Visual naming performance after ATL resection: impact of atypical language dominance.

PURPOSE To characterize the interaction between language dominance and lateralization of the epileptic focus for pre- and postoperative Boston Naming Test (BNT) performance in patients undergoing anterior temporal lobectomy (ATL). METHODS Analysis of pre- and postoperative BNT scores depending on lateralization of language as measured by the intracarotid amobarbital procedure (IAP) versus lateralization of the temporal lobe epileptic focus. RESULTS Changes between pre- and postoperative BNT performance depended on epilepsy lateralization (effect size=0.189) with significant decrease in patients undergoing left ATL. Subgroup analysis in these showed that postoperative decline in BNT scores was significant in patients with atypical (n=14; p<0.05), but did not reach statistical significance in patients with left language dominance (n=36; p=0.09). Chi-square test revealed a trend of higher proportions of patients experiencing significant postsurgical deterioration in naming performance in atypical (57.1%) as compared to left language dominance (30.6%; p=0.082). Surgical failure was also associated with greater decline of BNT scores and was more common in atypical than in left language dominant patients (chi(2) (1, n=98)=4.62, p=0.032). Age of onset, duration of epilepsy, and seizure frequency had no impact on changes in BNT performance. CONCLUSION Atypical language dominance is a predictor of change in visual naming performance after left ATL and may also impact postsurgical seizure control. This should be considered when counseling surgical candidates.