VERBAL MEMORY AFTER TEMPORAL LOBE EPILEPSY SURGERY
Abstract number :
2.413
Submission category :
Year :
2003
Submission ID :
669
Source :
www.aesnet.org
Presentation date :
12/6/2003 12:00:00 AM
Published date :
Dec 1, 2003, 06:00 AM
Authors :
Leena Jutila, Heleena Hurskainen, Reetta Kälviäinen, Marja äikiä, Esa Mervaala, Juhani Partanen, Matti Vapalahti, Arto Immonen, Aarne Ylinen Department of Neurology, Kuopio University Hospital, Kuopio, Finland; Department of Neurosurgery, Kuopio Universit
The aim of the study was to assess verbal memory performance after temporal lobe epilepsy (TLE) surgery.
Patients were retrieved from a series of 140 consecutive adult patients, operated on at Kuopio University Hospital between 1988 and 1999 because of drug resistant TLE. The long-term surgical outcome in these 140 patients has been published previously (JNNP 2002;73:486-494). Altogether 103 patients in the original series had unilateral TLE, and 76 of them had completed the long-term neuropsychological follow-up. Patients with right-sided speech dominance and patients with full scale IQ less than 70 were excluded. Neuropsychological evaluation was performed preoperatively (median 6.7 months), one year postoperatively (median 12.3 months) and two (n=10) or three (n= 66) years postoperatively (median 37.3 months). Altogether 34 patients had seizure onset on the left and 42 on the right. Distribution of males and females was unequal between the TLE groups (p[lt]0.05). Verbal IQ was lower in the left TLE group when compared to the right TLE group (p[lt]0.05). Meaningful change in postoperative test performance was defined as one standard deviation (SD) from the baseline.
When evaluated with ANOVA for repeated measurements, the performance in the WMS Logical Prose (the immediate and delayed recall) remained stable during the follow-up. However, there was a significant decrease at group level both in the learning and in the delayed recall of words the WMS Associate Learning task during the follow up (p[lt]0.05 in all). One year after the operation 30% of left TLE patients (n=9) and 7% of right TLE patients (n=3) had a meaningful decrease from the baseline scores in delayed recall of words in the Associate Learning Task. Respectively, at the end of the follow-up 56% of left TLE patients (n=19) and 33% of right TLE patients (n=14) had a meaningful decrease from the baseline scores in delayed recall of words in the Associate Learning task.
Surgery is an effective treatment for drug-resistant TLE in adults. However, the occurrence of material specific memory decline in the test performance after surgery seems to increase in the extended follow-up. The clinical significance of this finding over longer periods of time remains to be seen.
[Supported by: Academy of Finland, Finnish Cultural Foundation, Kuopio University Hospital Research Fund (EVO 577 2719), University of Kuopio, and Vaajasalo Foundation. ]