Study On Quantitative Electroencephalographic Reactivity In Prognosis Of Critical Cerebral Vascular Disease

Objection We assessed EEG reactivity of acute CVD coma patients to compare visual analysis of reactivity with quantitative analysis of reactivity. The purpose of the study was to determine whether quantitative analysis of reactivity is more exactly to assess prognosis than visual analysis of reactivity. Method Fifty-six acute CVD coma patients were selected for this study. Sixteen channels of EEG were recorded with a VISH Digital EEG. EEG was monitored on admission, a week after admission and leave hospital. Visual analysis of reactivity and external stimulus-induced percentage of absolute power changes were observed. Differences in the mean percentage of absolute power changes in different brain region, and between the affected and unaffected hemispheres, and between different outcomes of patients were compared by the ANOVA. Relationship between percentage of absolute power changes and visual analysis of reactivity and GCS score were evaluated by correlation analysis and multiple linear regression analysis. Result 1. Visual analysis of EEG reactivity (1) Visual analysis of reactivity displayed three forms: increase in quantity and amplitude of δ,θ(19 case); increase in quantity of δ,θ(10 case); increase in quantity of δ,θand amplitude of all activities(11 case). (2) Pain-induced percentage of reactivity was higher (71%~94%) than auditory reactivity (11%~14%) and visual reactivity (0%~8%) (P<0.01). (3) It was significant difference between reactivity and no reactivity in outcome of patients (P<0.01). 2. Quantitative analysis of EEG reactivity (1) Absolute power of each frequent band increased to painful stimulus, especially delta and theta bands (P<0.01). (2) It was significant difference in different outcomes of patients in pain-induced percentage of absolute power changes of admission EEG (P<0.01). (3) The correlation was significantly obtained between pain-induced percentage of absolute power changes and GCS score on admission, a week after admission and leave hospital (P<0.01). (4) It was not significant difference in different brain region, and between the affected and unaffected hemispheres in percentage of absolute power changes (P>0.05). 3. Multiple linear regression analysis pain-induced percentage of absolute power changes of delta band and visual analysis of reactivity significantly associated with GCS score(P<0.01). The correlation of between percentage of absolute powerchanges of delta band and GCS score was more intensive than visual analysis of reactivity(δt 6.21> visual t 5.75). Conclusions Visual analysis of EEG reactivity and quantitative analysis EEG reactivity were good factors to assess prognosis of CVD coma patient. Pain-induced percentage of reactivity was higher. Absolute power of each frequent band increased to external stimulus, especially delta and theta bands. The patients with absolute power of each frequent band increased had good outcome. The degree of absolute power increased was higher the outcome of patients was better. Quantitative analysis of EEG reactivity was more exactly to assess prognosis than visual analysis of EEG reactivity.