Abstract
The aim of this study was to elucidate whether electroencephalograms (EEG) and/or somatosensory evoked potentials (SEP) deteriorates after the acetazolamide injection in patients with major cerebral artery occlusion. So far as we know, the study reported here is the first designed to clarify the effect of acetazolamide on EEG and SEP.
Twenty-three patients with unilateral supratentorial ischemic stroke were subjected to the study at least one month after onset. They were composed of 7 cases without detectable occlusion or stenosis, and 16 cases with occlusion of the major cerebral artery (internal carotid artery or trunk of the middle cerebral artery). Loading dose of acetazolamide was 500 mg in the former group, and 500 mg or 20 mg/kg in the latter.
Sixteen-channel EEGs before and after injection of acetazolamide were evaluated quantitatively by means of power spectral analysis. The relative power of the spectrum (% of total EEG power) in delta, theta, alpha, beta bands were calculated. The principal component analysis was applied to a correlation matrix of relative powers and recording positions in each band. The t-profiles were then produced using principal component scores. The t-profiles revealed that the acetazolamide had no significant influence upon EEG activities, regardless of the dosage and angiographic findings.
SEP changes were evaluated by the difference of peak latencies of corresponding components before and after injection of acetazolamide (ΔP.L). To assess the effect of acetazolamide injection on the latencies of individual SEP component in the patients with major cerebral artery occlusion, the values of mean ± 2S.D. of ΔP.L in the cases without occlusion were determined as the upper and lower limits of variation. However, no significant changes of ΔP.L were denoted in the patients with major cerebral artery occlusion.
In 3 out of 16 cases with major cerebral artery occlusion, however, significant flow distribution changes were exhibited by IMP-SPECT after the acetazolamide injection.
Our investigations suggest that acetazolamide has no pharmaco-encephalographical charactristic and its application to the 3-dimentional CBF study reveals a region with reduced vasodilatory capacity without any affection nor deterioration of EEG and SEP.
