Abstracts

RATIONALE: In addition to traditional visual naming sites in language dominant temporal cortex, we, and others, have identified sites where stimulation disrupts auditory naming (e.g., [dsquote]The yellow part of an egg[dsquote]), yet does not interfere with visual (picture) naming. However, it is currently unknown whether it is necessary to spare auditory naming sites from resection in order to preserve language function postoperatively. We hypothesized that resection of auditory naming sites would result in postoperative auditory naming decline, whereas sparing these sites would preserve word finding ability.
METHODS: Subjects were 16 left TLE patients who underwent preoperative cortical language mapping (7 intraoperative, 9 extraoperative) utilizing both visual and auditory naming tasks. Surgical resections were carried out regardless of auditory naming data. Auditory naming sites were spared in 7 patients, resected in 6 patients, and fell within 2 cm from the resection boundary in 3 patients. Visual naming sites were preserved in all patients. All patients underwent extensive testing of word finding before surgery and one year postoperatively. Naming tasks included a 50-item auditory description naming task, a 50-item visual naming task, and the Boston Naming Test (BNT). Performance measures included accuracy, RT and tip-of-the-tongue scores for the auditory and visual naming tasks, and accuracy scores for the BNT. Reliable change indices were calculated for all 7 word finding measures to identify significant postoperative change. Fisher[ssquote]s exact test was used to determine whether auditory naming site resection was associated with postoperative naming decline (i.e., significant decline on at least one naming measure).
RESULTS: None of the 7 patients in whom auditory naming sites were spared declined on any naming measure, whereas 5 of the 6 patients in whom auditory naming sites were resected declined on at least one naming measure (p [lt] 01). Two of the 3 patients in whom auditory naming sites fell within 2 cm from the resection boundary each declined on one measure. Most intriguing, significant decline was evident on visual naming as well as auditory naming measures, despite the fact that visual naming sites were preserved in all patients.
CONCLUSIONS: These preliminary findings suggest that sparing auditory naming sites preserves postoperative word finding, whereas resecting these sites causes a fairly general word finding decline. These results might also explain why patients whose resections are tailored based on mapping using solely visual naming sometimes show word finding decline postoperatively (i.e., untested auditory naming sites may have been removed).
[Supported by: National Institute of Neurological Disorders and Stroke, Grant Number: NS35140-01A1.]