A COMPARISON OF QEEG AND HMPAO-SPECT IN RELATION TO THE CLINICAL SEVERITY OF ALZHEIMERS-DISEASE

Electroencephalographical studies have disclosed correlations between topographical features of Fast Fourier Transformation maps and the sev erity of Alzheimer's disease (DAT). The object of the present study wa s to explore the relations of HMPAO-SPECT and quantitative EEG (qEEG) with the severity of dementia. Twenty-three patients were included in the study. Spectral and topographical EEG parameters were compared wit h global and regional cerebral blood flow, and with psychometric measu res of clinical serverity. None of the regions of interest of the SPEC T scans were significantly correlated with clinical severity. Low valu es in delta-and theta-bands, however, were related to high scores on t he Mini-Mental-State examination (P < 0.01), whereas the Syn drom-Kurz test correlated inversely with the power values in the alpha and beta band. The global decrease in cerebral blood flow (CBF) was associated with a shift on the topographical alpha-centroids in the posterior di rection (P < 0.01). In previous studies correlations between CBF and c linical severity were weak, indicating a high interindividual variance , or interactions with concomitant vascular lesions. Whereas SPECT is a well-established tool for the diagnosis of dementia, the present stu dy indicates qEEG as a potential marker for the staging of the cogniti ve decline in DAT.