SIR Medicine Investigation Abstract
ASSESSING LOCAL BRAIN FUNCTION WITH QUANTITATIVE EEG AND CONVENTIONAL EEG IN CORRELATION WITH SPECT SCANS IN PATIENTS WITH CEREBRAL INFARCTION
Presenter:
Aiva M. Ievins, Illinois Mathematics and Science Academy
Advisor:
Dr. Teresa Poprawski, Hines Veterans Administration Hospital
Abstract:
Stroke is one of the main causes of neurological disabilities. Therefore, it is very important to evaluate patients with techniques that accurately assess brain function. It has been reported that brain electrical activity is related to cerebral blood flow. We performed this study to determine and compare the accuracy of conventional EEG and qualitative EEG in evaluating this relationship.
Six patients (age 65 +/- 12) with diagnosis of cerebral infarction (death of tissue due to obstruction of local blood supply) were studied with conventional EEG, qEEG, and HMPAO based SPECT. SPECT analysis was conducted by means of SPM 99 and qEEG data was analyzed by standardized protocol involving the Neuroguide database. Correlations between SPECT findings and qEEG absolute and relative powers were evaluated.
Conventional EEG was non-localizing upon visual inspection. However, considerable correlations between regional brain activity and perfusion were found with qEEG and SPECT. Brain areas with significantly decreased perfusion on the SPECT scan showed increased "slow" activity (delta and theta frequencies) and decreased "fast" activity (alpha and beta frequencies) in qEEG analysis. Areas of increased perfusion on the SPECT scan were associated with an increase in beta activity in qEEG.
These findings demonstrate the relationship of cerebral blood flow with regional brain activity and indicate that qEEG results based upon a comparison against a normal database more accurately reflect local brain function that parallels SPECT findings than conventional EEG.