The dos and don'ts of neuropsychological assessment in epilepsy

Neuropsychological Rehabilitation for Epilepsy in India: Looking Beyond the Basics

BACKGROUND

Neuropsychological Rehabilitation (NR) helps manage cognitive deficits in epilepsy. As internationally developed programs have limited applicability to resource-limited countries, we developed a program to bridge this gap. This 6-week caregiver-assisted, culturally suitable program has components of (1) psychoeducation, (2) compensatory training, and, (3) cognitive retraining and is called EMPOWER (Indigenized Home Based Attention and Memory Rehabilitation Program for Adult Patients with Drug Refractory Epilepsy). Its efficacy needs to be determined.

METHODS

We carried out an open-label parallel randomized controlled trial. Adults aged 18-45 years with Drug Refractory Epilepsy (DRE), fluency in Hindi and or English, with impaired attention or memory (n = 28) were randomized to Intervention Group (IG) and Control Group (CG). The primary outcomes were objective memory (Auditory Verbal Learning Test), patient and caregiver reported everyday memory difficulties (Everyday Memory Questionnaire-Revised), number of memory aids in use, depression (Hamilton Depression Rating Scale), anxiety (Hamilton Anxiety Rating Scale) and quality of life (Quality of Life in Epilepsy-31). Intention to treat was carried out for group analysis. In the absence of norms necessary for computing Reliable Change Indices (RCIs), a cut-off of +1.0 Standard Deviation (SD) was utilized to identify clinically meaningful changes in the individual analysis of objective memory. A cut-off of 11.8 points was used for quality of life. Feedback and program evaluation responses were noted.

RESULTS

The majority of the sample comprised DRE patients with temporal lobe epilepsy who had undergone epilepsy surgery. Group analysis indicated improved learning (p = 0.013), immediate recall (p = 0.001), delayed recall (p < 0.001), long-term retention (p = 0.031), patient-reported everyday memory (p < 0.001), caregiver-reported everyday memory (p < 0.001), anxiety (p = 0.039) and total quality of life (p < 0.001). Individual analysis showed improvement in 50 %, 64 %, 71 %, 57 %, and 64 % of patients on learning, immediate recall, delayed recall, long-term retention, and total quality of life respectively. Despite improvements, themes indicative of a lack of awareness and understanding of cognitive deficits were identified. Overall, the program was rated favorably by patients and caregivers alike.

CONCLUSION

NR shows promise for patients with DRE, however larger studies are warranted. The role of cognition in epilepsy needs to be introduced at the time of diagnosis to help lay the foundation for education and acceptance.

Applicability of Compensatory Cognitive Training in Epilepsy to Low Resource and Literacy Settings: A Focused Review

Epilepsy is one of the most prevalent neurological disorders, accounting for over 13 million disability-adjusted life years (DALYs). Nearly 80% of people with epilepsy live in low- and middle-income countries (WHO, 2019). Rehabilitation of cognitive impairments through compensatory training in such patients encompasses a wide range of techniques. However, interventional studies exploring their efficacy remain scarce despite being recommended in various reviews. Further, cultural contexts and other related factors have often been overlooked. We aimed to appraise the existing evidence on internal and external compensatory strategies in patients with epilepsy and identify the gaps and pitfalls in the existing literature for applicability to low resource and literacy settings from a neuropsychological perspective.

Memory Rehabilitation in Patients with Epilepsy: a Systematic Review

Memory failure is a common clinical concern of patients with epilepsy and is associated with significant functional impairments. Thus, memory rehabilitation is of critical clinical importance. In this article, we aimed to systematically evaluate the efficacy of memory rehabilitation in patients with epilepsy. The Preferred Items for Systematic Reviews and Meta-Analyses (PRISMA) was used to guide searches, extraction and reporting of data in this review. PsycINFO, Medline and PsychBITE searches yielded 95 studies. Twelve papers met inclusion criteria, reporting outcomes of cognitive or behavioural interventions that specifically targeted the rehabilitation of memory in patients with epilepsy. Methodological rigour was rated using the Single-Case Experimental Design (SCED) scale for single-case studies and a modified version of the Downs and Black checklist for group studies. Twelve prospective studies, nine group (six pre-post design, one waitlist crossover, two randomised controlled trials) and three single-case studies were identified. Eleven of the studies included adults, eight of which involved adults with temporal lobe epilepsy (TLE). One paediatric study was identified. The quality of group studies ranged from 36% (poor) to 72% (good), using the modified Downs and Black checklist. Single-case studies were assessed using the SCED scale and assessed to range in quality from four to seven out to 11. Overall, memory rehabilitation was associated with improved memory function in all studies. Verbal memory outcomes were most commonly examined and associated with improvements. This review found that the level of evidence available to support rehabilitation of memory in patients with epilepsy was generally weak and inconsistent. Nevertheless, studies conducted to date, albeit of limited methodological quality, offer preliminary evidence that memory rehabilitation is associated with improvements in verbal memory in patients with temporal lobe epilepsy. Little is known about the efficacy of memory rehabilitation in patients with non-TLE, children, and other aspects of memory difficulties. Guidelines for future research are proposed.

Beating the Odds: Intact Neuropsychological Functioning despite TLE

Patients with Temporal lobe epilepsy (TLE) frequently display cognitive comorbidity and can have widespread network abnormalities, which might affect a variety of cognitive and intellectual functions. As a result, refractory TLE seems to be associated with slow but ongoing cognitive deterioration. The case is of a 32 year old, right handed male, engineering graduate, diagnosed with TLE- right mesial, 12 years ago. A number of head injuries were caused due to the seizure present, which includes a fall from height of 12 feet in childhood. The neuropsychological tests administered were Gesell’s Drawing Test, Mini Mental State Examination, PGI Memory Scale, Battery of Performance Tests of Intelligence, Verbal Adult Intelligence Scale, Hamilton Rating Scale for Depression, Bender Visual Motor Gestalt Test and Dysfunction Analysis Questionnaire. No impairment found on orientation; average cognitive functioning; above average attention and concentration, verbal working memory, visual and verbal memory; average practical ability, abstract ability, average verbal intellectual ability; superior ability on comprehension and average performance ability. Mild to moderate impairment on perceptuo-motor functioning and an evidence of depression were present. Patient showed high dysfunction in personal, social, vocational and cognitive areas. The study highlights that even despite chronic epilepsy, with a series of head injuries due to the seizures; an individual can still have average neuropsychological abilities. Holistic neuropsychological rehabilitation along with Vocational Retraining would go a long way in the functional independence of the patient. Neuropsychologists have a significant role in the assessment, treatment, and rehabilitation of people with epilepsy.

Clinical utility of the Wechsler Memory Scale--Fourth Edition (WMS-IV) in predicting laterality of temporal lobe epilepsy among surgical candidates

This study evaluated the accuracy of the Wechsler Memory Scale--Fourth Edition (WMS-IV) in identifying functional cognitive deficits associated with seizure laterality in localization-related temporal lobe epilepsy (TLE) relative to a previously established measure, the Rey Auditory Verbal Learning Test (RAVLT). Emerging WMS-IV studies have highlighted psychometric improvements that may enhance its ability to identify lateralized memory deficits. Data from 57 patients with video-EEG-confirmed unilateral TLE who were administered the WMS-IV and RAVLT as part of a comprehensive presurgical neuropsychological evaluation for temporal resection were retrospectively reviewed. We examined the predictive accuracy of the WMS-IV not only in terms of verbal versus visual composite scores but also using individual subtests. A series of hierarchal logistic regression models were developed, including the RAVLT, WMS-IV delayed subtests (Logical Memory, Verbal Paired Associates, Designs, Visual Reproduction), and a WMS-IV verbal-visual memory difference score. Analyses showed that the RAVLT significantly predicted laterality with overall classification rates of 69.6% to 70.2%, whereas neither the individual WMS-IV subtests nor the verbal-visual memory difference score accounted for additional significant variance. Similar to previous versions of the WMS, findings cast doubt as to whether the WMS-IV offers significant incremental validity in discriminating seizure laterality in TLE beyond what can be obtained from the RAVLT.

Visuo-spatial memory tests in right temporal lobe epilepsy foci: clinical validity

OBJECTIVE

To examine the appropriateness of visual memory tests as an identification method for right mesial temporal lobe dysfunctions in an epilepsy patient group and to study the relationship and possible overlap with non-memory cognitive domains and demographic variables.

METHODS

Eighty preoperative candidates with mesial temporal lobe epilepsy (TLE) were examined using the "Corsi Block-Tapping Test", "Diagnosticum für Cerebralschädigung" (DCS), the path subtest of the "Verbaler und Visueller Merkfähigkeitstest" (VVM), and the Rey-Osterrieth Complex Figure Test (ROCF). Factorial analyses were performed on raw scores to determine the effect of epilepsy-related variables, interictal epileptiform discharges (IEDs) and presence of cortical dysgenesis, on visual and verbal memory parameters. Sensitivity, specificity and Receiver Operating Characteristic (ROC) curves were calculated based on normative data. Furthermore, Spearman correlations between memory and non-memory cognitive tasks were performed.

RESULTS

The scores for test sensitivity and specificity and the ROC curves illustrate the tests' poor capacity to lateralize the functional deficit zone even when epilepsy-related factors, such as cortical dysgenesis or presence of contralateral IEDs were controlled. Significant correlations were found between the visual memory measures and nonverbal reasoning, processing speed, attentional flexibility, and visual planning.

CONCLUSION

These neuropsychological tests are not sensitive enough to lateralize the epileptogenic focus in temporal lobe epilepsy patients since in addition to learning and consolidation processes, they measure additional cognitive domains. These results have implications for clinical neuropsychologists, in terms of test choice and the interpretation in the context of presurgical diagnostics.

The contribution of neuropsychology to diagnostic assessment in epilepsy

Neuropsychology plays a vital role in the treatment of epilepsy, providing information on the effects of seizures on higher cortical functions through the measurement of behavioral abilities and disabilities. This is accomplished through the design, administration and interpretation of neuropsychological tests, including those used in functional neuroimaging or cortical mapping and in intracarotid anesthetic procedures. The objective of this paper is to define and summarize in some detail the role and methods of neuropsychologists in specialized epilepsy centers. Included are information and recommendations regarding basic ingredients of a thorough neuropsychological assessment in the epilepsy setting, as well as suggestions for an abbreviated alternative exam when needed, with emphasis on functions associated with specific brain regions. The paper is intended for novice and experienced neuropsychologists to enable them to develop or evaluate their current practices, and also for other clinicians, who seek a better understanding of the methodology underlying the neuropsychological input to their work.

The cognitive and psychomotor effects of remacemide and carbamazepine in newly diagnosed epilepsy

An international trial comparing remacemide hydrochloride with carbamazepine was undertaken in individuals with newly diagnosed epilepsy using a novel double-blind, parallel-group, double triangular sequential design. Patients with two or more partial or generalized tonic-clonic seizures in the previous year were randomized to remacemide or carbamazepine and titrated to a target dose of 600 mg/day. Subsequent dosage adjustments were allowed while maintaining the blind. Repeated assessments of neuropsychological function and mood were carried out using computerized and conventional measures. The trial was completed 20 months after initiation, following the second interim analysis. Efficacy as measured by seizure recurrence showed remacemide to be inferior to carbamazepine. Baseline cognitive and neuropsychological measures showed impairment across the whole patient population. Cognitive/neuropsychological performance at 8, 24, and 48 weeks was compared with that at baseline. Significant deterioration was seen on measures of information processing speed and attention after treatment with carbamazepine. The study data provide evidence for the utility and sensitivity of a number of cognitive assessments, which may be employed in future trials of antiepileptic drugs.