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.     

Causal attributions for seizures: Relation to preoperative psychological adjustment and postoperative psychosocial function in temporal lobe epilepsy

In a sample of 65 epilepsy patients who were temporal lobectomy candidates, the links between causal attributions, learned resourcefulness, and preoperative psychosocial adjustment were explored. In addition, attributions as predictors of objective 2-year postoperative psychosocial outcomes were examined prospectively. With illness severity controlled for, attribution of seizures to stress factors and low learned resourcefulness were predictive of poor psychosocial adjustment preoperatively. Taking personal responsibility for seizure occurrence (self-blame) was associated with better psychosocial adjustment. At 2 years, patients were divided into three groups: (a) postoperative seizure-free (n = 21), (b) postoperative not seizure-free (n = 19), and (c) nonoperated controls (n = 25). Seizure-free outcome status was associated with better psychosocial outcome. Of greater interest was the predictive value of preoperative attributions. As expected, attributions involving personal responsibility were predictive of postoperative full-time employment and receipt of disability benefits. The data enhance understanding of the ways in which patients with epilepsy manage the challenges they face and enhance the psychometric prediction of psychosocial behavioral outcomes after epilepsy surgery.     

Health-related quality of life using QOLIE-31: before and after epilepsy surgery a prospective study at a tertiary care center

Background: Outcome following epilepsy surgery has traditionally been measured in terms of relief of seizures. However, changes in health-related quality of life (HRQOL) after surgery for intractable epilepsy are also important to document. There are no studies on the Indian population which assess the outcome of epilepsy surgery in terms of HRQOL. Materials and Methods: We conducted a prospective study on the patients undergoing epilepsy surgery for intractable seizures, between February 2004 and May 2006 at our center. All patients cleared for epilepsy surgery by the epilepsy surgery team were taken up for study. All patients Results: Thirty-six patients satisfying the inclusion/exclusion criteria were included in the analysis. Twenty-nine of these (Group 1) had good seizure outcome (Engel 1 and 2), while seven patients (Group 2) had poor seizure outcome (Engel 3 and 4) at six months. Overall, 77% of all study patients were completely seizure-free at follow-up. There was no baseline difference in the seven domains of QOLIE-31 between the two groups. There was very significant improvement (P value> 0.005 using paired sample T test) in all the domains of QOLIE-31 in the good outcome group after surgery. Health-related quality of life improvement was seen in all the domains in the poor outcome group also, however, it was statistically significant only for the following parameters: seizure worry, overall QOL, emotional wellbeing, energy fatigue and social functioning domains. Improvement in seizure worry, overall QOL, emotional wellbeing and social functioning was significantly more in Group 1 as compared to Group 2. Conclusion: Complete seizure-free state after surgery is associated with very significant improvement in HRQOL parameters. Several, but not all parameters of HRQOL as assessed by QOLIE-31, improved after surgery even in the poor seizure outcome group. The improvement in domains of seizure worry, overall QOL, emotional wellbeing and social functioning is significantly more in those patients in whom complete seizure-free state is achieved.     

Outcome of frontal lobe epilepsy surgery in adults

Our aim is to investigate seizure outcome and prognostic factors after pure frontal lobe epilepsy (FLE) surgery. We retrospectively studied the operative outcome in 97 consecutive adult patients who underwent resective surgery for intractable partial epilepsy between 1991 and 2005. Based on Kaplan-Meier, the probability of an Engel Class I outcome was found to be 54.6% (95% CI 44-64) at 6 months, 49.5% (95% CI 39.3-59.6) at 2 years, 47% (CI 34-59) at 5 years and 41.9% (CI 23.5-60.3) at 10 years. If the patient was seizure free at 2-year follow-up, the probability of remaining seizure free up to 10 years was 86% (95% CI 76-98). For 13.6% of the patients a running down of seizures could be shown. Factors predictive of poor long-term outcome were incomplete resection, using of subdural grids, IED in follow-up EEG, tonic seizures and an unspecific aura or a postoperative aura. Factors predictive of good long-term outcome were the presence of a well-circumscribed lesion in preoperative MRI, ipsilateral IED in preoperative EEG, surgery before age of 30 and short epilepsy duration prior to surgery. In the multivariate analysis, preoperative well-circumscribed lesion in MRI predicts seizure remission whereas persistent postoperative auras predict seizure relapse. FLE surgery should depend on restrictive patient selection to assure favorable outcome.     

Epilepsy surgery in tuberous sclerosis complex: Emphasis on surgical candidate and neuropsychology

Purpose: To discuss neuropsychological outcome and candidate of epilepsy surgery for tuberous sclerosis complex (TSC). Methods: To retrospectively analyze clinical data of 25 patients with TSC and epilepsy who underwent epilepsy surgery between 2001 and 2007. Seizure reduction was analyzed at 1‐year (1FU), 2‐year (2FU), and 5‐year (5FU) follow‐up visits after surgery, and outcomes of intelligence quotient (IQ) and quality of life (QOL) were evaluated at 2FU. Results: Resective procedures included 14 tuber resections, 9 lobectomies, and 2 tuber resections and lobectomies. Corpus callosotomies (CCTs) were performed as the adjunctive approach in eight cases with low IQ and behavioral problems. The percentages of seizure‐free cases were 72% at 1FU, 60% at 2FU, and 54.5% at 5FU, and the factors predicting seizure freedom included the course of seizures and ages of patients. Significant improvement was found in performance IQ in patients with preoperative low IQ or CCT. Significant improvement in mean QOL score was observed in all patients, especially patients with preoperative low IQ and CCT but postoperative seizure freedom. Conclusion: To be surgical candidates, patients with TSC and epilepsy should have identified epileptogenic tubers, and candidates should include patients with low IQ and multiple epileptogenic tubers. Satisfactory seizure control was often achieved with early operation, whereas improved QOL was observed frequently in postoperative seizure‐free patients. CCT could be performed as an adjunctive approach to resective operation for TSC patients with epilepsy and low IQ and render improvement of performance IQ and QOL.     

Quality of life after extratemporal epilepsy surgery: a prospective clinical study

PURPOSE: The purpose of this prospective clinical study was to assess quality of life (QOL) and impact of seizure status on QOL in patients with extratemporal epilepsy after surgery. PATIENTS AND METHODS: Twenty-three consecutive patients who had been operated due to extratemporal epilepsy were included in this study. Quality of Life Inventory in Epilepsy-10 (QOLIE-10) questionnaire was completed by all patients before 6 months and 2 years after surgery. Results obtained from short- and long-term follow-up were compared to baseline. Furthermore, patients who were seizure-free since surgery and those who had seizure were also compared in terms of outcome in QOL after surgery. RESULTS: All patients showed significantly improved QOL in both short- and long-term follow-ups compared to preoperative status regardless of seizure status (p<0.001). Seizure-free patients showed better QOL than those of patients who continued to have seizure during postoperative period. Furthermore, improved QOL was correlated with seizure status and shorter duration of epilepsy (p=0.001). CONCLUSION: Our findings showed that improved QOL is related to postoperative seizure status. However, future clinical studies including larger population of patients with extratemporal epilepsy are required to elucidate the role of other factors.     

Factors predictive of resilience and vulnerability in new-onset epilepsy

Purpose: Epilepsy has been associated with reduced quality of life (QOL), but QOL outcomes are heterogeneous. Some people are able to maintain a good QOL despite poorly controlled epilepsy and others report poor QOL despite well‐controlled epilepsy. Maintaining a good QOL in the face of adversity is embodied by the concept of resilience. We explored the factors associated with having a resilient outcome in people with epilepsy (PWE). Our definition of adversity included socioeconomic disadvantage as well as continuing seizures. Methods: We analyzed data collected as part of the Standard and New Antiepileptic Drugs (SANAD) trial. At the end of 4‐year follow‐up, patients were classified into four groups on the basis of seizure control (good/poor) and socioeconomic status (advantaged/disadvantaged). We identified individuals with resilient and vulnerable outcomes and the factors associated with having them. Key Findings: Seizure control was more important in determining QOL than material advantage, but socioeconomic status appeared to act as an additional protective or risk factor for QOL. Significant predictors of a resilient outcome were absence of depression and fewer adverse treatment effects at 4 years and good QOL at baseline. Significant predictors of a vulnerable outcome were fair/poor health perception, presence of depression, reduced sense of mastery, and more adverse treatment effects at follow‐up. Significance: Reducing the adverse effects of treatment, along with psychosocial interventions to increase self‐mastery, reduce health concerns, treat depression, and promote positive adjustment to a diagnosis will likely improve the QOL of PWE despite less favorable clinical and socioeconomic circumstances.     

Predictors of quality of life after resective extratemporal epilepsy surgery in adults in long-term follow-up

PurposeTo present long-term outcome and predictors of the health related quality of life (HRQOL) in a large group of patients operated for refractory extratemporal epilepsy.MethodsA German QOLIE-31 questionnaire and additional questions has been mailed for all adult patients operated for extratemporal epilepsy in the Bethel Epilepsy Centre, between 1992 and 2003, 87 patients were eligible for this study.ResultsSeizure freedom, intake of antiepileptic drugs (AEDs), presence of AEDs side effect medical comorbidities and driving a car were significantly correlated to HRQOL in all subscales of QOLIE-31. Gender, age at epilepsy onset, the presence of a partner, psychiatric disease, the presence of auras and tumour pathology have a correlation to QOL in some subscales.Stepwise regression for all patients revealed that seizure freedom and medical comorbidities were highly predictive for most of the subscales of QOLIE-31. Intake of anti-epileptic drugs and AED side effects had a modest effect on QOL. The need for psychiatric treatment predicted poor cognitive function scores. Epilepsy onset at an older age predicted a minimal increase in the overall health scores. An aura at the last follow-up predicted poor medication scores.Regarding the importance of the predictors, seizure freedom and medical comorbidities were the most important predictors of QOL after surgery. AED intake and side effects had an intermediate effect on QOL; however, the gender of the patient and age at epilepsy onset had a minimal effect on QOL.ConclusionsHRQOL after extratemporal epilepsy surgery has multiple determinants. Medical comorbidities should be considered a negative risk factor for QOL during preoperative and postoperative evaluation process.     

Predictive value of early EEG after epilepsy surgery.

To determine whether EEG performed within few months after epilepsy surgery is predictive of seizure outcome, 58 consecutive patients undergoing surgery for presumptive temporal lobe epilepsy (TLE) who had clinical follow-up of at least 2 years and EEG data available both pre- and postoperatively were analyzed. Patients were classified by preoperative brain magnetic resonance imaging into lesional, cryptogenic, and hippocampal sclerosis groups. Seizure outcome was classified according to Engel's outcome scale. Comparison was made between the presence of interictal epileptiform discharges (IEDs) in the postoperative EEG and seizure outcome. Patients who experienced seizures within 2 months after surgery were considered to have early recurrence. The mean follow-up period was 3 years. Sixty percent of patients achieved a class I seizure outcome. Almost all (95%) postoperative EEGs were obtained within 4 months after surgery. IEDs were present in 26% of postoperative EEGs, but were significantly less frequent in EEGs recorded after the first two postoperative months (P = 0.011). The presence of IEDs on postoperative EEGs was not predictive of seizure outcome either in the whole cohort or in any of the subgroups, regardless of whether it was performed within or after the first two postoperative months. It was also not predictive of outcome in the 44 patients (76%) who did not suffer early recurrence. The authors conclude that EEG performed a few months after epilepsy surgery is not useful as a predictor of long-term seizure outcome.     

Epilepsy surgery: How accurate are multidisciplinary teams in predicting outcome?

BackgroundSince epilepsy surgery is an elective procedure, patients need to weigh the risks of the procedure against the likely outcome if they are to make an informed decision to proceed. The aim of this study was to examine the accuracy of multidisciplinary team predictions of postoperative outcome in epilepsy surgery candidates.MethodsAn experienced multidisciplinary team provided preoperative predictions of postoperative outcome in 94 temporal lobe epilepsy patients who subsequently proceeded to surgery and were followed up one year later.ResultsTeam predictions of postoperative outcome were generally accurate for groups of patients judged to have a 30%, 40%, 50% or 60% chance of becoming seizure free. Team estimates of odds tended to regress towards the mean. Logistic regression analyses were more accurate than the team estimates in identifying patients with a very good (>70%) or very poor (<20%) chance of complete seizure freedom. Non localising scalp EEG, necessitating the need for an invasive EEG study prior to surgery was a significant predictor of poor postoperative outcome in this series.ConclusionsProbabilities based on logistic regression models may augment and improve the accuracy of clinical estimates of postoperative outcome in patients with a very good or very poor chance of being rendered seizure free by surgery, by counteracting the tendency of regression towards the mean in team decision making.     

Predicting the psychosocial outcome of epilepsy surgery: A longitudinal perspective on the ‘burden of normality’

Good seizure outcomes and good psychosocial outcomes following epilepsy surgery do not necessarily follow one from the other. This study explored the relationship between several presurgical psychosocial characteristics and postsurgical quality-of-life outcomes. The study aimed to develop the concept of ‘the burden of normality’ and identify risk factors for a poor psychosocial outcome that could be targeted with ameliorative presurgery cognitive behavioral techniques. Data were collected from 77 epilepsy surgery patients from three UK epilepsy centers and presurgery and postsurgery follow-up data were obtained from 30–34 patients, depending on the measure. Measures were self-report. Postsurgery intervals were determined by the epilepsy surgery care pathway at individual centers. Presurgery poor levels of mental health, poor social functioning, increased belief in illness chronicity, and associating epilepsy with social role limitations were all associated with poor postsurgical quality of life. Adopting an accepting coping strategy presurgery was associated with good postoperative quality of life. Regression analysis showed that a good postsurgical quality of life was positively predicted by a presurgical coping style of being able to make the best of a situation and see challenges in a positive light (i.e., positive reinterpretation and growth from the COPE scale) and negatively predicted by presurgical levels of anxiety. These data are presented as an important step in identifying psychological red flags for an adverse psychosocial outcome to epilepsy surgery, as exemplified by the concept of the ‘burden of normality’ and specifying targets for preoperative ameliorative psychological advice.     

No apparent effect of surgery for temporal lobe epilepsy on heart rate variability

BACKGROUND: Impaired cardiac autonomic function may contribute to the risk of sudden unexpected death in epilepsy (SUDEP). Clinical observations indicate that successful epilepsy surgery is associated with a reduced risk of SUDEP. However, in a previous study we found impaired cardiac control pre-surgically in patients with poor outcome of surgery, indicating an a priori lower risk in responders to epilepsy surgery. We have now examined the effect of surgery on cardiac autonomic control in the same patients. METHODS: We used 24 h EKG recordings to assess heart rate variability (HRV) by spectral analysis in 21 consecutive patients after temporal lobe epilepsy surgery. The HRV was compared with healthy controls, with pre-surgical HRV in the same patients, and analyzed in relation to seizure control 1 year after surgery. RESULTS: The patients with poor outcome after surgery had significantly lower SD of RR-intervals, total power, very low frequency power and low frequency power than matched healthy controls. The patients with favorable outcome did not differ from the controls, and the postoperative HRV was not different from HRV before surgery in any of the patient groups. CONCLUSION: We could not demonstrate any effect on HRV of temporal lobe epilepsy surgery in these patients. The observed lower HRV in the poor outcome group was present already before epilepsy surgery as previously reported. Although our results need confirmation in a larger study, the observations suggest that the increased risk of SUDEP in patients failing epilepsy surgery may be due to a common factor predisposing to surgical failure, impaired HRV as well as to an increased risk of SUDEP.     

Current challenges in the practice of epilepsy surgery

The accurate prediction of individual outcomes after epilepsy surgery represents a key challenge facing clinicians. It requires a precise understanding of surgical candidacy and the optimal timing of surgery to maximize a range of outcomes, including medical, psychosocial, cognitive, and psychiatric outcomes. We promote careful consideration of how epilepsy has affected an individual's developmental trajectory as key to constructing more differentiated profiles of postsurgical risk or resilience across multiple outcome measures. This life span approach conceives surgery as a crucial “turning point” in an individual's development from which varied outcome trajectories may follow. This helps clinicians understand the expectations patients and families bring to surgery, and emphasizes the interplay of factors that determine a patient's outcome. It also promotes comprehensive, longitudinal assessment of outcome using data analytical techniques that capture individual differences and identify subgroups with similar trajectories. An ongoing challenge facing clinicians is the development of an outcome classification system that incorporates outcomes other than seizures. We illustrate two emerging areas of research shaping how we define surgical candidacy and predict outcome: (1) using cortico-cortical evoked potentials to identify pathways of seizure propagation and cortico-cortical networks mediating cortical functions, and (2) predicting postoperative depression using a model that incorporates psychosocial and neurobiological factors. The latter research points to the importance of routine follow-up and postoperative psychosocial rehabilitation, particularly in patients deemed at “high risk” for poor outcomes so that early treatment interventions can be implemented. Significantly more research is needed to characterize those patients with poor outcomes who may require re-surgery.     

Quality of life one year after epilepsy surgery

BackgroundThe aim of surgery for medically intractable epilepsy was to achieve seizure freedom and improve overall quality of life (QOL) in patients. This investigation looked at changes in QOL one year after epilepsy surgery and the relationship of changes to mood, language, and seizure outcomes.MethodDepressive symptoms, QOL, and naming were measured in 25 patients with temporal lobe epilepsy before and one year after dominant temporal lobe resection. The Quality of Life in Epilepsy-89 (QOLIE-89), Beck Depression Inventory II (BDI-II), and Boston Naming Test (BNT) were used, respectively, and seizure outcome was reported according to the Engel classifications. Minimum clinically important differences (MCID) and reliable change indices (RCI) were used to assess the proportion of patients who achieved meaningful improvement or worsening in the respective areas of functioning, and the relationship between outcomes was evaluated. Changes on the 17 individual items of the QOLIE-89 were also assessed.ResultsOverall, there was a significant improvement in QOL, reduction in depressive symptoms, and decline in naming one year after surgery. Positive clinically important improvement in QOL was achieved in 76% of patients, meaningful reduction of depressive symptoms was achieved in 20%, and clinically important naming declines were observed in 48% of the cohort. Sixteen patients were seizure-free one year after surgery, but there was no significant correlation between changes in QOL and seizure outcome, depressive symptoms, or naming.ConclusionThe results in the reported cohort of patients showed that surgical treatment of temporal lobe epilepsy in the dominant hemisphere resulted in clinically meaningful improvement in overall QOL and declines in naming but no significant reduction of mood disturbance.     

Preoperative depressive symptoms are not predictors of postoperative seizure control in patients with mesial temporal lobe epilepsy and hippocampal sclerosis

Retrospective data analysis was performed in a sample of 45 consecutive patients who underwent epilepsy surgery for medically refractory mTLE-HS. Beck Depression Inventory (BDI) was used preoperatively to detect actual depressive symptoms and label patients into those “with depressive symptoms” or “without depressive symptoms”. Postoperative seizure outcome one, two, and three years after surgery was classified into “complete seizure freedom” versus “presence of auras and/or seizures”. Postoperative seizure outcomes were compared in patients with and without depressive symptoms, and no significant difference of postoperative seizure outcome was found. However, there was a non-significant trend for patients with preoperative depressive symptoms to experience a postoperative running down phenomenon more frequently than nondepressed patients. Depressive symptoms, identified by the BDI, do not seem to have a predictive value for postoperative seizure outcome in this highly selected patient population with mTLE-HS, but may be positive predictors for experiencing a postoperative running down phenomenon.     

Postoperative interictal spikes during sleep contralateral to the operated side is associated with unfavourable surgical outcome in patients with preoperative bitemporal spikes.

PURPOSE: To correlate the persistence of contralateral spikes during sleep after unilateral surgery with seizure outcome in a temporal lobe epilepsy (TLE) population and to test the existing hypotheses about the origin of the contralateral spikes in temporal lobe epilepsy. METHODS: In the 19 patients selected for this study unilateral temporal lobe surgery was performed. To investigate the course of bilateral interictal epileptiform discharges observed before surgery in awake or sleep over the temporal lobe contralateral to surgery, 24 h mobile 12 channel EEG recording was performed at minimum two, in average 4.6 (2-10) years after the surgery. RESULTS: The association of postoperative contralateral spikes and non-seizure free outcome was highly significant. The existence of unilateral pathology before surgery was highly predictive for good outcome and disappearance of contralateral spikes. The association between good seizure outcome, disappearance of contralateral spikes and the existence of unilateral pathology before surgery was also significant. Our data partially satisfies the expectations of both the "seizure induced" and mirror type secondary epileptogenesis hypotheses concerning origin of contralateral spikes, but were not completely congruent with either of them. CONCLUSIONS: Unfavourable surgical outcome in a temporal lobe epilepsy group with preoperative independent bilateral interictal spikes was associated with the persistence of postoperative contralateral spikes and lack of unilateral pathology. Compared with seizure outcome the presence/absence and distribution of postoperative interictal spikes in NREM sleep not entirely fit to the predictions of existing secondary epileptogenesis hypotheses.     

Factors predictive of the outcome of frontal lobe epilepsy surgery

PURPOSE: To identify factors that predict the outcome in seizure control after frontal lobe epilepsy surgery (FLES). FLES is the second most frequent type of epilepsy surgery, but the results are generally not as good as those after anterior temporal lobectomy. METHODS: Our cohort consisted of 68 consecutive patients whose first epilepsy surgery involving the frontal lobe occurred between 1987 and 1994. Clinical history and results of imaging and electroencephalographic studies were reviewed in detail. Excellent outcome was defined as being seizure free or having only nondisabling seizures at last follow up. RESULTS: Forty of the 68 patients (58.8%) had an excellent outcome; none of the patients with a history of childhood febrile seizures had an excellent outcome, whereas outcome was excellent in 63% of those without that history (p 相似文献   

Long-term seizure outcome and its predictors in patients with recurrent seizures during the first year aftertemporal lobe resective epilepsy surgery

Purpose: The existing data on the implications of the characteristics of seizures that recur during the first year following epilepsy surgery on subsequent seizure outcome are conflicting. We investigated the impact of recurrent seizures in the first postoperative year and their attributes on long‐term seizure outcome. Methods: We studied the postoperative courses of 492 patients who had completed two or more years of follow‐up after temporal lobe resective epilepsy surgery. We used Kaplan‐Meier survival curves to define long‐term seizure outcome and assessed the predictive value of recurrent seizure characteristics on the outcome by univariate and multivariate proportional hazards regression models. Key Findings: In our patients, seizure recurrences during the first postoperative year, irrespective of the attributes of recurrent seizures (such as provoked vs. unprovoked, and timing and number of recurrences), imparted fourfold to sevenfold increased hazards for continued seizures beyond the first postoperative year. Although patients with complex partial seizures with or without secondary generalized tonic–clonic seizures (CPS/GTCS) had a sixfold increased risk, those with auras alone had only a borderline risk for seizures beyond the first postoperative year. In the multivariate model, CPS/GTCS as the predominant seizure type and three or more seizure recurrences during the first postoperative year independently predicted unfavorable long‐term seizure outcome. Significance: Our study provides valuable information that is helpful in prognosticating and counseling patients, and in making rational decisions on the withdrawal of antiepileptic drugs following surgery. Our findings enhance the general understanding of the etiopathogenesis of surgical failure.     

Discontinuation of antiepileptic drugs after successful epilepsy surgery

OBJECTIVE: To evaluate the frequency and risk factors for seizure recurrence subsequent to antiepileptic drug (AED) withdrawal in patients who underwent surgical treatment for intractable partial epilepsy and were rendered seizure-free. METHODS: The outcome of discontinuation of AED medication was studied retrospectively in 210 consecutive patients who were rendered seizure-free after epilepsy surgery performed between 1989 and 1993. RESULTS: Medical therapy was reduced in 96 patients and discontinued in 84 patients. The seizure recurrence rate after complete AED withdrawal was 14% and 36% at 2 and 5 years. In contrast, only 3% and 7% of the 30 patients who did not alter AED treatment after surgery had recurrent seizures in the same time intervals. After AED discontinuation, seizures tended to recur more often in patients with normal preoperative MRI studies compared with those with focal pathology. However, this difference did not reach significance. Intraoperative electrocorticography, extent of surgical resection, postoperative EEG, and seizure-free duration after surgery were not predictive of seizure outcome after AED withdrawal. CONCLUSIONS: AED withdrawal was associated with seizure recurrence in a significant portion of patients rendered seizure-free by epilepsy surgery. Patients with a normal preoperative MRI study showed a tendency for higher seizure recurrence, whereas the duration of seizure-free postoperative AED treatment interval did not significantly influence the seizure recurrence rate. These results will prove useful in counseling patients about discontinuing AED treatment after successful epilepsy surgery.     

Seizure outcome after temporal lobectomy for temporal lobe epilepsy: a Kaplan-Meier survival analysis

OBJECTIVE: To determine seizure outcome and its predictors in patients with medically refractory temporal lobe epilepsy (TLE) after temporal lobectomy (TL). BACKGROUND: TL is the most common surgical procedure performed in adolescents and adults for the treatment of medically refractory TLE. Seizure outcome has been reported extensively during the first few postoperative years, but little is known beyond that time. METHODS: The authors analyzed seizure outcome in 79 patients who underwent TL for epilepsy at the Duke University Medical Center from 1962 through 1984. Patients with less than 2 years of follow-up and degenerative disorders were excluded. Predictors of seizure outcome were analyzed using Kaplan-Meier survival analyses. RESULTS: The mean follow-up was 14 years (range, 2.1 to 33.6 years). Using Engel's classification, 65% of patients were class I, 15% were class II, 11% were class III, and 9% were class IV. At least one postoperative seizure occurred in 55% of subjects. The majority of recurrences (86%) took place within 2 years of surgery. Later recurrences tended not to lead to medical intractability. Higher monthly preoperative seizure frequency was associated with poor seizure outcome. A seizure-free state at 2 years was found to be a better predictor of long-term outcome than the 6-, 12-, and 18-month landmarks. CONCLUSIONS: TL provides sustained, long-term benefit in patients with medically refractory TLE. Seizure-free status at 2 years from the time of surgery is predictive of long-term remission.