SELECTIVE AMOBARBITAL TEST FOR THE DETERMINATION OF LANGUAGE FUNCTIONIN PATIENTS WITH EPILEPSY WITH FRONTAL AND POSTERIOR TEMPORAL BRAIN-LESIONS

Purpose: Selective amobarbital tests with selective temporary inactiva tion of the left frontal operculum and/or the left parietotemporal cor tex were performed in 5 patients with left-hemispheric epileptogenic l esions in or adjacent to classical Broca's and/or Wemicke's area. The aim was to assess language functions in these brain regions before sur gery, to tailor the surgery according to the individual functional imp ortance of these brain regions, and to predict postoperative outcome. Methods: Amobarbital was injected by transfemoral selective catheteriz ation of the arteries supplying the target areas. Along with neuropsyc hological and neurological testing during the amobarbital procedure, E EG recordings were performed in all patients, and [Tc-99m]HMPAO-single photon emission computed tomography (SPECT) in 2 patients. Results: A fter the amobarbital injection into the left frontal opercular region, there was no recognizable language dysfunction in 3 patients. In thes e 3 patients, the lesions in or adjacent to the frontal operculum were completely resected without postoperative language impairment. In the remaining 2 patients, temporary language impairment after the amobarb ital injection into the left frontoopercular and Wernicke's region, re spectively, suggested language functions in these areas. Surgery was r estricted to the left mesiotemporal lobe in 1 patient. In the other pa tient, the tumor infiltrating the frontal operculum was restrictively resected. Postoperatively, the first patient had no language impairmen t, but the latter had transient global aphasia, from which she recover ed. Conclusions: Selective temporary amobarbital inactivation of brain regions that may be associated with language has clearly indicated th e presence or absence of language functions in these regions. The test contributed substantially to planning of the surgical approach in eac h patient. The predictive value of the amobarbital test was demonstrat ed by the postoperative outcome.