The Prospective Cohort Study Of Quantitative EEG Parameters To Predict The Prognosis Of Patients With Large Hemispheric Infarction

Part One The correlation analysis between quantitative EEG param-eters and midline shift and infarct volume of patients withlarge hemispheric infarctionObjective: Quantitative electroencephalography(QEEG)data are helpful to predict the prognosis of patients with large hemispheric infarction(LHI).The purpose of this study was to establish a prospective cohort of LHI,to study the correlation between QEEG parameters and radiographic indexes(infarct volume,midline shift)in patients with LHI.Methods: We studied a prospective,consecutive series of patients with large hemispheric infarction diagnosed by cranial CT or MR from two neurological intensive care units in Beijing Tiantan Hospital from August2017 to October 2017 and the Second Hospital of Hebei Medical University from November 2017 to February 2020.The inclusion criteria were:(1)patients older than 18 years old;(2)patients admitted to neurointensive care unit within 3 days of stroke onset.(3)CT or MRI showed that the infarction involved at least 2 thirds of the middle cerebral artery territory.The exclusion criteria were as follows:(1)multiple cerebellar,brainstem or bilateral cerebral hemispheric infarction;(2)received antiepileptic drugs or sedatives that may affect EEG activity within 24 hours before EEG monitoring;(3)MRS ≥ 2;(4)major diseases that seriously affected the prognosis,such as severe heart failure.Use a digital video-EEG monitor(Nicolet Monitor,Natus (?),USA))for at least 2 hours at a time,within 4 hours before or after the head CT scan,and each patient can be monitored multiple times.The continuous 30 min EEG data without artifacts were selected and quantitatively analyzed by MATLAB R2015a(Math Works,Inc.MA,USA)software and its EEGLAB toolbox.The ratio of frequency band(delta [1-4 Hz],theta [4-8 Hz],alpha [8-12.5 Hz],beta[12.5-30 Hz])to total power was calculated.The delta/alpha ratio(DAR)and the(delta+theta)/(alpha+beta)ratio(DTABR)are calculated according to the above frequency bands.The Brain symmetry index(BSI)frequency band is(1-30Hz).Use Philips brilliance scanner(Philips,Amsterdam,Netherlands)and Med Viewer software with a thickness of 5 mm.In the process of detection,the lesion area was delineated layer by layer,and the volume was calculated by multiplying the total lesion area by layer thickness and layer spacing.The midline shift is measured at the level of the pellucid septum.Results: Thirty-one patients with LHI underwent 40 times of EEG monitoring,including 25 males and 16 females,with an average age of 66 years.19(61.3%)patients had left hemispheric infarction.The average infarct volume was 427.9 ml,the median midline shift was 4.9 mm.Only BSI was correlated with infarction volume,but the correlation was weak(r = 0.334),and the difference was statistically significant(P = 0.037).There was no correlation between other QEEG parameters and radiological indexes.Conclusions: The results showed that there was a positive correlation between BSI and infarct volume in LHI population,and the correlation was weak.Part Two The value of Brain symmetry index in predicting the poor prognosis of large hemispheric infarctionObjective: Quantitative electroencephalography(QEEG)data are useful to predict outcomes of large hemispheric infarction(LHI)patients.The study was performed to evaluate the value of QEEG parameters in predicting3-month non-suivival outcome of LHI.Methods: We studied a prospective,consecutive series of patients with LHI confirmed within three days from onset in two neurological intensive care units in Beijing Tiantan Hospital from August 2017 to October 2017 and the Second Hospital of Hebei Medical University from November 2017 to February 2020.The electroencephalography(EEG)was recorded at admission.The QEEG parameters including alpha power,beta power,delta power,theta power,DAR,DTABR and BSI were calculated.The primary outcome was non-survival at 3-months after the onset.The second outcome was midline shift ≧5mm.Results: A total of 38 patients were included.The subjects were divided into non-survival group(fifteen patients)and survival group(twenty-three patients).There was no difference in baseline variables between these two groups.Of the QEEG parameters,only a higher BSI was noticed in the non-survival group than that in the survival group at 3 months(P=0.029).Multivariable analysis indicated that BSI was an independent predictor of3-month non-survival outcomes(OR=18.389,CI95% 1.121,307.152,P=0.041).The sensitivity,specificity,positive predictive value,and negative predictive value of BSI to predict 3-month non-survival was 93.3%,47.8%,53.8%,91.7%,respectively(AUC = 0.719,P = 0.024).There was no difference in QEEG between midline shift ≧5mm group and <5mm group.Conclusions: BSI had predictive value in predicting LHI death outcomes at 3 months.Larger clinical trials are still needed.Part Three The change index of QEEG for evaluating the prognosis of large hemispheric infarctionObjective: A growing number of studies have demonstrated the role of quantitative electroencephalography(QEEG)in assessing brain function in neuro-intensive care units,but few studies have examined patients with large hemisphere infarction(LHI).Methods: From August 2017 to July 2020,30 patients with LHI were included in this prospective study,and the patients were divided into death group(twelve patients)and survival group(eighteen patients).EEG monitored the patients,and CT inspection was performed.The QEEG of Alpha,Beta,Delta,and Theta power ratio(ABDTR)change index were calculated and used to predict the early LHI patients’ prognosis.The relationship between three months modified Rankin Scale(m RS),and ABDTR change index were analyzed.Results: The death group had negative changes for ABDTR change index(-0.0140 ± 0.0193),while there was an opposite trend in the survival group,the median is 0.004(-0.0067,0.0137).The death group’s brain function decreased more severely and rapidly than the survival group(P = 0.004).The highest diagnostic value(AUC value 0.815,P<0.001)was observed when the ABDTR change index dropped and exceeded-0.008.The area under the GCS curve was 0.674,but its predictive ability was low(P = 0.094).The correlation analysis result showed that the 3-month m RS was negatively correlated with the ABDTR change index(r=-0.489,P=0.006).Conclusions: ABDTR change index may be a valuable predictor of LHI prognosis.ABDTR have the value of real-time monitoring the changing trend of patients with LHI.A multi-center clinical trial will be required in the future to verify the results of this trial.Conclusions:1.There is a correlation between BSI and infarct volume,suggesting that BSI could indirectly indicate the size of infarction volume in LHI patients to guide clinical evaluation.2.BSI of QEEG parameters can predict the death outcome of LHI patients at 3 months,suggesting that early QEEG parameters have the prognostic value of LHI patients.3.ABDTR change index may be a valuable predictor of LHI prognosis,and its predictive value is higher than that of GCS score.ABDTR have the value of real-time monitoring the changing trend of patients with LHI.