Surgery-Independent Language Function Decline in Patients Undergoing Awake Craniotomy.

BACKGROUND: Despite selection process before awake-craniotomy, some patients experience an unexpected decline in language functions in the operating room (OR), compared with their baseline evaluation, which may impair their functional monitoring. To investigate this phenomenon we prospectively compared language function the day before surgery and on entrance to the OR.

METHODS: Data were collected prospectively from consecutive patients undergoing awake-craniotomy with intraoperative cortical mapping for resection of gliomas affecting language areas. Language functions of 79 patients were evaluated and compared 1-2 days before surgery and after entering the OR. Changes in functional linguistic performance were analyzed with respect to demographic, clinical, and pathologic characteristics.

RESULTS: There was a significant decline in language function, beyond sedation effect, after entering the OR, (from median/interquartile range: 0.94/0.72-0.98 to median/interquartile range: 0.86/0.51-0.94; Z = -7.19, P < 0.001). Univariate analyses revealed that this decline was related to age, preoperative Karnofsky Performance Scale, tumor location, tumor pathology, and preexisting language deficits. Multivariate stepwise regression identified tumor pathology and the presence of preoperative language deficit as significant independent predictors for this functional decline.

CONCLUSIONS: Patients undergoing awake-craniotomy may experience a substantial decline in language functioning after entering the OR. Tumor grade and the presence of preoperative language deficits were significant risk factors for this phenomenon, suggesting a possible relation between cognitive reserve, psychobehavioral coping abilities and histologic features of a tumor involving language areas. Capturing and identifying this unique population of patients who are prone to experience such language decline may improve our ability in the future to select patients eligible for awake-craniotomy.