Anna Edelvik

Long-term outcomes of epilepsy surgery in Sweden A national prospective and longitudinal study

Objective: To investigate prospective, population-based long-term outcomes concerning seizures and antiepileptic drug (AED) treatment after resective epilepsy surgery in Sweden. Methods: Ten- and 5-year follow-ups were performed in 2005 to 2007 for 278/327 patients after resective epilepsy surgery from 1995 to 1997 and 2000 to 2002, respectively. All patients had been prospectively followed in the Swedish National Epilepsy Surgery Register. Ninety-three patients, who were presurgically evaluated but not operated, served as controls. Results: In the long term (mean 7.6 years), 62% of operated adults and 50% of operated children were seizure-free, compared to 14% of nonoperated adults (p < 0.001) and 38% of nonoperated children (not significant). Forty-one percent of operated adults and 44% of operated children had sustained seizure freedom since surgery, compared to none of the controls (p < 0.0005). Multivariate analysis identified ≥30 seizures/month at baseline and long epilepsy duration as negative predictors and positive MRI to be a positive predictor of long-term seizure-free outcome. Ten years after surgery, 86% of seizure-free children and 43% of seizure-free adults had stopped AEDs in the surgery groups compared to none of the controls (p < 0.0005). Conclusions: This population-based, prospective study shows good long-term seizure outcomes after resective epilepsy surgery. The majority of the patients who are seizure-free after 5 and 10 years have sustained seizure freedom since surgery. Many patients who gain seizure freedom can successfully discontinue AEDs, more often children than adults. Classification of evidence: This study provides Class III evidence that more patients are seizure-free and have stopped AED treatment in the long term after resective epilepsy surgery than nonoperated epilepsy patients.

Complications to invasive epilepsy surgery workup with subdural and depth electrodes: a prospective population-based observational study

Objective In some patients who undergo presurgical workup for drug-resistant epilepsy invasive seizure monitoring is needed to define the seizure onset zone and delineate eloquent cortex. Such procedures carry risks for complications causing permanent morbidity and even mortality. In this study, prospective data on complications in a national population-based sample were analysed. Design Complication data from the prospective Swedish National Epilepsy Surgery Register were analysed for 271 patients in whom therapeutic surgery was preceded by invasive monitoring 1996–2010. Results Complications occurred in 13/271 patients (4.8%). Subdural grids carried the highest risk of complications (7.4%). There was no surgical mortality or permanent morbidity. Subdural haematomas were most common (n=7) followed by epidural haematomas (n=3). Valproate treatment and having a haematoma was associated with an OR of 1.53 (CI 0.38 to 6.12) compared to having a haematoma without valproate treatment. Having a complication during invasive monitoring was associated with a significant OR of 6.27 (CI 1.32 to 29.9) of also having a complication at therapeutic surgery compared to the risk of having a complication only at surgery. Conclusions In this prospective population-based epilepsy surgery series, the most common complications were haematomas, and subdural grids carried the highest risk. Close supervision and rapid interventions led to avoidance of permanent morbidity. The clinical implications of the slightly increased risk of haematomas with valproate treatment needs further investigation as does the finding of an increased risk for complications at epilepsy surgery for patients who had a complication during invasive monitoring.

Long-term follow-up after epilepsy surgery in infancy and early childhood - A prospective population based observational study

PURPOSE To describe 2-year and long-term outcomes (five or ten years) after resective epilepsy surgery in children operated before the age of four years. METHODS This prospective, population based, longitudinal study is based on data from the Swedish National Epilepsy Surgery Register 1995-2010. The following variables were analysed: seizure frequency, antiepileptic drug treatment (AED), neurological deficits, type of operation, histopathological diagnosis and perioperative complications. RESULTS During the study period 47 children under four years had resective surgery. A majority had seizure onset within the first year of life, and the median age at surgery was two years and one month. Two thirds had neurodevelopmental abnormalities. Temporal lobe resection, frontal lobe resection and hemispherotomy predominated. A majority had malformations of cortical development. There was one major perioperative complication. At the 2-year follow-up, 21/47 children (45%) were seizure free, eight of whom were off medication. At the long-term follow-up, 16/32 (50%) were seizure-free and 11 of them off medication. Another ten (31%) had ≥75% reduction in seizure frequency. Fourteen children (44%) had sustained seizure freedom from surgery to the long-term follow-up. CONCLUSION This is the first prospective, population based, longitudinal study to show that a favourable seizure outcome is achievable in a majority of infants and young children undergoing resective epilepsy surgery and that the improvements are consistent over time. Many can also stop taking AEDs. The findings emphasise the importance of early referral to epilepsy surgery evaluation in cases of medically intractable epilepsy in infants and young children.

Prospective and longitudinal long-term employment outcomes after resective epilepsy surgery

Objective: To investigate long-term employment outcomes after resective epilepsy surgery in a national population-based cohort of adults. Methods: In the Swedish National Epilepsy Surgery Register, all adults who were operated with resective epilepsy surgery from 1995 to 2010 were identified. Two-year follow-up was available for 473/496, 5-year follow-up for 220/240, 10-year follow-up for 240/278, and 15-year follow-up for 85/109 patients. Results: There were no significant changes in employment outcome over time at group level, but for those with full-time employment at baseline, 79%, 79%, 57%, and 47% of seizure-free patients were in full-time work at 2-, 5-, 10-, and 15-year follow-up, compared to patients with benefits at baseline, where 16%, 27%, 31%, and 33% of seizure-free patients worked full time at these time points (p = 0.018 at 10 years). More patients with full-time work had ability to drive, a family of their own, and higher educational status than patients in part-time work or on benefits. Univariate predictors for employment at long term were having employment preoperatively, higher education, favorable seizure outcome, male sex, and younger age at surgery. Multivariate predictors were having employment preoperatively, favorable seizure outcome, and younger age. Conclusions: The best vocational outcomes occurred in seizure-free patients who were employed or students at baseline, which may reflect a higher general psychosocial level of function. Younger age also predicted better employment outcomes and it therefore seems plausible that early referral for surgery could contribute to better vocational outcomes.

Long-term outcomes of surgical treatment for epilepsy in adults with regard to seizures, antiepileptic drug treatment and employment

PURPOSE There is Class I evidence for short-term efficacy of epilepsy surgery from two randomized controlled studies of temporal lobe resection. Long-term outcome studies are observational. The aim of this narrative review was to summarise long-term outcomes taking the study methodology into account. METHODS A PubMed search was conducted identifying articles on long-term outcomes of epilepsy surgery in adults with regard to seizures, antiepileptic drug treatment and employment. Definitions of seizure freedom were examined in order to identify the proportions of patients with sustained seizure freedom. The quality of the long-term studies was assessed. RESULTS In a number of high-quality studies 40-50% of patients had been continuously free from seizures with impairment of consciousness 10 years after resective surgery, with a higher proportion seizure-free at each annual follow-up. The proportion of seizure-free adults in whom AEDs have been withdrawn varied widely across studies, from 19-63% after around 5 years of seizure freedom. Few long-term vocational outcome studies were identified and results were inconsistent. Some investigators found no postoperative changes, others found decreased employment for patients with continuing seizures, but no change or increased employment for seizure-free patients. Having employment at baseline and postoperative seizure freedom were the strongest predictors of employment after surgery. CONCLUSIONS Long-term studies of outcomes after epilepsy surgery are by necessity observational. There is a need for more prospective longitudinal studies of both seizure and non-seizure outcomes, considering individual patient trajectories in order to obtain valid outcome data needed for counselling patients about epilepsy surgery.

Health‐related quality of life and emotional well‐being after epilepsy surgery: A prospective, controlled, long‐term follow‐up

To evaluate health‐related quality of life (HRQOL) and emotional well‐being in resective epilepsy surgery and nonoperated patients at long‐term follow‐up.

Callosotomy in children — Parental experiences reported at long-term follow-up

Callosotomy is a palliative surgery method for selected individuals with severe, drug-resistant epilepsy. The aim of this retrospective study was to explore parental experiences of the familys life situation before and long after their child had undergone callosotomy. Semistructured interviews of the parents of 12 children were analyzed using a combination of inductive and deductive qualitative content analysis. Before surgery, parents felt that they lived in a chaotic bubble with an unbearable situation; their child had severe and frequent seizures and had to be looked after constantly. Most parents were both satisfied and dissatisfied with the given support and information. However, if the child did not improve after surgery, parents often felt that the information before surgery had not been adequate. After surgery, they found a glimpse of hope. They felt that the family got a new life; the reduced seizure severity led to a better life situation for the family. The support was described as both good and poor. The family life situation was complex, and even if they were partly satisfied with the support, it was still not enough. However, the life situation was also very stressful because of remaining seizures, behavioral problems, and sometimes, adverse effects of surgery. The families lived in disappointment and difficulty and had to fight for their rights. This indicates that these families need more information and social service coordination both before and long after surgery. They need not only tools to manage the childs disabilities but also substantial help to care for the child and to receive the social support they need.

Long-Term Seizure and Antiepileptic Drug Outcomes After Epilepsy Surgery in Adults

Epilepsy surgery is an efficacious treatment for selected persons with drug-resistant focal epilepsy, rendering many seizure-free and others significantly improved. There is Class I evidence for short-term efficacy of epilepsy surgery from two randomized controlled studies of temporal lobe resection. In order for patients to make an informed decision about the treatment option of epilepsy surgery, they also need data on the probability of long-term remission or improvement. Long-term longitudinal observational studies are necessary in order to obtain valid outcome data. From a number of such studies, the proportion of patients who have been continuously free from seizures with impairment of consciousness since resective surgery seems to be 40–50 % after 10 years, while a higher proportion have been seizure-free at least a year at each time-point assessed. The best longitudinal data are in patients who have undergone temporal lobe resection and in whom the histopathology was mesial sclerosis, and in these patients the majority of relapses occur within 5 years. Whether this course is applicable to other resection types and pathologies is not clear. There is much less information on the longitudinal course in patients who have undergone other resection types and have other causes. For many resection types, the number of patients in single-center long-term follow-ups is limited and for almost all studies there is a lack of controls. Multicenter observational studies following both operated and nonoperated patients are needed in order to obtain more robust data.