Bilateral ictal EEG is associated with better memory outcome after hippocampal sclerosis surgery.

OBJECTIVE: To compare memory outcomes after surgery for unilateral hippocampal sclerosis (HS)-associated epilepsy in patients with unilateral and bilateral ictal electrographic involvement. METHODS: We prospectively evaluated HS patients, aged 18-55 years and IQ ≥70. Left (L) and right (R) surgical groups underwent noninvasive video-EEG monitoring and Wada test. We classified patients as Ipsilateral if ictal EEG was restricted to the HS side, or Bilateral, if at least one seizure onset occurred contralaterally to the HS, or if ictal discharge evolved to the opposite temporal region. Patients who declined surgery served as controls. Memory was evaluated on two occasions with Rey Auditory-Verbal Learning Test and Rey Visual-Design Learning Test. Baseline neuropsychological test scores were compared between groups. Pre- and postoperative scores were compared within each group. Reliable change index Z-scores (RCI) were obtained using controls as references, and compared between surgical groups. RESULTS: We evaluated 64 patients. Patients were classified as: L-Ipsilateral (9), L-Bilateral (15), L-Control (9), R-Ipsilateral (10), R-Bilateral (9), and R-Control (12). On preoperative evaluation, memory performance did not differ among surgical groups. Right HS patients did not present postoperative memory decline. L-Ipsilateral group presented postoperative decline on immediate (P = 0.036) and delayed verbal recall (P = 0.011), while L-Bilateral did not decline. L-Ipsilateral had lower RCI Z-scores, indicating delayed verbal memory decline compared to L-Bilateral (P = 0.012). SIGNIFICANCE: Dominant HS patients with bilateral ictal involvement presented less pronounced postoperative verbal memory decline compared to patients with exclusive ipsilateral ictal activity. Surgery was indicated in these patients regardless of memory impairment on neuropsychological testing, since resection of the left sclerotic hippocampus could result in cessation of contralateral epileptiform activity, and, therefore, improved memory function.

Contralateral interictal and ictal EEG epileptiform activity accentuate memory impairment in unilateral mesial temporal sclerosis patients.

OBJECTIVE: Memory impairment is a recognized complication of mesial temporal sclerosis (MTS). Epileptiform activity may negatively impact on cognition. We evaluated the impact of contralateral EEG involvement on memory in unilateral MTS (uMTS) patients. METHOD: Retrospective review of 121 right-handed uMTS patients (69 left) evaluated with prolonged video-EEG and verbal and nonverbal memory tests (Rey Auditory Verbal Learning Test and Rey-Osterrieth Complex figure), with additional very delayed trials. Patients were classified according to ictal/interictal EEG findings and MTS side as left or right concordant or discordant. Thirty-nine normal individuals who underwent the same neuropsychological battery served as controls. RESULTS: Demographic, disease, and treatment features did not differ among groups. On the 7-day verbal memory free recall, left discordant performed significantly worse than controls and right concordant, recognized fewer words, and had more recognition errors than all other groups, including left concordant. For nonverbal memory, right discordant performed significantly worse than controls on delayed recall, and attained lower scores than other groups on immediate and 7-day recall, but this difference did not reach statistical significance. Left discordant had higher scores of memory complaints than controls and disclosed a trend toward accentuated memory impairment compared with the other groups over time. CONCLUSIONS: Our results suggest that contralateral electrographic involvement in uMTS was associated with more pronounced memory impairment for verbal material in left discordant patients, and to a lesser extent, for nonverbal material in right discordant patients. Left discordant group also had increased memory complaints. (PsycINFO Database Record

Contralateral ictal electrographic involvement is associated with decreased memory performance in unilateral mesial temporal sclerosis.

PURPOSE: To evaluate the effect of contralateral electrographic involvement on memory performance (measured by neuropsychological and Wada memory testing) in patients with epilepsy associated with unilateral mesial temporal sclerosis (MTS). METHODS: We studied 51 patients with medically-refractory epilepsy associated with unilateral MTS (27 women, 30/51, left MTS) submitted to prolonged non-invasive video-EEG monitoring and bilateral Wada testing. According to ictal electrographic involvement, patients were classified as: Contralateral ictal involvement, when one or more seizures evolved with rhythmic activity in the temporal region contralateral to the MTS or exclusive ipsilateral ictal involvement if all seizures showed ictal EEG activity exclusively on the MTS side. Wada testing involved a twelve-item memory paradigm. Wada memory asymmetry score was calculated for each patient subtracting the number of recalled items after injection on the lesion side from the number of recalled items after contralateral injection. Expected asymmetry (EA) was considered if Wada memory asymmetry>0, and Symmetrical or Reversed memory asymmetry (S-RA) when ≤ 0. Neuropsychological testing was applied in the 51 patients and in 40 healthy controls. Verbal Memory was evaluated with the Rey Auditory Verbal Learning Test (RAVLT), considering the number of recalled items on immediate recall after the initial five consecutive encoding trials (RAVLT 6), a post-interference delayed (30 min) recall (RAVLT 7), and recall after 7 days. Nonverbal memory was tested with Wechsler Memory Scale-III (WMS-III) Faces subtests 1 e 2. RESULTS: Groups did not differ in demographic, clinical and video-EEG monitoring variables. S-RA was observed more frequently in the group with contralateral ictal involvement (57.2% vs. 27.0%; p: 0.03). Logistic regression analysis considering demographic, clinical, hippocampal volume and video-EEG monitoring variables showed contralateral ictal involvement as the only independent variable associated with S-RA (coefficient=1.32, p=0.029, odds ratio 3.77; 95% CI 1.1-12.47). Additionally, the patient group with contralateral ictal EEG involvement displayed worse verbal and nonverbal memory scores compared to healthy controls. CONCLUSION: In this cohort of unilateral MTS patients, contralateral ictal involvement was associated with decreased memory performance on Wada and on neuropsychological testing.

The intracarotid etomidate Wada test: a 54-patient series.

Hemispheric language dominance and isolated hemispheric memory function evaluation can be undertaken with the intracarotid injection of a general anesthetic agent (Wada test). Amobarbital has been traditionally used as the anesthetic agent, but legal and commercial constraints limit its use. We evaluated the use of etomidate as an alternative agent for the Wada test in a series of 54 consecutive adult patients with mesial temporal sclerosis undergoing presurgical evaluation for epilepsy surgery. Language lateralization and hemispheric memory function evaluation were successfully achieved in all cases. Side effects (somnolence, tremor, and dystonia) were infrequent, minor, and transient and did not require interruption of the procedure. Etomidate appears to be a safe and effective alternative agent to amobarbital in the Wada test. Similarly to the amobarbital Wada test, the ability of the etomidate Wada test to predict postoperative memory decline remains unclear.

Low prevalence but high specificity of material-specific memory impairment in epilepsy associated with hippocampal sclerosis.

PURPOSE: Material-specific memory impairment is used as a lateralizing tool in the evaluation of temporal lobe epilepsy. Lateralizing ability of material-specific memory deficits in temporal lobe epilepsy remains controversial. METHODS: We studied memory impairment profiles of verbal and nonverbal memory deficits with eight memory subtests of four neuropsychological instruments (two verbal and two nonverbal) in 87 right-handed patients with epilepsy associated with unilateral mesial temporal sclerosis (MTS; 44 right - R, 43 left - L) and 42 controls, with an IQ >70, at least 8 years of education, and without comorbidities. KEY FINDINGS: Selective verbal memory impairment was noted in 11 of 43 or 25.6% of left MTS cases, with 82.2% specificity, whereas selective nonverbal memory impairment was noted in 11 of 42 or 26.2% of right MTS cases, with 92% specificity. Nonlateralizing profiles of memory performance were seen in the remaining 65 of 87 patients. Approximately half (46/87 or 52.9%) of the patients had intact memory function in both modalities, equally distributed between patients with right MTS (23/44) and left MTS (23/43). Global impairment of both memory types was seen in 12 of 87 or 13.8% of patients, equally distributed between the two groups (7/43 left and 5/44 right). SIGNIFICANCE: Lateralizing profiles of selective verbal and nonverbal memory deficits are highly specific for left and right MTS, although infrequently encountered in our patients. Nonlateralizing profiles predominated in this population. These findings suggest hemispheric asymmetry memory function, with complex functional interaction of the hippocampi, and possible compensatory mechanisms in the setting of a unilateral lesion.

Association among depression, cognitive impairment and executive dysfunction after stroke / Associação entre depressão, comprometimento cognitivo e disfunção executiva após acidente vascular cerebral

The relationship between depression and cognitive impairment, frequent after stroke, is complex and has not been sufficiently elucidated. Objective: To review the relationship between post-stroke depression and cognitive impairment. Methods: We performed a PubMed database search spanning the last ten years, using the terms post-stroke depression, cognitive dysfunction, cognitive impairment and neuropsychological tests. Our target studies were original quantitative studies that investigated the relationship between post-stroke depression (PSD) and cognitive impairment in stroke patients. Articles published in English, Spanish, Italian and Portuguese were considered. Selection criteria were the use of neuropsychological tests to assess cognitive function, and of either instruments to diagnose major depression, or scales to assess depressive symptoms, within the first three months after stroke. Results: Six original quantitative studies fulfilled the criteria. The prevalence of PSD within the first three months after stroke ranged from 22% to 31%. Incidence ranged from 25% to 27% and was evaluated in only two studies. PSD was associated with increased cognitive impairment. Cognitive impairment was reported in 35.2% to 87% of the patients. Post-stroke cognitive deficits were reported mostly in executive function, memory, language, and speed of processing. Conclusion: Executive dysfunction and depression occur in stroke survivors, are frequently coexistent, and also associated with worse stroke prognosis. Healthcare professionals need to address andprovide adequate treatment for depression and executive dysfunctions in stroke patients early in the first three monthsafter stroke. Future studies should evaluate the efficacy of programs evaluating the early detection and treatment of PSD and executive dysfunction in stroke survivors.

A depressão e o déficit cognitivo são frequentes após o acidente vascular cerebral. A relação entre as duas condições é complexa e não tem sido suficientemente elucidada. Objetivo: Fazer uma revisão da relação entre a depressão pós-AVC e prejuízo cognitivo. Métodos: Foi realizada uma pesquisa no banco de dados PubMed nos últimos dez anos. Nosso foco foi estudos quantitativos originais que investigaram a relação entre depressão e comprometimento cognitivoem pacientes com AVC. Os termos depressão, disfunção cognitiva, comprometimento cognitivo e testes neuropsicológicos foram usados para pesquisa. Foram considerados artigos publicados em Inglês, Espanhol, Italiano e Português. Os critérios de seleção foram o uso de testes neuropsicológicos para avaliar a função cognitiva com também o uso de instrumentos para diagnosticar a depressão maior ou escalas para avaliar sintomas depressivos nos primeiros três meses após o AVC. Resultados: Seis estudos quantitativos originais preencheram os critérios de seleção. A prevalência de depressão pós-AVC nos primeiros três meses após o AVC variou de 22% a 31%. A incidência de depressão pós-AVC variou de 25% a27% e foi avaliada apenas em dois estudos. A depressão pós-AVC esteve associada com comprometimento cognitivo maisacentuado. Disfunção cognitiva pós-AVC foi relatada em 35,2% a 87% dos pacientes. Déficits cognitivos pós-AVC foramencontrados principalmente em função executiva, memória, linguagem e velocidade de processamento. Conclusão: Adisfunção executiva e a depressão ocorrem em pacientes de AVC, sendo frequentemente concomitantes e associadas a um pior prognóstico. Os profissionais de saúde devem diagnosticar e fornecer um tratamento adequado para a depressão e disfunção executiva nos primeiros três meses após o AVC. Mais estudos devem avaliar a efetividade de programas de detecção precoce e tratamento da depressão e disfunção executiva pós-AVC.

Association among depression, cognitive impairment and executive dysfunction after stroke.

The relationship between depression and cognitive impairment, frequent after stroke, is complex and has not been sufficiently elucidated. OBJECTIVE: To review the relationship between post-stroke depression and cognitive impairment. METHODS: We performed a PubMed database search spanning the last ten years, using the terms post-stroke depression, cognitive dysfunction, cognitive impairment and neuropsychological tests. Our target studies were original quantitative studies that investigated the relationship between post-stroke depression (PSD) and cognitive impairment in stroke patients. Articles published in English, Spanish, Italian and Portuguese were considered. Selection criteria were the use of neuropsychological tests to assess cognitive function, and of either instruments to diagnose major depression, or scales to assess depressive symptoms, within the first three months after stroke. RESULTS: Six original quantitative studies fulfilled the criteria. The prevalence of PSD within the first three months after stroke ranged from 22% to 31%. Incidence ranged from 25% to 27% and was evaluated in only two studies. PSD was associated with increased cognitive impairment. Cognitive impairment was reported in 35.2% to 87% of the patients. Post-stroke cognitive deficits were reported mostly in executive function, memory, language, and speed of processing. CONCLUSION: Executive dysfunction and depression occur in stroke survivors, are frequently coexistent, and also associated with worse stroke prognosis. Healthcare professionals need to address and provide adequate treatment for depression and executive dysfunctions in stroke patients early in the first three months after stroke. Future studies should evaluate the efficacy of programs evaluating the early detection and treatment of PSD and executive dysfunction in stroke survivors.

A depressão e o déficit cognitivo são frequentes após o acidente vascular cerebral. A relação entre as duas condições é complexa e não tem sido suficientemente elucidada. OBJETIVO: Fazer uma revisão da relação entre a depressão pós-AVC e prejuízo cognitivo. MÉTODOS: Foi realizada uma pesquisa no banco de dados PubMed nos últimos dez anos. Nosso foco foi estudos quantitativos originais que investigaram a relação entre depressão e comprometimento cognitivo em pacientes com AVC. Os termos depressão, disfunção cognitiva, comprometimento cognitivo e testes neuropsicológicos foram usados para pesquisa. Foram considerados artigos publicados em Inglês, Espanhol, Italiano e Português. Os critérios de seleção foram o uso de testes neuropsicológicos para avaliar a função cognitiva com também o uso de instrumentos para diagnosticar a depressão maior ou escalas para avaliar sintomas depressivos nos primeiros três meses após o AVC. RESULTADOS: Seis estudos quantitativos originais preencheram os critérios de seleção. A prevalência de depressão pós-AVC nos primeiros três meses após o AVC variou de 22% a 31%. A incidência de depressão pós-AVC variou de 25% a 27% e foi avaliada apenas em dois estudos. A depressão pós-AVC esteve associada com comprometimento cognitivo mais acentuado. Disfunção cognitiva pós-AVC foi relatada em 35,2% a 87% dos pacientes. Déficits cognitivos pós-AVC foram encontrados principalmente em função executiva, memória, linguagem e velocidade de processamento. CONCLUSÃO: A disfunção executiva e a depressão ocorrem em pacientes de AVC, sendo frequentemente concomitantes e associadas a um pior prognóstico. Os profissionais de saúde devem diagnosticar e fornecer um tratamento adequado para a depressão e disfunção executiva nos primeiros três meses após o AVC. Mais estudos devem avaliar a efetividade de programas de detecção precoce e tratamento da depressão e disfunção executiva pós-AVC.

Prospective memory and mesial temporal epilepsy associated with hippocampal sclerosis.

Episodic memory impairment is commonly observed in patients with epilepsy associated with mesial temporal sclerosis (MTS). Prospective memory (PM) is a set cognitive abilities that allow future performance of a present intention, in response to time- or event-based evocation cues, that trigger the intended action at the appropriate time. PM has not been evaluated in mesial temporal sclerosis. We evaluated the role of right and left hippocampal lesions on performance in both the retrospective and prospective PM components in patients with epilepsy secondary to mesial temporal sclerosis and correlated with performance in traditional neuropsychological tests, as well as with self-perception of memory impairment. We tested the hypotheses that a hippocampal lesion impacts on the prospective components of PM, and that a left-sided lesion had a greater impact on performance in the prospective component of PM than a right-sided lesion. We evaluated PM in 26 patients with right MTS, 22 left MTS patients, and 26 age-gender and education matched controls. The prospective component of PM was impaired in both patient groups, with both a lesion (patients performed significantly worse in the PM battery) and laterality effect (left MTS patients performed significantly worse than right MTS patients in the PM battery). Performance in the prospective component of the PM battery correlated with long-term delay performance in episodic verbal memory and self-perception of memory impairment in the left MTS group. The retrospective component was impaired in left MTS patients. Impaired performance was not accounted for solely by depression, anxiety or an antiepileptic drug effect. We conclude that mesial temporal lobe structures, including the hippocampus, play an important role in both the prospective and retrospective components of PM processes in tasks involving long delay intervals.

Epilepsy syndromes associated with hypothalamic hamartomas.

PURPOSE: Hypothalamic hamartoma (HH) related epilepsy presents with gelastic seizures (GS), other seizure types and cognitive deterioration. Although seizure origin in GS has been well established, non-GS are poorly characterized. Their relationship with the HH and cognitive deterioration remains poorly understood. We analyzed seizure type, spread pattern in non-GS and their relationship with the epileptic syndrome in HH. METHODS: We documented all current seizure types in six adult patients with HH-epilepsy with video-EEG monitoring, characterized clinical-electrographic features of gelastic and non-gelastic seizures and correlated these findings with cognitive profile, as well as MRI and ictal SPECT data. RESULTS: Only four seizure types were seen: GS, complex partial (CPS), tonic seizures (TS) and secondarily generalized tonic-clonic seizures (sGTC). An individual patient presented either CPS or TS, but not both. GS progressed to CPS or TS, but not both. Ictal patterns in GS/TS and in GS/CPS overlapped, suggesting ictal spread from the HH to other cortical regions. Ictal SPECT patterns also showed GS/TS overlap. Patients with GS-CPS presented a more benign profile with preserved cognition and clinical-EEG features of temporal lobe epilepsy. Patients with GS-TS had clinical-EEG features of symptomatic generalized epilepsy, including mental deterioration. CONCLUSIONS: Video-EEG and ictal SPECT findings suggest that all seizures in HH-related epilepsy originate in the HH, with two clinical epilepsy syndromes: one resembling temporal lobe epilepsy and a more catastrophic syndrome, with features of a symptomatic generalized epilepsy. The epilepsy syndrome may be determined by HH size or by seizure spread pattern.