Elisabeth Engman

Cognitive outcome 10 years after temporal lobe epilepsy surgery: A prospective controlled study

Objective: To explore late effects of temporal lobe resection (TLR) for epilepsy on general cognitive level and memory. Methods: Fifty-one patients who had undergone TLR (23 in the speech-dominant temporal lobe [DTL] and 28 in the nondominant temporal lobe [NDTL]) were assessed preoperatively and 2 and 10 years postoperatively. Twenty-three healthy controls were assessed at baseline and at corresponding intervals. A battery of standardized tests for assessment of general cognitive level and memory was analyzed using a linear mixed model of between-subjects treatment effect and within-subject time effect. Results: The main result was cognitive stability from 2 to 10 years after TLR. The DTL group had declined in verbal memory at the 10-year follow-up compared to the NDTL group and to the controls. However, this decline was detected already 2 years postoperatively, with no further decline from 2 to 10 years. The memory decline was not related to seizure outcome or AED treatment. The NDTL group showed less improvement in performance IQ (PIQ) at the 10-year follow-up compared to the controls. The most important correlate to inferior PIQ scores was continuing seizures, which was more frequent in the NDTL group. Conclusions: In this study, the main finding was cognitive stability from 2 to 10 years after temporal lobe resection. There was no further decline in verbal memory from 2 to 10 years after surgery, lending no support to the notion of an ongoing progressive decline in verbal memory after temporal lobe resection. The verbal memory course was not dependent on seizure outcome or antiepileptic drug treatment.

Verbal memory decline and adverse effects on cognition in adult patients with pharmacoresistant partial epilepsy : a longitudinal controlled study of 36 patients

The aim of this study was to delineate possible longitudinal cognitive changes in adult patients with a long history of pharmacoresistant partial epilepsy. Thirty-six patients and thirty healthy controls were investigated at baseline. A reassessment was conducted, with median test intervals of 4.8 years for the patients and 3.1 years for controls. A standardized battery was used for assessment of general cognitive level and memory. At baseline, patients performed at a significantly lower level on general cognition, immediate recall of pairs of associated words, and retention of learned words and visuospatial stimuli, compared with controls. Analyses of change over time in the patients disclosed significant verbal memory decline in retention of pairs of associated words. Group comparisons of change over time revealed adverse effects in the performance aspect of general cognition on the patients. Also, group comparisons indicated impaired performance across time for the patients in retention of pairs of associated words and retention of visuospatial stimuli. The adverse effect on memory and general cognition in this patient group over the period was clear-cut when compared with the longitudinal changes in an adequate control group.

Serial cognitive change patterns across time after temporal lobe resection for epilepsy

Longitudinal cognitive outcome with respect to general cognitive status and memory at the group and individual levels was studied 10 years after temporal lobe resection for epilepsy. Twenty-five patients who had undergone a medium-term follow-up (T2, median = 2.7 years) also underwent a long-term follow-up (T3, median = 9.8 years). At the group level, there was a significant increment across time, partly due to practice, in IQ (P value from 0.049 to <0.0001) but not in memory variables. On the basis of the normative interval of reassessed matched controls, the analysis at the individual level of change from baseline to T2 disclosed decrements in 12-29% of the patients and increments in 8-21%. These proportions diminished at T3 (0-12 and 0-16%) and the dominating pattern of Performance IQ and verbal memory was a return toward baseline. These findings make the interpretation of an initial (T2) postoperative increment or decrement more problematic and underline the need for a comprehensive evaluation across time, including both at the group and individual levels.

Non-parametric Evaluation of Memory Changes at Group and Individual Level Following Temporal Lobe Resection for Pharmaco-resistant Partial Epilepsy

ABSTRACT Group versus individual verbal and visuospatial memory outcome following epilepsy surgery was evaluated by a non-parametric method in 25 left and 29 right temporal lobectomy patients. Twenty-five controls were assessed twice. Analyses of change at an individual level evaluated by this statistical approach based on paired-ranks were compared to results with a method based on distances (Reliable Change). The left temporal lobectomy group deteriorated in the two verbal memory variables (p < 0.01 and 0.05). High levels of individual changes unexplained by group patterns were disclosed in the three memory variables analyzed in the patients. Significant individual change, although less pronounced, also occurred in the controls. Group versus individual outcome was adequately distinguished by the non-parametric method. To properly analyze memory change after epilepsy surgery, evaluation at group and individual level ought to combined.

Verbal memory decline is less frequent at 10 years than at 2 years after temporal lobe surgery for epilepsy.

We investigated individual short- and long-term verbal memory changes after temporal lobe resection for epilepsy. Fifty-one patients (23 operated on the speech-dominant temporal lobe, DTL and 28 on the non-dominant temporal lobe, NDTL) were tested on learning/immediate recall and delayed recall of word-list and word-pairs preoperatively, 2 years postoperatively and 10years postoperatively. Changes were defined using reliable change indices of 23 healthy controls assessed at corresponding intervals. Fewer patients had reliable declines at 10 years than at 2 years (DTL: 13-35% vs 35-44%; NDTL: 0-4% vs 7-21%). Four DTL patients (17%) had reliable declines in ≥2 tests at 10-year follow-up. More NDTL patients had improvement at 10 years than at 2 years (18-30% vs 4-22%). The only risk factor for decline both short and long term was DTL resection. In conclusion, most patients had stable verbal memory postoperatively. A few DTL patients had a lasting decline at long-term follow-up, but more patients showed partial recovery, especially in the NDTL group.

Psychosocial status 10 years after temporal lobe resection for epilepsy, a longitudinal controlled study

Knowledge about long-term psychosocial outcome of temporal lobe resection (TLR) for epilepsy is limited. The aims of this study were to describe vocational outcome 10 years after TLR and to analyze the effect on the vocational situation by seizures, laterality of resection, verbal memory, and mood. Fifty-one patients were prospectively followed 10 years after TLR. Psychosocial and neuropsychological data were ascertained at baseline and 10 years after surgery and at corresponding time points for 23 controls. Fewer patients worked 10 years post-operatively compared with controls (TLR patients: 61% and controls: 96%). However, seizure-free patients were more likely to retain employment (71%) than patients who had seizures (41%). The odds of working full-time were 9.5 times higher for patients with seizure freedom than for those with continuing seizures. There were no associations between working at 10 years and side of resection or mood, and impairment of verbal memory did not have an influence on vocational outcome.

Verbal cognition and attention deficits do not explain the verbal memory decline associated with pharmacoresistant partial epilepsy

The aim of this study was to explore whether change in verbal memory with time in patients with epilepsy is influenced by performance on tasks assessing verbal cognition or attention/processing speed. Thirty-six patients and twenty-five healthy controls were tested twice with median retest intervals of 4.8 and 3.1 years, respectively. Aspects of verbal memory, verbal cognition, and attention/processing speed were assessed. Decline in one verbal memory variable (Cronholm-Molander Memory Test Paired Associates -- Delayed Recall) was the strongest correlate of epilepsy. The second strongest correlate was a decrease in one attention/processing speed variable (Digit Symbol). The relationship between decline in verbal memory and epilepsy was not influenced by the decline in attention/processing speed, and the results did not support the notion that limited mental reserves as reflected in impaired verbal cognition or attention/processing speed can explain the relationship between verbal memory and epilepsy.

A longitudinal study of psychological features in patients before and two years after epilepsy surgery.

This study aimed at investigating psychological features before and two years after epilepsy surgery. Fifty patients, 39 with temporal lobe epilepsy (TLE) and 11 with frontal lobe epilepsy (FLE), were assessed at baseline and two years postoperatively with the Karolinska Scales of Personality (KSP). Baseline group level outcome was normal while individual level analyses delineated some mild to moderate degrees of psychological problems exceeding the normal range in subsets of patients. Features of hostility characterized half of the FLE and one-fourth of the TLE patients. Above 1/3 in each group had dependency features. About 1/3 of the TLE patients suffered from psychasthenia. In conclusion, even though group levels were normal, several patients had psychological problems. The main longitudinal result was that the personality features were stable and did not change after epilepsy surgery.

Successful epilepsy surgery in a patient with neurosarcoidosis.

This case concerns a patient with generalized neurosarcoidosis and pharmacoresistant focal epilepsy. Although immunosuppressive therapy resulted in remission of the neurosarcoidosis, seizures continued and were shown to originate from the right temporal lobe (TL). The patient underwent a right anterior temporal lobe resection (TLR) and obtained >90% reduction of seizure frequency.