Prognostic Assessment Of Patients With Ischemic Stroke Caused By Middle Cerebral Artery Stenosis Based On Automatic Measurement Of ADC And CBF Values In MCA-Alberta Stroke Program Early CT Score

Part 1 Quantitative Research of Normal Cerebral Blood Flow Based on Automatic Measurement in MCA-Alberta Stroke ProgramEarly CT Score AreaObjective: To explore cerebral blood flow(CBF)value,investigate the difference index of CBF between left and right brain and compare the CBF values via automatic measurement based on MCA-ASPECTS(Middle Cerebral Artery-Alberta Stroke Project early CT Score),as well as to study the relationship between age and CBF values in different MCA-ASPECTS regions among healthy people.Methods: 22 healthy volunteers(8 males and 14 females,aged 21 ～ 66(40.71±14.58 years)were recruited in the study.The brains of all subjects were scanned on GE Signa HDxt 3.0 T MRI scanner in our hospital,using conventional head MRI sequence,3D ASL(three-dimensional arterial spin labeling)and MRA(magnetic resonance angiography)sequences.After image registration of cerebral blood flow image,CBF value of the middle cerebral artery in each APECTS region was calculated to obtain the left and right brain CBF difference index.A paired T-test was used to compare CBF differences in the left and right ASPECTS areas,including M1,M2,M3,M4,M5,M6,Insula、Lentiform Nucleus、Caudate、Internal Capsule.The CBF values of MCA-ASPECTS were also analyzed by variance analysis for every region to detect the differences among the regions.The differences between every two groups were compared using Tukey HSD.Pearson correlation coefficient was used to analyze the relationship between CBF values and age.Results: The CBF value difference of Insula,M1,and M4 between left and right brain were statistically significant(P<0.05).The highest CBF in MCA-ASPECTS region was the bilateral M3 region and right Insula region.The lowest CBF was the bilateral Internal Capsule region.The M1 region with the greatest CBF difference index was 0.061±0.038.The M2 region(lateral cortex)had the least CBF difference index,with an average of 0.022±0.020.The CBF values of ten regions in the bilateral MCA-ASPECTS area were statistically significant(P<0.001).The difference between the majority of every two MCA-ASPECTS areas were statistically significant(P<0.05).The CBF value of bilateral Insula region,bilateral M2 region,left Caudate(Caudate lobe)region,and right M1 region were negatively correlated with age with statistical significance(P <0.05).The CBF value of the Internal Capsule region on the right brain was positively correlated with age,the correlation coefficient was 0.4 and P <0.05.Conclusion: CBF value was different in bilateral brain regions and ten MCA-ASPECTS regions in normal adults.Age has an obvious influence on CBF value in some brain regions.The Automatic measurement technology can detect CBF in different brain regions of normal people and can provide a new method for the clinical evaluation of cerebrovascular diseases.Part 2 Quantitative Research of ADC Value Based on Automatic Measurement in MCA-Alberta Stroke Program Early CT ScoreObjective: To explore apparent diffusion coefficient(ADC)value,relative ADC(r ADC)value,ADC difference among MCA-ASPECTS regions,as well as to study the relationship between ADC and age in different MCA-ASPECTS regions among healthy people.Methods: 22 healthy volunteers(8 males and 14 females,aged 21~66(40.71±14.58 years)were recruited as study subjects.The brains of all subjects were scanned through GE Signa HDxt 3.0 T MRI scanner in our hospital,using conventional head MRI sequence,3D ASL and MRA sequences.Diffusion-weighted imaging was obtained,and then ADC imaging was reconstructed.After image registration,data of MCA-ASPECTS regions were extracted for data analysis.Value of ADC and r ADC from healthy volunteers in each MCA-ASPECTS region were also obtained.A paired t-test was used to compare the difference between left and right ASPECTS regions.Variance analysis was used to analyze the difference among MCA-ASPECTS regions.Tukey HSD was used to compare the difference between every two groups.Pearson correlation coefficient was used to analyze the relationship between ADC value and age.Results: There was no significant difference between bilateral cerebrum ADC value in MCA-ASPECTS regions(P > 0.05),but the ADC value in bilateral cerebral cortex area(Insula,M1~M6)was higher than bilateral basal ganglia area(Caudate,Lentiform Nucleus and Internal Capsule).The greatest r ADC value was in M2 region(1.016±0.023),and the smallest was M1 region(mean±standard deviation 1.000±0.024).There was a significant difference in ADC values among ten regions of MCA-ASPECTS(P < 0.001).Tukey HSD was used to compare the difference between every two group in ten different regions.There was a significant difference in most of the MCA-ASPECTS regions between every two groups(P < 0.05).The ADC values of right Insula and bilateral M3 regions were positively correlated with age,the correlation coefficient were 0.36,0.49,0.38,0.54,respectively,while the ADC values of bilateral Caudate areas were negatively correlated with age,thecorrelation coefficient were-0.42,-0.32 respectively.Conclusion: There was no significant difference in the ADC values of the MCA-ASPECTS regions between the bilateral brain of normal adults,but there was significant difference in the ADC value among different MCA-ASPECTS regions.Age has an effect on ADC in some brain regions.The Automatic measurement technology can obtain ADC value in different brain regions of normal people and can provide a new method for clinical evaluation of cerebrovascular diseases.Part 3 Prognostic Assessment of Patients with Ischemic Stroke Caused by Middle Cerebral Artery Stenosis Based on Automatic Measurement of ADC and CBF Values in MCA-Alberta Stroke Program Early CT Score AbstractObjective: to explore the clinical value of automatic measurement of ADC and CBF value based on MCA-ASPECTS area in evaluating the prognosis of patients with ischemic stroke caused by middle cerebral artery stenosis.Methods: 32 patients with ischemic stroke caused by unilateral middle cerebral artery stenosis were analyzed retrospectively through 3D-TOF-MRA from January 2018 to July 2020,including 24 males and 8 females,age from 31 to 82 years old(62.71 ±11.90 years).All patients were scanned routine MR,3D-TOF-MRA and 3D ASL sequences.Grayscale of CBF was obtained by Functool software.Two different b value of diffusion-weighted imaging were subtracted and calculated to get ADC map.CBF grayscale and ADC map were registered to the standard brain(MNI)template and were obtained mean CBF and ADC value of each ASPECTS region.Using linear regression model,the relationship between CBF value from MCA-ASPECTS regions and prognosis score(change of NIHSS score at admission and discharge)were analyzed for patients with selected sex,age,and therapy before and after treatment,and between the stroke affected hemisphere and the contralateral side.Chi-square test was used to analyze the correlation between change of number of MCA-ASPECTS abnormal regions and change of NIHSS score(admission and discharge)before and after treatment in DWI-ASPECTS(number of abnormal MCA-ASPECTS areas on DWI image),Manual-ASL-ASPECTS(number of abnormal MCA-ASPECTS regions was measured manually CBF value)and Auto-ASL-ASPECTS(number of abnormal MCA-ASPECTS regions was measured automatic measurement).A logistic regression analysis was performed for DWI-ASPECTS,Manual-ASL-ASPECTS and Auto-ASL-ASPECTS,usingchange of number of abnormal MCA-ASPECTS regions as the independent variable and change of NIHSS score as dependent variable.Results: Using linear regression analysis,the CBF value of M2 and M3 regions of the affected hemisphere before treatment was significantly correlated(P<0.05)with the change of prognosis score(difference value of NIHSS score at admission and discharge).When the CBF value of M2 and M3 regions of the affected region increased by 1 unit before treatment,the difference of CBF score at admission and discharge increased by 0.15 and 0.18,respectively.The CBF value of caudate nucleus,internal capsule,lentiform nucleus and perforating branch of middle cerebral artery regions of the affected side was significantly related(p<0.05)to the change of prognosis score after treatment.When the CBF value of caudate nucleus,internal capsule,lentiform nucleus and perforating branch of middle cerebral artery regions increased by 1 unit,the difference of NIHSS score between at admission and discharge increased by 0.26,0.29,0.24 and 0.17,respectively.The difference index of left and right CBF in insular lobe,M2 and M4 region after treatment was significantly related(P<0.05)to the change of prognosis score.When the left and right difference index of CBF in insular lobe,M2 and M4 regions increased by 1 unit,the difference of CBF score at admission and discharge decreased by 0.15,0.17,0.22 respectively.There was no significant correlation between the CBF values of other MCA-ASPECTS regions and the change of prognosis score,and between ADC values of other MCA-ASPECTS regions and the change of prognosis score before and after treatment,the affected side and the control side,and the difference was not statistically significant(P > 0.05).The consistency between the change of the number of abnormal regions and the change of NIHSS score with DWI-ASPECTS,Manual-ASL-ASPECTS and Auto-ASL-ASPECTS was 11.50%,53.8% and 81.20% respectively before and after treatment,and the Chi-square test showed that the Chi-square value was 0.492,0.013 and 5.403,respectively.The correlation coefficients of Cam é r ’sphi was 0.234,0.101 and 0.495,respectively,and the Cam é r’ Fisher’s value was 0.228,0.672 and 0.011,respectively.The change of Auto-ASL-ASPECTS count was moderately correlated with the change of NIHSS score.According to the Logistic regression model of DWI-ASPECTS,Manual-ASL-ASPECTS and Auto-ASL-ASPECTS,the change number of abnormal regions of ASPECTS was taken as an independent variable and the change of NIHSS score was taken as a dependent variable,and the OR value of Auto-ASL-ASPECTS was 15.49(P < 0.05).There was a significant correlation between changed number ofabnormal regions and the change of NIHSS score.The increased number of abnormal Auto-ASL-ASPECTS regions before and after treatment was accompanied by the increase of NIHSS score.Conclusion: There was a correlation between changed number in abnormal regions of MCA-ASPECTS and the change of NIHSS score before and after treatment in patients with ischemic stroke caused by middle cerebral artery stenosis based on the automatic measurement of MCA-ASPECTS area.