Anterior temporal lobectomy combined with anterior corpus callosotomy in patients with temporal lobe epilepsy and mental retardation

AimsTo investigate the surgical outcomes of anterior corpus callosotomy (aCCT) combined with anterior temporal lobectomy (ATL) in patients with intractable temporal lobe epilepsy (TLE) and mental retardation (MR).MethodsSixty patients with TLE and MR were carefully selected and randomly divided into two equal groups: ATL and aCCT, in which they were treated with ATL or ATL combined with aCCT, respectively. Surgical outcomes, including seizure control, IQ and quality of life (QOL) changes, as well as complications were recorded and analyzed 2 years after operation.ResultsSeizure-free status had been achieved in 66.7% of all patients. The aCCT group had higher percentage in Engle Classes I–II than the ATL group (96.7% vs. 80.0%, P < 0.05). 56.7% of patients in ATL group and 63.3% in aCCT group had improved full scale IQ (FIQ) after surgery, while the decline of FIQ in aCCT group was less than that of ATL group (3.3% vs. 30.0%). Compared with pre-operative score, the mean post-operative score of performance IQ in aCCT group had improved. Significant difference in QOL change had been found between two groups (P < 0.001). 73.7% of patients in aCCT group had their QOL improved with no long-term complications.ConclusionsATL combined with aCCT can improve QOL and performance IQ in patients with TLE and MR.     

Predictors of language skills in the long term after pediatric epilepsy surgery

ObjectiveThe objective of this study was to evaluate language skills in a heterogeneous cohort of patients who underwent or were considered for epilepsy surgery in childhood 4–11 years earlier. The few existing studies that have evaluated cognitive function in the long term after surgery have examined intelligence and memory.MethodParticipants were 97 patients, of whom 61 underwent surgery. They completed standardized tests of picture naming, vocabulary, letter fluency, semantic fluency and intelligence at baseline and, on average, 7 years later.ResultsAmong all patient groups, scores across language tasks were similar at baseline and follow-up. Language skills were largely independent of surgical status but were associated with seizure control. Seizure freedom and/or a longer proportion of life without seizures were associated with higher scores across all language tasks at follow-up. However, few patients showed meaningful improvements or deterioration at the individual level. Older age at epilepsy onset, higher IQ, and higher baseline scores were associated with higher follow-up scores on all language tasks. Localization and lateralization of epileptogenic foci and language lateralization were associated with higher scores on some language tasks at follow-up. Most of these variables were also predictive of change in scores over time on some of the language tasks.SignificanceLanguage skills largely remained similar at baseline and follow-up. Seizure freedom was associated with a modest advantage at the group level, and no significant change at the individual level, suggesting an abnormal neural substrate or epileptic activity prior to seizure control may hinder the long-term capacity for improvement, even in the absence of seizure activity.     

Academic achievement one year after resective epilepsy surgery in children

PurposeFew studies have examined the academic functioning of children following pediatric epilepsy surgery. Although intellectual functioning has been more thoroughly investigated, children with epilepsy may experience additional difficulties with academic skills. This study examined the academic outcomes of a cohort of children who underwent pediatric epilepsy surgery on an average 1.2 (standard deviation [SD]: 0.3) years prior.MethodsParticipants were 136 children (mean age: 14.3 years, [SD]: 3.7 years) who had undergone resective epilepsy surgery. Academic functioning was assessed presurgery and postsurgery using standardized tests of reading, reading comprehension, arithmetic, and spelling.ResultsAt baseline, 65% of the children displayed low achievement (1 SD below test mean), and 28% had underachievement (1 SD below baseline IQ) in at least one academic domain. Examining change over time revealed that reading, numeral operations, and spelling significantly declined among all patients; seizure freedom at follow-up (attained in 64% of the patients) did not influence this relationship. Reading comprehension and IQ remained unchanged. Similar findings were found when examining patients with a baseline IQ of ≥ 70 and when controlling for IQ. Regression analyses revealed that after controlling for IQ, demographic and seizure-related variables were not significantly associated with academic achievement at follow-up.ConclusionsResults show baseline academic difficulties and deteriorations following surgery that go beyond IQ. Further investigations are required to determine whether the observed deteriorations result from the development of the child, the course of the disorder, or the epilepsy surgery itself. Long-term studies are warranted to identify the progression of academic achievement and whether the observed deteriorations represent a temporal disruption in function.     

Predictors of intellectual functioning after epilepsy surgery in childhood: The role of socioeconomic status

ObjectiveThe objective of this study was to evaluate the association between socioeconomic status and intellectual functioning in children with medically refractory epilepsy, before and after resective epilepsy surgery. Family environment is a strong contributor to cognitive development in children and has been recently shown to play a significant role in intellectual outcome after surgery in children with epilepsy.MethodsOne hundred children who had undergone resective epilepsy surgery and completed preoperative and postoperative assessments of IQ as part of clinical care were included in the study. We evaluated the impact of epilepsy-related variables, income quintile, and residence location on IQ.ResultsGreater improvements in IQ after surgery were associated with an older age at surgery (β = .235, p = .018). Higher IQ scores at follow-up were associated with an older age of seizure onset (β = .371, p < .001), older age at surgery (β = .356, p < .001), unilobar epileptogenic focus (β = .394, p < .001), and mesial temporal sclerosis (β = .338, p = .001) or tumor (β = .457, p < .001) in comparison with malformation of cortical development; age at seizure onset did not remain as a significant predictor in multivariable regression analysis. Income quintile, residence location, seizure control, and antiepileptic medication use were not significant predictors.ConclusionsEpilepsy-related variables were the strongest predictors of IQ and postoperative change in IQ. We were unable to identify a significant association between IQ and socioeconomic status. Future research should evaluate the impact of multiple aspects of family environment.     

Decline in word-finding: The objective cognitive finding most relevant to patients after mesial temporal lobe epilepsy surgery

PurposeThe purpose of this study was to investigate the following: i) the objective impairment in neuropsychological tests that were associated with the subjective perception of cognitive function decline in Brazilian patients who underwent mesial temporal lobe epilepsy (MTLE) surgery and ii) the predictive variables for those impaired objective neuropsychological tests.MethodsForty-eight adults with MTLE (27 right HS and 23 male) were divided according to their perception of changes (Decline or No-decline) of cognitive function domain of the QOLIE-31 questionnaire applied before and 1 year after the ATL. The mean (SD) of changes in the raw score difference of the neuropsychological tests before and after the ATL was compared between Decline and No-decline groups. Receiver Operating Characteristic curves, sensitivity, specificity, and predictive values were used to assess the optimum cutoff points of neuropsychological test score changes to predict patient-reported subjective cognitive decline.Key findingsSix (12.5%) patients reported a perception of cognitive function decline after ATL. Among the 25 cognitive tests analyzed, only changes in the Boston Naming Test (BNT) were associated with subjective cognitive decline reported by patients. A reduction of ≥ 8 points in the raw score of BNT after surgery had 91% of sensitivity and 45% specificity for predicting subjective perception of cognitive function decline by the patient. Left side surgery and age older than 40 years were more associated with an important BNT reduction with overall accuracy of 91.7%, 95% predictive ability for no impairment, and 75% for impairment of cognitive function.SignificanceImpairment in word-finding seems to be the objective cognitive finding most relevant to Brazilian patients after mesial temporal lobe epilepsy surgery. Similar to American patients, the side of surgery and age are good predictors for no decline in the BNT, but shows a lower accuracy to predict its decline. If replicated in other populations, the results may have wider implications for the surgical management of patients with drug-resistant MTLE.     

Long term outcome in children affected by absence epilepsy with onset before the age of three years

ObjectiveThe goal of this study was to define the long-term outcome of absence epilepsy presenting before the age of 3 years.MethodsWe retrospectively studied the medical records of 40 children from eight neuropediatric centers in Italy with respect to the personal and family histories of epilepsy or febrile seizures, time of follow-up, cognitive functions, treatment, and outcome.ResultsForty patients were enrolled in this study. They all fulfilled the criteria for absence epilepsy with 3-Hz spike–wave complexes on the EEG, normal neurological examination, and no other seizures types. Seizure onset occurred between 24.1 and 36.0 months. There was a family history of epilepsy in 28%, and of febrile seizures in 13%. Thirty-three patients were treated with valproic acid (VPA), mostly used in monotherapy (26 patients) or in association with ethosuximide. At final follow-up, 33 patients were seizure free and 29 had normal EEGs. Thirty-four patients had a normal intelligence quotient (IQ), whereas 6 had a decreased IQ, mainly associated with poor control of seizures.ConclusionIn our series, absence seizures presenting before the age of 3 appeared to have quite a good long-term clinical prognosis; the neuropsychological outcome was comparable to that of childhood epilepsy presenting after 3 years of age.     

Is reoperation an option for patients with temporal lobe epilepsy after failure of surgery?

PurposeEpilepsy surgery is the most efficacious therapeutic modality for patients with medically refractory focal epilepsies, but surgical failures remain a challenge to the epilepsy treatment team. The aim of present study was to evaluate the postoperative outcome of patients who underwent reoperation after a failed epilepsy surgery on the temporal lobe.MethodsWe systematically analyzed the results of comprehensive preoperative evaluations before the first surgery, and before and after reoperation in 17 patients with drug resistant temporal lobe epilepsies.ResultsOverall, 13 of 17 patients (76.5%) improved after reoperation: five patients (29.4%) were completely seizure free after reoperation (median duration 60 months, range 12–72); six patients (35.3%) were seizure free at least 12 month before observation points (median duration 120.5 months, range 35–155) and two patients (11.8%) had a decrease in seizure frequency. Four patients (23.5%) remained unchanged with respect to seizure frequency and severity. There was no correlation between the improvement in seizure outcome after reoperation and other clinical data except of the history of traumatic brain injury (TBI). The patients who had no history of TBI improved after reoperation, compared to patients with TBI (p = 0.044). The postoperative seizure outcome of patients with incongruent Video-EEG results before the first surgery (p = 0.116) and before reoperation (p = 0.622) was not poorer compared to patients with congruent Video-EEG results.ConclusionsReoperation can considerably improve the operative outcome of the first failed epilepsy surgery in patients with drug resistant temporal lobe epilepsies. Epilepsy centres should be encouraged to report the results of failed epilepsy surgeries.     

The neuropsychological outcome of pediatric patients with refractory epilepsy treated with VNS — A 24-month follow-up in Taiwan

ObjectivesMultiple studies have reported the benefits of vagus nerve stimulation (VNS) on neuropsychological outcomes. The aim of this study was to investigate how VNS affects cognition and psychosocial adjustment in children with refractory epilepsy (RE), and to determine the efficacy of VNS in a Taiwanese population.MethodsWe conducted a one-group pretest–posttest study on pediatric patients with RE. The study comprised 19 males and 18 females, all aged < 18 years. We recorded seizure frequency at 3, 12, and 24 months after VNS device implantation. Intelligence quotients (IQ) were assessed using the Wechsler Intelligence Scale for Children — IV. The Parental Stress Index (PSI) scores were evaluated by a pediatric psychologist.ResultsVagus nerve stimulation device implantation significantly reduced seizure frequency at 3, 12 and 24 months, especially in young children (< 12 years). No significant improvement in IQ test performance was observed, though there were significant improvements in the PSI, especially in young children.ConclusionsVagus nerve stimulation device implantation does not significantly improve cognition function, but it does significantly reduce seizure frequency and stress in parent–child relationships, especially in young children (< 12 years). These findings suggest that VNS should be considered as an alternative therapy for patients proven to have seizures that are medically refractory, especially those younger than 12 years of age.     

The Wada memory test and prediction of outcome after anterior temporal lobectomy

We reviewed the records of 77 Chinese-speaking adult patients to investigate the relationship between the Wada memory test and outcomes after anterior temporal lobectomy (ATL). The ipsilateral memory scores, contralateral memory scores and Wada asymmetry index (WAI) were calculated to evaluate their relationships with seizure and cognitive outcomes. The seizure outcomes did not correlate with the unilateral memory scores or the WAI. Patients who had a smaller WAI tended to have a post-operative decline in verbal intelligence quotient (VIQ) (odds ratio: 13.54, 95% confidence interval: 1.17–156.11, p = 0.037). The seven patients who failed the Wada memory test after ipsilateral injection had a higher percentage of VIQ deterioration than the 70 who passed (p = 0.039). However, no patient displayed global amnesia after surgery. The Wada memory test was a predictor for post-operative VIQ changes in our study. Patients who failed the Wada memory test still benefitted from the ATL and showed good seizure outcomes.     

Memory outcome following left anterior temporal lobectomy in patients with a failed Wada test

PurposeThis study aimed to compare the memory outcome following left anterior temporal lobectomy (ATL) between patients with a failed Wada test and patients who passed the Wada test.MethodsFrom 1996 to 2002, we performed the Wada test on all patients with unilateral left mesial temporal lobe epilepsy with hippocampal sclerosis (MTLE-HS) and concordant electroclinical data before ATL. We used a 12-item recognition paradigm for memory testing and awarded a score of + 1 for each correct response and − 0.5 for each incorrect response. No patient was denied surgery on the basis of Wada scores. We assessed cognitive and memory functions using the Wechsler Adult Intelligence Scale and the Wechsler Memory Scale preoperatively and at one year after ATL. We compared the number of patients who showed decline in memory scores, as per the published reliable change indices, between the patients with a failed Wada test and the patients who passed the Wada test.ResultsOut of the 116 eligible patients with left MTLE-HS, 88 underwent bilateral Wada test, while 28 underwent ipsilateral Wada test. None of them developed postoperative amnesia. Approximately, one-third of patients with a failed Wada memory test when the failure was defined as a contralateral score of < 4, as an ipsilateral score of > 8, and as an asymmetry score of < 0. The patients with Wada memory failure had a longer pre-ATL duration of epilepsy (p < 0.003). The memory and quality-of-life outcomes did not differ between the group with a failed Wada memory test and the group who passed the Wada memory test. The results remained the same when analyses were repeated at various other cutoff points.ConclusionThe patients with left MTLE-HS with concordant electroclinical, MRI, and neuropsychological data should not be denied ATL solely on the basis of Wada memory test results.     

Preoperative depressive symptoms predict postoperative seizure outcome in temporal and frontal lobe epilepsy

ObjectiveRecent research has pointed to the possibility of a bidirectional relationship between seizure frequency in epilepsy and depressive symptoms. The study described here investigated the relationship between preoperative depressive symptomatology and postoperative seizure outcome in a sample of patients with temporal (TLE) and frontal (FLE) lobe epilepsy.MethodsA retrospective analysis was conducted on the data from 115 eligible patients with TLE (N = 97) and FLE (N = 18) and resections limited to one cortical lobe who were evaluated preoperatively and 1 year after epilepsy surgery with respect to depressive symptoms (Beck Depression Inventory, BDI) and seizure outcome. The latter was assessed in terms of actual total seizure frequency as well as a dichotomous variable (seizure free vs. not seizure free) for the 1-year outcome. Repeated-measures analyses of variance and regression analyses were applied.ResultsSeizure-free patients had significantly lower BDI scores preoperatively as well as postoperatively than patients who were not seizure free. In the regression analyses, the preoperative BDI score was a significant predictor of postoperative seizure frequency as well as seizure freedom. When only patients with TLE were analyzed, the results for the association between preoperative BDI and postoperative seizure frequency and seizure freedom remained consistent.ConclusionThe present results provide evidence for a statistical bidirectionality of the relationship between depressive symptoms and postoperative seizure status in a mixed sample of patients with TLE and FLE. Possible reasons for this bidirectional association include an underlying common pathology in both depression and epilepsy, for example, structural changes or functional alterations in neurotransmitter systems.     

Cognitive outcome after stereotactic amygdalohippocampectomy

PurposeWe sought to determine the neuropsychological outcome after stereotactic radiofrequency amygdalohippocampectomy performed for intractable mesial temporal lobe epilepsy.MethodsThe article describes the cases of 31 patients who were evaluated using the Wechsler Adult Intelligence Scale-Revised and the Wechsler Memory Scale-Revised prior to, and one year after, surgery.Key findingsPatients showed increases in their mean Full Scale, Verbal and Performance IQ scores of 4, 3 and 4 IQ points respectively (p < .05). 5 (17.2%), 4 (13.8%) and 4 (13.3%) patients improved in their Full-scale, Verbal and Performance IQ respectively. No significant changes were found in memory performance – with a mean increase of 1, 3 and 0 MQ points in Global, Verbal and Visual memory respectively (p < .05). Global memory improved in 3 (10.3%) patients, verbal memory in 1 (3.4%) and 1 patient (3.3%) showed deterioration in visual memory.SignificanceOur results provide evidence for unchanged memory in patients with MTLE after the procedure. No verbal memory deterioration was detected in any of our patients, while improvements were found in intellectual performance. The results suggest that stereotactic radiofrequency amygdalahippocampectomy could be superior to open surgery in terms of its neurocognitive outcomes. A larger randomised trial of these approaches is justified.     

Cognitive functions in children exposed to antiepileptic drugs in utero - Study in Georgia

ObjectiveThe cognitive teratogenicity of antiepileptic drugs (AEDs) has gained increasing attention in the last decade. The objective of the current study was to assess the effects of AED fetal exposure on the cognitive development of children of mothers with epilepsy from Georgia in a controlled study taking into consideration major confounding factors.MethodsA prospective cohort group was formed from children and mothers registered in the Georgian National AED-Pregnancy Registry. The study group's age- and gender-matched control children without fetal AED exposure were selected retrospectively. The Intelligence Quotient (IQ) using the Wechsler Adult Intelligence Scale – revised (WAIS-R) was assessed in mothers. The Wechsler Preschool and Primary Scale of Intelligence (WPPSI-4) were used to assess intellectual functioning for children of both study and control groups. Linear regression analysis was performed to detect association of AED exposure on the cognitive performance of children.ResultsIn total, 100 children aged 36 to 72 months were evaluated. The IQ of WWE was significantly lower compared to women without epilepsy in all modalities. Exposure to valproate (VPA) (n = 18) was associated with lowest cognitive performance regarding Full Scale IQ (FSIQ) (β, − 12.04; p = 0.006) and verbal comprehension (VCI) (β, − 8.89; p = 0.019). Maternal FSIQ, maternal performance IQ (PIQ), and child's age at first phrases were independent factors associated with the cognitive development of children.ConclusionsMultivariate analysis showed VPA to be an independent predictor for decreased cognitive performance. Maternal FSIQ, PIQ, and child developmental achievements were significant confounders for cognitive performance in children.     

Long-term seizure and psychosocial outcomes after resective surgery for intractable epilepsy

Resective surgery is considered an effective treatment for refractory localization-related epilepsy. Most studies have reported seizure and psychosocial outcomes of 2–5 years postsurgery and a few up to 10 years. Our study aimed to assess long-term (up to 15 years) postsurgical seizure and psychosocial outcomes at our epilepsy center. The Henry Ford Health System Corporate Data Store was accessed to identify patients who had undergone surgical resection for localization-related epilepsy from 1993 to 2011. Demographics including age at epilepsy onset and surgery, seizure frequency before surgery, and pathology were gathered from electronic medical records. Phone surveys were conducted from May 2012 to January 2013 to determine patients' current seizure frequency and psychosocial metrics including driving and employment status and use of antidepressants. Surgical outcomes were based on Engel's classification (classes I and II = favorable outcomes). McNemar's tests, chi-square tests, two sample t-tests, and Wilcoxon two sample tests were used to analyze the relationships of psychosocial and surgical outcomes with demographic and surgical characteristics. A total of 470 patients had resective epilepsy surgery, and of those, 50 (11%) had died since surgery. Of the remaining, 253 (60%) were contacted with mean follow-up of 10.6 ± 5.0 years (27% of patients had follow-up of 15 years or longer). Of the patients surveyed, 32% were seizure-free and 75% had a favorable outcome (classes I and II). Favorable outcomes had significant associations with temporal resection (78% temporal vs 58% extratemporal, p = 0.01) and when surgery was performed after scalp EEG only (85% vs 65%, p < 0.001). Most importantly, favorable and seizure-free outcome rates remained stable after surgery over long-term follow-up [i.e., < 5 years (77%, 41%), 5–10 years (67%, 29%), 10–15 years (78%, 38%), and > 15 years (78%, 26%)]. Compared to before surgery, patients at the time of the survey were more likely to be driving (51% vs 35%, p < 0.001) and using antidepressants (30% vs 22%, p = 0.013) but less likely to be working full-time (23% vs 42%, p < 0.001). A large majority of patients (92%) considered epilepsy surgery worthwhile regardless of the resection site, and this was associated with favorable outcomes (favorable = 98% vs unfavorable = 74%, p < 0.001). The findings suggest that resective epilepsy surgery yields favorable long-term postoperative seizure and psychosocial outcomes.     

Postsurgical outcome in patients with auditory auras and drug-resistant epilepsy

PurposeWe assessed whether patients with auditory auras have similar outcomes after epilepsy surgery as patients without auditory auras, and hypothesized that patients with non-dominant hemisphere foci might fare better after temporal lobe surgery than patients with dominant resections.MethodsIn this retrospective study, outcome after temporal resection was assessed for patients with drug-resistant epilepsy. Preoperative demographic data, clinical data, and surgical outcome were prospectively registered in a database from 1986 through 2016. Seizure outcome was classified as either seizure-free or relapsed.ResultsData were available in 1186 patients. Forty five patients (3.8%) reported auditory auras; 42 patients (93%) had temporal lobe epilepsy (TLE), and three patients (7%) had extratemporal epilepsy. Since most patients with auditory auras had TLE and in order to have comparable groups, we selected 41 patients with auditory auras and compared them with patients without auditory auras who had temporal lobe resections (767 patients). There were no significant demographic or clinical differences between TLE patients with auditory auras and those without. Patients who had auditory auras were more likely to relapse after temporal lobe surgery than those without (p = 0.03). Among patients who had auditory auras and temporal lobe surgery, side of surgery was not related to postoperative outcome (p = 0.3).ConclusionAuditory auras are rare among patients with drug-resistant TLE. The presence of an auditory aura in a patient with drug-resistant TLE carries a worse prognosis for a postoperative seizure free outcome and this is not related to the side of surgery.     

Two years after epilepsy surgery in children: Recognition of emotions expressed by faces

ObjectivesThe purpose of this study was to determine whether children with epilepsy surgery in their history are able to recognize emotions expressed by faces and whether this recognition is associated with demographic variables [age, sex, and verbal intelligence (VIQ)] and/or epilepsy variables (epilepsy duration, side of the surgery, surgery area, resection of the amygdala, etiology, antiepileptic drug use, and seizure freedom).MethodsTwo years after epilepsy surgery, the Facial Expression of Emotion: Stimuli and Tests (FEEST) was administered to 41 patients (age: 4–20 years, mean: 13.5 years, 24 girls) and 82 age- and sex-matched healthy controls. Data obtained longitudinally (before surgery and 6, 12, and 24 months after surgery) in a small subset (11 patients and 22 matched controls) were explored to obtain clues about the course of REEF from before surgery.ResultsCorrected for VIQ, REEF scored significantly lower in the 41 surgically treated patients than in matched control children. No significant relationship was found between REEF and any epilepsy variable. Only age at assessment predicted REEF score in both patients and controls.The longitudinal data revealed a ‘dip’ in emotion recognition at the first postsurgical assessment in the six younger patients (age: < 12.1 years). The older patients (age: 13–17 years) showed a continuous increase in REEF scores that was similar to that in controls. Two years after surgery, REEF of the younger patients recovered to, but did not exceed, the presurgical level.ConclusionNeither poor REEF present two years after childhood epilepsy surgery, nor the aberrant course of REEF in younger patients (age: < 12.1 years) was explained by epilepsy variables or poor verbal intelligence. Disentangling the mechanism of the abnormality is urgently needed, as recognizing emotional expressions is a key component in the development of more complex social perception skills.     

Interictal epileptic discharge correlates with global and frontal cognitive dysfunction in temporal lobe epilepsy

ObjectiveTemporal lobe epilepsy (TLE) with hippocampal sclerosis has widespread effects on structural and functional connectivity and often entails cognitive dysfunction. EEG is mandatory to disentangle interactions in epileptic and physiological networks which underlie these cognitive comorbidities. Here, we examined how interictal epileptic discharges (IEDs) affect cognitive performance.MethodsThirty-four patients (right TLE = 17, left TLE = 17) were examined with 24-hour video-EEG and a battery of neuropsychological tests to measure intelligence quotient and separate frontal and temporal lobe functions. Hippocampal segmentation of high-resolution T1-weighted imaging was performed with FreeSurfer. Partial correlations were used to compare the number and distribution of clinical interictal spikes and sharp waves with data from imagery and psychological tests.ResultsThe number of IEDs was negatively correlated with executive functions, including verbal fluency and intelligence quotient (IQ). Interictal epileptic discharge affected cognitive function in patients with left and right TLE differentially, with verbal fluency strongly related to temporofrontal spiking. In contrast, IEDs had no clear effects on memory functions after corrections with partial correlations for age, age at disease onset, disease duration, and hippocampal volume.ConclusionIn patients with TLE of long duration, IED occurrence was strongly related to cognitive deficits, most pronounced for frontal lobe function. These data suggest that IEDs reflect dysfunctional brain circuitry and may serve as an independent biomarker for cognitive comorbidity.     

Cognitive outcome after epilepsy surgery in children: A controlled longitudinal study

ObjectiveTo analyze the determinants of cognitive outcome two years after surgery for drug-resistant epilepsy in a cohort of 31 children when compared to a control group of 14 surgical candidates who had yet to undergo surgery two years after the first neuropsychological assessment.MethodsControlled longitudinal study including three evaluations of IQ (Intelligence Quotient) scores or GDQ (General Developmental Quotient) for each group depending on the patient's age: prior to surgery (T0), one year (T1) and two years (T2) after surgery for the surgical group; baseline (T0) and one year (T1) and 2 years (T2) after the first evaluation for the control-group. At follow-up, 25 children (80%) of the surgical group were seizure free, while seizure outcome was unsatisfactory in the remaining six (20%).To analyze language, visuomotor skills, memory, reading, visual attention, and behavior, we selected 11 school age children in the surgical group and nine controls. We reported performance prior to (T0) and one year after surgery (T1).ResultsThere was a significant correlation between earlier age at seizure onset and lower IQ/GDQ at T0 (r = 0.39; p = 0.03) in the overall cohort. IQ/GDQ scores did not significantly differ between the surgical and control groups when analyzed at T0 and T2. However, they evolved differently with an improved developmental trajectory becoming identifiable only in the surgical group (F_1,31 = 5.33 p = 0.028; η² = 0.15). There was also a significant increase of forward digit span (Z = 2.33; p = 0.02) and Rey recall scores (Z = 1.97; p = 0.049) in the surgical school age subgroup at T1 versus T0.SignificanceWe identified significantly different developmental trajectories in operated versus non- operated children with improved IQ/GDQ scores in operated children only. We also observed a significant increase of digit span scores and Rey recall scores a year after surgery. Further studies including larger samples with longer follow-ups are needed to confirm these preliminary findings.     

Long-term outcomes of epilepsy surgery in tuberous sclerosis complex

Approximately 50% of patients with tuberous sclerosis complex (TSC) present intractable epilepsy, and surgery is an option for those patients. Hereby, we analyze long-term seizure control and neuropsychological outcomes of epilepsy surgery in patients with TSC. Clinical data were retrospectively collected from 66 patients with TSC and epilepsy followed up over 5 years, 51 of whom underwent epilepsy surgery between 2001 and 2011. Reductions in the number of seizures were analyzed at 1-year (1FU), 5-year (5FU), and 10-year (10FU) follow-ups visits after the operation. Influential factors on postoperative seizure free and intelligence quotient (IQ) and quality-of-life (QOL) outcomes were evaluated at 5FU. Resective procedures included 26 tuber resections, 15 lobectomies, and 10 tuber resections and lobectomies. Corpus callosotomies were performed as the adjunctive approach in 11 cases with low IQ. The percentages of seizure-free cases were 74.5% at 1FU, 58.8% at 5FU, and 47.8% at 10FU, and the predictive factor for long-term postoperative seizure freedom was the history of preoperative seizures and preoperative full-scale IQ. Significant improvements were found in performance IQ, full-scale IQ, and QOL in patients from the surgery group, particularly those who were seizure free after the operation. Our study showed that epilepsy surgery in TSC with epilepsy rendered improvements in seizure control, full-scale IQ, and QOL. Satisfactory long-term seizure control was often achieved with an early operation and without mental retardation, and improvements in QOL and IQ were frequently observed in postoperative patients who remained seizure free.     

The impact of stereotactic laser ablation at a typical epilepsy center

PurposeStereotactic laser ablation (SLA) is a novel form of epilepsy surgery for patients with drug-resistant focal epilepsy. We evaluated one hundred consecutive surgeries performed for patients with epilepsy to address the impact of SLA on our therapeutic approach, as well as patient outcomes.MethodsA retrospective, single center analysis of the last one hundred neurosurgeries for epilepsy was performed from 2013 to 2015. Demographics, surgical procedures, and postoperative measures were assessed up to 5 years to compare the effect of SLA on outcome. Confidence intervals (CI) and comparative tests of proportions compared outcomes for SLA and resective surgery. Procedural categorical comparison used Chi-square and Kaplan–Meier curves. Student t-test was utilized for single variables such as age at procedure and seizure onset.ResultsOne hundred surgeries for epilepsy yielded thirty-three SLAs and twenty-one resections with a mean of 21.7-month and 21.3-month follow-up, respectively. The temporal lobe was the most common target for SLA (92.6%) and resection (75%). A discrete lesion was present on brain magnetic resonance imaging (MRI) in 27/32 (84.4%) of SLA patients compared with 7/20 (35%) of resection patients with a normal MRI. Overall, 55–60% of patients became seizure-free (SF). Four of five patients with initial failure to SLA became SF with subsequent resection surgery. Complications were more frequent with resection although SF outcomes did not differ (Chi square; p = 0.79). Stereotactic laser ablation patients were older than those with resections (47.0 years vs. 35.4 years, p = 0.001). The mean length of hospitalization prior to discharge was shorter for SLA (1.18 days) compared with open resection (3.43 days; SD: 3.16 days) (p = 0.0002).ConclusionWe now use SLA as a first line therapy at our center in patients with lesional temporal lobe epilepsy (TLE) before resection. Seizure-free outcome with SLA and resection was similar but with a shorter length of stay. Long-term follow-up is recommended to determine sustained SF status from SLA.