PREDICTORS OF LANGUAGE OUTCOME
FOLLOWING DOMINANT ANTERIOR TEMPORAL LOBECTOMY (ATL)

To be presented to the Annual Meeting of the American Epilepsy Society, December, 2000

Karen J Kluin, Erasmo A Passaro, Ekrem Kutluay, Donald A Ross, Henry A Buchtel, Ahmad Beydoun, Univ of Michigan, Ann Arbor, MI

RATIONALE: Language deficits are a postoperative complication following dominant ATL. Boston Naming Test (BNT) scores decrease in the early postoperative period in a substantial proportion of patients; however, language function improves in some patients at one year. We evaluated if certain variables were predictive of language outcome at one year following surgery.

METHODS: We included 39 patients who underwent dominant ATL with language mapping and who had language evaluations preoperatively, and at 2 months and 12 months postoperatively. Patients were divided into three groups: a) no significant decline (less than 5 points) in BNT scores at 2 months compared to baseline; b) significant decline at 2 months without significant improvement at one year; c) significant decline at 2 months with significant improvement at one year. Groups b and c were compared by ANOVA and Fisher test for age at time of surgery, baseline BNT scores, absolute and relative (%) decreases in BNT scores at 2 months, and type of language mapping. p values < 0.05 were considered significant.

RESULTS: 41%,15% and 44% of the patients were in groups a, b and c respectively. There was a significant reduction in BNT scores at 2 months compared to both baseline and 1 year, but no significant difference between baseline scores and 1 year. For group a, there was no significant difference in BNT scores between 2 months and 1 year. For groups b and c, there was no significant difference in baseline BNT scores or the absolute and relative decreases in BNT scores. In group b, there was a trend for older age at the time of surgery (p=0.08). More patients in group c underwent intra-operative language mapping compared to group b, but the difference was not significant.

CONCLUSIONS: Patients without a significant decline in BNT scores at 2 months may not require follow-up testing at 1 year. More than half of the patients had a significant decline in their BNT score at 2 months. Baseline BNT scores and absolute and relative decreases in BNT scores at 2 months are not predictive of improvement at one year. Patients with a significant decrease in their BNT score at 2 months are less likely to recover if they are older at the time of surgery.


15 July 2000)