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Journal Article•DOI•

Neuropsychological outcomes after epilepsy surgery: systematic review and pooled estimates.

Elisabeth M. S. Sherman1, Samuel Wiebe1, Samuel Wiebe2, Taryn B. Fay-McClymont3, Jose F. Tellez-Zenteno4, Amy Metcalfe1, Lisbeth Hernandez-Ronquillo4, Walter Hader2, Walter Hader1, Walter Hader3, Nathalie Jette2, Nathalie Jette1 •
University of Calgary1, Foothills Medical Centre2, Alberta Children's Hospital3, University of Saskatchewan4
01 May 2011-Epilepsia (Centre for Reviews and Dissemination (UK))-Vol. 52, Iss: 5, pp 857-869
TL;DR: A systematic review was conducted to derive pooled estimates of the rate of losses and gains in neuropsychological functions after epilepsy surgery, using empirically based methods for quantifying cognitive change.
Abstract: Summary Purpose: Epilepsy surgery is a safe surgical procedure, but it may be associated with cognitive changes. Estimates of the risk of decline in specific neuropsychological domains after epilepsy surgery would assist surgical decision making in clinical practice. The goal of this study was to conduct a systematic review to derive pooled estimates of the rate of losses and gains in neuropsychological functions after epilepsy surgery, using empirically based methods for quantifying cognitive change. Methods: An extensive literature search using PubMed, EmBase, and the Cochrane database was conducted, yielding 5,061 articles on epilepsy surgery, with 193 on neuropsychological outcomes (IQ, memory, language, executive functioning, attention, and subjective cognitive changes). Key Findings: Of these, 23 met final eligibility criteria, with 22 studies involving temporal surgery only. Key aspects of inclusion criteria were N ≥ 20 and use of reliable change index or standardized regression-based change estimates. In addition to the proportion of patients experiencing losses and gains in each individual test, a single pooled estimate of gains and losses for each cognitive domain was derived using a random effects model. Weighted estimates indicated a risk to verbal memory with left-sided temporal surgery of 44%, twice as high as the rate for right-sided surgery (20%). Naming was reduced in 34% of left-sided temporal patients, with almost no patients with gains (4%). Pooled data on IQ, executive functioning, and attention indicated few patients show declines post surgery, but a substantial rate of improvement in verbal fluency with left-sided temporal surgery (27%) was found. Self-reported cognitive declines after epilepsy surgery were uncommon, and gains were reported in some domains where losses were found on objective tests (i.e., verbal memory and language). Variations in surgical techniques did not appear to have a large effect on cognitive outcomes, except for naming outcomes, which appeared better with more conservative resections. Sensitivity to postoperative changes differed across visual memory tests, but not verbal memory tests. Few conclusions could be made regarding cognitive risks and benefits of extratemporal epilepsy surgery, or of epilepsy surgery in children. Significance: In sum, epilepsy surgery is associated with specific cognitive changes, but may also improve cognition in some patients. The results provide base rate estimates of expected cognitive gains and losses associated with epilepsy surgery that may prove useful in clinical settings.
Citations
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Journal Article•DOI•
Early Surgical Therapy for Drug-Resistant Temporal Lobe Epilepsy: A Randomized Trial

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Jerome Engel1, Michael P. McDermott, Samuel Wiebe, John T. Langfitt, John M. Stern, Sandra Dewar, Michael R. Sperling, Irenita Gardiner, Giuseppe Erba, Itzhak Fried, Margaret Jacobs, Harry V. Vinters, Scott Mintzer, Karl Kieburtz •
University of California, Los Angeles1
07 Mar 2012-JAMA
TL;DR: Whether surgery soon after failure of 2 antiepileptic drug (AED) trials is superior to continued medical management in controlling seizures and improving quality of life (QOL) is sought and among patients with newly intractable disabling MTLE, resective surgery plus AED treatment resulted in a lower probability of seizures during year 2 of follow-up than continued AEDtreatment alone.
Abstract: Context Despite reported success, surgery for pharmacoresistant seizures is often seen as a last resort. Patients are typically referred for surgery after 20 years of seizures, often too late to avoid significant disability and premature death. Objective We sought to determine whether surgery soon after failure of 2 antiepileptic drug (AED) trials is superior to continued medical management in controlling seizures and improving quality of life (QOL). Design, Setting, and Participants The Early Randomized Surgical Epilepsy Trial (ERSET) is a multicenter, controlled, parallel-group clinical trial performed at 16 US epilepsy surgery centers. The 38 participants (18 men and 20 women; aged ≥12 years) had mesial temporal lobe epilepsy (MTLE) and disabling seizues for no more than 2 consecutive years following adequate trials of 2 brand-name AEDs. Eligibility for anteromesial temporal resection (AMTR) was based on a standardized presurgical evaluation protocol. Participants were randomized to continued AED treatment or AMTR 2003-2007, and observed for 2 years. Planned enrollment was 200, but the trial was halted prematurely due to slow accrual. Intervention Receipt of continued AED treatment (n = 23) or a standardized AMTR plus AED treatment (n = 15). In the medical group, 7 participants underwent AMTR prior to the end of follow-up and 1 participant in the surgical group never received surgery. Main Outcome Measures The primary outcome variable was freedom from disabling seizures during year 2 of follow-up. Secondary outcome variables were health-related QOL (measured primarily by the 2-year change in the Quality of Life in Epilepsy 89 [QOLIE-89] overall T-score), cognitive function, and social adaptation. Results Zero of 23 participants in the medical group and 11 of 15 in the surgical group were seizure free during year 2 of follow-up (odds ratio = ∞; 95% CI, 11.8 to ∞; P Conclusions Among patients with newly intractable disabling MTLE, resective surgery plus AED treatment resulted in a lower probability of seizures during year 2 of follow-up than continued AED treatment alone. Given the premature termination of the trial, the results should be interpreted with appropriate caution. Trial Registration clinicaltrials.gov Identifier: NCT00040326

902 citations

Journal Article•DOI•
Resective Epilepsy Surgery for Drug-Resistant Focal Epilepsy: A Review

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Barbara C. Jobst1, Gregory D. Cascino2•
Dartmouth–Hitchcock Medical Center1, Mayo Clinic2
20 Jan 2015-JAMA
TL;DR: Epilepsy surgery was less effective when there were extratemporal lesions, the epilepsy was not associated with a structural lesion, or both, and quality of life improved after surgery but improved the most in patients who were seizure-free after surgery.
Abstract: Importance Epilepsy surgery is indicated for patients with focal seizures who do not respond to appropriate antiepileptic drug therapy consisting of 2 or more medications. Objectives To review resective surgery outcomes for focal epilepsy, to identify which patients benefit the most, and to discuss why epilepsy surgery may not be universally accepted. Evidence Review Medline and Cochrane databases were searched between January 1993 and June 2014 for randomized clinical trials, meta-analyses, systematic reviews, and large retrospective case series (>300 patients) using Medical Subject Headings and indexed text terms. Fifty-five articles were included. Subpopulations and prognostic factors were identified. Systematic reviews for cognitive, psychiatric, quality-of-life, and psychosocial outcomes were included. Findings Two randomized clinical trials enrolling 118 patients with temporal lobe epilepsy found greater freedom from seizures with surgery when compared with continued medical treatment (58% vs 8% [n = 80] and 73% vs 0% [n = 38], P Conclusions and Relevance Epilepsy surgery reduced seizure activity in randomized clinical trials when compared with continued medical therapy. Long-term cognitive, psychiatric, psychosocial, and quality-of-life outcomes were less well defined. Despite good outcomes from high-quality clinical trials, referrals of patients with seizures refractory to medical treatment remain infrequent.

478 citations

Additional excerpts

  • ...6) At 5 y: 320 (52) [48-56] At 10 y: 289 (47) [42-51]...

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Journal Article•DOI•
Epilepsy surgery in children and adults

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Philippe Ryvlin1, Philippe Ryvlin2, Philippe Ryvlin3, J. Helen Cross4, Sylvain Rheims2, Sylvain Rheims3 •
University Hospital of Lausanne1, Lyon College2, French Institute of Health and Medical Research3, UCL Institute of Child Health4
01 Nov 2014-Lancet Neurology
TL;DR: New guidelines recommend earlier and more systematic assessment of patients' eligibility for surgery than is seen at present, as evidence is scarce for the indication and effect of most presurgical investigations, with no biomarker precisely delineating the epileptogenic zone.
Abstract: Epilepsy surgery is the most effective way to control seizures in patients with drug-resistant focal epilepsy, often leading to improvements in cognition, behaviour, and quality of life. Risks of serious adverse events and deterioration of clinical status can be minimised in carefully selected patients. Accordingly, guidelines recommend earlier and more systematic assessment of patients' eligibility for surgery than is seen at present. The effectiveness of surgical treatment depends on epilepsy type, underlying pathology, and accurate localisation of the epileptogenic brain region by various clinical, neuroimaging, and neurophysiological investigations. Substantial progress has been made in the methods of presurgical assessment, particularly in patients with normal features on MRI, but evidence is scarce for the indication and effect of most presurgical investigations, with no biomarker precisely delineating the epileptogenic zone. A priority for the development of epilepsy surgery is the generation of high-level evidence to promote the harmonisation and dissemination of best practices.

324 citations

Journal Article•DOI•
Evidence-Based Indicators of Neuropsychological Change in the Individual Patient: Relevant Concepts and Methods

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Kevin Duff1•
University of Utah1
01 May 2012-Archives of Clinical Neuropsychology
TL;DR: A review of the relevant concepts and methods used in repeated neuropsychological evaluations can be found in this paper, where the focus is on the understanding and application of these concepts in the evaluation of the individual patient through examples.

297 citations

Journal Article•DOI•
Early Surgical Therapy for Drug-Resistant Temporal Lobe Epilepsy: A Randomized Trial

[...]

Jerome Engel, Michael P. McDermott, Samuel Wiebe, John T. Langfitt, John M. Stern, Sandra Dewar, Michael R. Sperling, Irenita Gardiner, Giuseppe Erba, Itzhak Fried, Margaret Jacobs, Harry V. Vinters, Scott Mintzer, Karl Kieburtz 
01 Jun 2013-Survey of Anesthesiology

226 citations

References
More filters
Journal Article•DOI•
A randomized, controlled trial of surgery for temporal-lobe epilepsy.

[...]

Samuel Wiebe1, Warren T. Blume, John P. Girvin, Michael Eliasziw•
University of Western Ontario1
02 Aug 2001-The New England Journal of Medicine
TL;DR: In temporal-lobe epilepsy, surgery is superior to prolonged medical therapy, and Randomized trials of surgery for epilepsy are feasible and appear to yield precise estimates of treatment effects.
Abstract: Background Randomized trials of surgery for epilepsy have not been conducted, because of the difficulties involved in designing and implementing feasible studies. The lack of data supporting the therapeutic usefulness of surgery precludes making strong recommendations for patients with epilepsy. We conducted a randomized, controlled trial to assess the efficacy and safety of surgery for temporal-lobe epilepsy. Methods Eighty patients with temporal-lobe epilepsy were randomly assigned to surgery (40 patients) or treatment with antiepileptic drugs for one year (40 patients). Optimal medical therapy and primary outcomes were assessed by epileptologists who were unaware of the patients' treatment assignments. The primary outcome was freedom from seizures that impair awareness of self and surroundings. Secondary outcomes were the frequency and severity of seizures, the quality of life, disability, and death. Results At one year, the cumulative proportion of patients who were free of seizures impairing awarenes...

2,923 citations

"Neuropsychological outcomes after e..." refers background in this paper

  • ...It is safe and effective (Wiebe et al., 2001), with clinically important sequelae occurring in only 2% of patients with temporal lobe epilepsy, the most commonly operated group (Wiebe, 2004)....

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Journal Article•DOI•
A Compendium of Neuropsychological Tests: Administration, Norms, and Commentary

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Ola A. Selnes
01 Nov 1991-Neurology

2,698 citations

"Neuropsychological outcomes after e..." refers background or methods in this paper

  • ...For these reasons, empirically based techniques for measuring individual change, such as the reliable change index (RCI) and standardized regression-based (SRB) change scores provide more precise and reliable risk estimates than other methods for measuring cognitive changes after epilepsy surgery, and are now the gold standard in the field (Chelune et al., 1993; Hermann et al., 1996; Sawrie et al., 1996; Dodrill et al., 2001; Strauss et al., 2006)....

    [...]

  • ...…(SRB) change scores provide more precise and reliable risk estimates than other methods for measuring cognitive changes after epilepsy surgery, and are now the gold standard in the field (Chelune et al., 1993; Hermann et al., 1996; Sawrie et al., 1996; Dodrill et al., 2001; Strauss et al., 2006)....

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Journal Article•DOI•
Chronic epilepsy and cognition

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Christian E. Elger1, Christoph Helmstaedter1, Martin Kurthen1•
University Hospital Bonn1
01 Nov 2004-Lancet Neurology
TL;DR: Cognitive recovery in the adult brain after successful surgery indicates functional compensation and, to some degree, functional reorganisation or a reactivation of functions previously suppressed by influence from distant but connected epileptogenic areas.
Abstract: Cognitive profiles in epilepsy are as heterogenous as the epileptic syndromes themselves; causes, topography of epileptogenic areas, pathogenetic mechanisms, and the diverse features characterising the clinical course all contribute to the effect on cognition. Chronic epilepsy generally impairs cognition, but it also induces processes of functional reorganisation and behavioural compensation. In most idiopathic epilepsies, cognition is only mildly deteriorated or even normal by clinical standards. Localisation-related cryptogenic and symptomatic epilepsy disorders are accompanied by focal deficits that mirror the specific functions of the respective areas. Poor cognitive outcome is generally associated with an early onset and a long duration of the disease and with poor seizure control. There is evidence that cognitive functions are already impaired at the onset of the disease, and that the maturation of cognitive functions in children is susceptible to the adverse influence of epilepsy. In adults, cognitive decline progresses very slowly over decades with an age regression similar to that of people without epilepsy. Successful epilepsy surgery can stop or partly reverse the unfavourable cognitive development, but left-temporal resections in particular have a high risk of additional postoperative verbal memory impairment. Cognitive recovery in the adult brain after successful surgery indicates functional compensation and, to some degree, functional reorganisation or a reactivation of functions previously suppressed by influence from distant but connected epileptogenic areas.

647 citations

"Neuropsychological outcomes after e..." refers background in this paper

  • ...Second, chronic epilepsy itself carries the possibility of cognitive plateauing or decline and decreased psychological, occupational, and social functioning and quality of life with continuing seizures (Helmstaedter et al., 2003; Elger et al., 2004; Sillanpaa et al., 2004)....

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Journal Article•DOI•
Chronic epilepsy and cognition: a longitudinal study in temporal lobe epilepsy.

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Christoph Helmstaedter, Martin Kurthen, Silke Lux1, Markus Reuber2, Christian E. Elger •
Forschungszentrum Jülich1, Royal Hallamshire Hospital2
01 Oct 2003-Annals of Neurology
TL;DR: Chronic temporal lobe epilepsy is associated with progressive memory impairment, and surgery, particularly if unsuccessful, accelerates this decline, however, memory decline may be stopped and even reversed if seizures are fully controlled.
Abstract: It remains unclear whether uncontrolled epilepsy causes mental decline. This longitudinal study contrasts change of memory and nonmemory functions in 147 surgically and 102 medically treated patients with temporal lobe epilepsy. All participants were evaluated at baseline (T1) and after 2 to 10 years (T3). Surgical patients underwent additional testing 1 year postoperatively (T2). Data were analyzed on an individual and group level. Sixty-three percent of the surgical and 12% of the medically treated patients were seizure-free at T3. Fifty percent of the medically treated and 60% of the surgical patients showed significant memory decline at T3 with little change in nonmemory functions (difference not significant). Surgery anticipated the decline seen in the medically treated group and exceeded it when surgery was performed on the left, or if seizures continued postoperatively. Seizure-free surgical patients showed recovery of nonmemory functions at T2 (p < 0.001) and of memory functions at T3 (T3, p = 0.03). Multiple regression indicated retest interval, seizure control, and mental reserve capacity as predictors of performance changes. In addition, psychosocial outcome was better when seizures were controlled. In conclusion, chronic temporal lobe epilepsy is associated with progressive memory impairment. Surgery, particularly if unsuccessful, accelerates this decline. However, memory decline may be stopped and even reversed if seizures are fully controlled.

607 citations

"Neuropsychological outcomes after e..." refers background in this paper

  • ...One study on sustained attention reported substantial gains for both left and right patients (28–29%) (Helmstaedter et al., 2003), with a very low rate of losses regardless of side (2–8%)....

    [...]

  • ...Second, chronic epilepsy itself carries the possibility of cognitive plateauing or decline and decreased psychological, occupational, and social functioning and quality of life with continuing seizures (Helmstaedter et al., 2003; Elger et al., 2004; Sillanpaa et al., 2004)....

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  • ...(Helmstaedter et al., 2003), with a very low rate of losses regardless of side (2–8%)....

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  • ...Objective declines in memory have important functional implications, including a higher risk of lower work or school status over the long-term (Helmstaedter et al., 2003; Baxendale & Thompson, 2005)....

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Journal Article•DOI•
Individual change after epilepsy surgery: Practice effects and base-rate information.

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Gordon J. Chelune1, Richard I. Naugle1, Hans Lüders, Jeffery Sedlak1, Issam A. Awad1 •
Cleveland Clinic1
01 Jan 1993-Neuropsychology (journal)

533 citations

"Neuropsychological outcomes after e..." refers background or methods or result in this paper

  • ...Study N Test Left surgery Right surgery % Loss % Gain % Loss % Gain Executive functioning: Word Fluency Davies et al. (1998) N = 99 Word Fluency (MAE COWA) 2 – – – Helmstaedter et al. (2003) N = 147 Word Fluency 12 16 21 8 Martin et al....

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  • ...Study N Test Left surgery Right surgery % Loss % Gain % Loss % Gain Executive functioning: Word Fluency Davies et al. (1998) N = 99 Word Fluency (MAE COWA) 2 – – – Helmstaedter et al. (2003) N = 147 Word Fluency 12 16 21 8 Martin et al. (2000) N = 174 Word Fluency (MAE COWA) 18 40 20 27 Verbal fluency weighted average (*Note: Asterisked data are statistically heterogeneous p = 0....

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  • ...For these reasons, empirically based techniques for measuring individual change, such as the reliable change index (RCI) and standardized regression-based (SRB) change scores provide more precise and reliable risk estimates than other methods for measuring cognitive changes after epilepsy surgery, and are now the gold standard in the field (Chelune et al., 1993; Hermann et al., 1996; Sawrie et al., 1996; Dodrill et al., 2001; Strauss et al., 2006)....

    [...]

  • ...The other study, using an attention paradigm that measures attentional span, working memory, and orientation, found few changes after surgery (Chelune et al., 1993)....

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  • ...…(SRB) change scores provide more precise and reliable risk estimates than other methods for measuring cognitive changes after epilepsy surgery, and are now the gold standard in the field (Chelune et al., 1993; Hermann et al., 1996; Sawrie et al., 1996; Dodrill et al., 2001; Strauss et al., 2006)....

    [...]

Related Papers (5)
A randomized, controlled trial of surgery for temporal-lobe epilepsy.

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[...]

01 Oct 2003-Annals of Neurology
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