alleles at codon 129 are not associated with cerebellum volume in patients with refractory MTLE-HS.
Assuntos
Cerebelo/patologia , Epilepsia do Lobo Temporal/genética , Epilepsia do Lobo Temporal/patologia , Príons/genética , Adulto , Alelos , Anticonvulsivantes/uso terapêutico , Encéfalo/patologia , Eletroencefalografia , Epilepsia do Lobo Temporal/tratamento farmacológico , Epilepsia do Lobo Temporal/fisiopatologia , Feminino , Variação Genética , Humanos , Imageamento por Ressonância Magnética , Masculino , Tamanho do Órgão , Proteínas Priônicas , Convulsões/tratamento farmacológico , Convulsões/genética , Convulsões/patologia , Convulsões/fisiopatologiaRESUMO
Patients with left mesial temporal lobe epilepsy (MTLE) have deficits in verbal memory processes, while patients with right MTLE have visuospatial memory impairment. However, atypical cognitive phenotypes among patients with MTLE may occur. In this study, we analyzed preoperative memory deficits in a cohort of 426 right-handed patients with unilateral MTLE. We also evaluated the cognitive outcome after anterior temporal lobectomy (ATL) of patients with atypical profiles in comparison with those with typical memory profile. We found that 25% of our patients had a typical cognitive profile, with verbal memory deficits associated with left side hippocampal sclerosis (HS) and visuospatial memory deficits associated with right side HS. However, 75% of our patients had atypical memory profiles. Despite these atypical profiles, patients submitted to right ATL had no significant cognitive deficit after surgery. In patients submitted to left ATL, the higher the presurgical scores on verbal memory and naming tests, the higher the cognitive decline after surgery.
Assuntos
Transtornos Cognitivos/diagnóstico , Transtornos Cognitivos/etiologia , Epilepsia do Lobo Temporal/complicações , Lateralidade Funcional/fisiologia , Transtornos da Memória/diagnóstico , Transtornos da Memória/etiologia , Adulto , Análise de Variância , Eletroencefalografia , Epilepsia do Lobo Temporal/cirurgia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neuroimagem , Testes Neuropsicológicos , Procedimentos Neurocirúrgicos , Percepção Espacial/fisiologia , Gravação em VídeoRESUMO
The absence of the adhesio interthalamica (AI; also called interthalamic adhesion or massa intermedia) and the presence of a large cavum septum pellucidum (CSP) later in life have been related to neurodevelopmental alterations and have not been systematically investigated in epilepsy to date. This study carried out a MRI evaluation of the AI and CSP in a large sample with mesial temporal lobe epilepsy (MTLE). A total of 179 patients, classified according to the side of the epileptogenic focus, and 156 age- and sex-balanced healthy controls were assessed. Between-group comparisons of the prevalence and length of both AI and CSP were conducted. Neuropsychological assessments were also performed in 160 MTLE patients. The patients exhibited reduction in the AI prevalence (P < 0.05; FDR-uncorrected) and length (P < 0.05; FDR-corrected) when compared to controls. Patients without AI showed lower scores in a proportion of neuropsychological tests than patients with AI. No CSP differences were found between MTLE patients and controls. These results support that AI anomalies have clinical significance in MTLE, as well as indicate that neurodevelopmental alterations may be implicated in this disorder.
Assuntos
Epilepsia Resistente a Medicamentos/diagnóstico por imagem , Epilepsia do Lobo Temporal/diagnóstico por imagem , Septo Pelúcido/diagnóstico por imagem , Tálamo/diagnóstico por imagem , Adulto , Epilepsia Resistente a Medicamentos/psicologia , Epilepsia do Lobo Temporal/psicologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Testes Neuropsicológicos , Tamanho do Órgão , Esclerose/diagnóstico por imagem , Esclerose/psicologia , Septo Pelúcido/crescimento & desenvolvimento , Tálamo/crescimento & desenvolvimentoRESUMO
BACKGROUND: Where neurocysticercosis (NCC) is endemic, chronic calcified neurocysticercosis (cNCC) can be observed in patients with mesial temporal lobe epilepsy associated with hippocampal sclerosis (MTLE-HS). Considering that both disorders cause recurrent seizures or cognitive impairment, we evaluated if temporal lobectomy is cognitively safe and effective for seizure control in MTLE-HS plus cNCC. METHODS: Retrospective cohort study of neuropsychological profile and surgical outcome of 324 MTLE-HS patients submitted to temporal lobectomy, comparing the results according to the presence or absence of cNCC. FINDINGS: cNCC occurred in 126 (38.9%) of our MTLE-HS patients, a frequency higher than expected, more frequently in women than in men (O.R.â=â1.66; 95% C.I.â=â1.05-2.61; pâ=â0.03). Left-side (but not right side) surgery caused impairment in selected neuropsychological tests, but this impairment was not accentuated by the presence of cNCC. Ninety-four (74.6%) patients with MTLE-HS plus cNCC and 153 patients (77.3%) with MTLE-HS alone were Engel class I after surgery (O.R.â=â1.16; 95% C.I.â=â0.69-1.95; pâ=â0.58). However, the chances of Engel class IA were significantly lower in MTLE-HS plus cNCC than in patients with MTLE-HS alone (31.7% versus 48.5%; O.R.â=â2.02; 95% C.I.â=â1.27-3.23; pâ=â0.003). Patients with MTLE-HS plus cNCC showed higher rates of Engel class ID (15.1% versus 6.6%; O.R.â=â2.50; 95% C.I.â=â1.20-5.32; pâ=â0.012). INTERPRETATION: cNCC can be highly prevalent among MTLE-HS patients living in areas where neurocysticercosis is endemic, suggesting a cause-effect relationship between the two diseases. cNCC does not add further risk for cognitive decline after surgery in MTLE-HS patients. The rates of Engel class I outcome were very similar for the two groups; however, MTLE-HS plus cNCC patients achieved Engel IA status less frequently, and Engel ID status more frequently. Temporal lobectomy can be safely performed in most patients with MTLE-HS plus cNCC without affecting cognitive outcome. Long-term surgical seizure control in MTLE-HS plus cNCC is still satisfactory, as long as selected patients remain under medication.
Assuntos
Cognição , Epilepsia do Lobo Temporal/fisiopatologia , Epilepsia do Lobo Temporal/cirurgia , Hipocampo/patologia , Neurocisticercose/complicações , Adulto , Criança , Estudos de Coortes , Tomada de Decisões , Epilepsia do Lobo Temporal/complicações , Epilepsia do Lobo Temporal/patologia , Feminino , Humanos , Masculino , Esclerose/complicações , Resultado do TratamentoRESUMO
Cognitive impairment has long been recognized in people with medically refractory epilepsies. Mesial temporal lobe epilepsy related to hippocampal sclerosis (MTLE-HS), the most common surgically remediable epileptic syndrome, has been associated with a cellular prion protein (PrPc) gene (Prnp) variant allele at codon 171. The polymorphism consisting of a methionine-for-valine substitution at codon 129 has been associated with early cognitive deterioration in elderly people and patients with Down syndrome. The same variant allele in homozygosis (V129V) has been associated to a lower long-term memory in healthy humans. PrPc mediates several processes related to neuroplasticity, and its role in cognitive processes remains unknown. In this study, we evaluated the genetic contribution of Prnp alleles to cognitive performance in patients with MTLE-HS. Cognitive performance, measured with 19 neuropsychological tests, of patients with refractory MTLE-HS with the normal Prnp genotypes was compared with that of patients with the variant alleles at codons 129 and 171. With the effects of clinical, demographic, electrophysiological, and neuroimaging variable interactions controlled by multiple linear regression analysis and adjustment for multiple test comparisons, the presence of Prnp variant alleles was found not to be significantly associated to cognitive performance of patients with MTLE-HS. The presence of variant alleles at codons 129 and 171 is not associated to cognitive performance of patients with refractory MTLE-HS.