Application Value Of High-resolution Vessel Wall Imaging Combined With Synthetic MRI In The Study Of Atherosclerosis

Objective To compare the consistency of 3.0T high-resolution vessel wall imaging(HR-VWI)and computed tomographic angiography(CTA)in the measurement of carotid atherosclerosis(AS)stenosis.To explore the clinical value HR-VWI combined with synthetic MRI in carotid atherosclerotic plaque.Methods A total of 30 patients with carotid atherosclerotic stenosis and carotid atherosclerotic plaque confirmed by CTA in our hospital from February 2021 to February 2022 were collected as the research objects.CTA,HR-VWI conventional multi contrast sequence,cube sequence and magic sequence were performed on 56 carotid arteries of 30 patients.CTA and CUBE sequences were measured to show the stenosis rate carotid atherosclerosis,and their consistency was compared.The morphology and main components of carotid atherosclerotic plaque were analyzed by magnetic resonance vulnerable plaque diagnostics(MR-VPD).The quantitative parameters of standardized tube wall index(NWI),lipid core(IRNC),calcification(Ca),intra plaque hemorrhage(IPH),loose matrix(LM)and fiber cap(FC)were obtained,and statistical analysis was carried out.According to the improved AHA(American Heart Association)plaque classification for MRI,as plaque was divided into vulnerable plaque group and stable plaque group.Through the post-processing of magic sequence images,the conventional T2 and T2 mapping maps were obtained,and the T1/T2 value of the plaque in the narrowest lumen was measured.The difference of T1/T2 value between the two groups was compared by independent sample t-test.The optimal threshold and diagnostic efficacy of T1/T2 value in predicting cerebrovascular symptoms were evaluated by receiver operating characteristic(ROC)curve.Results1.The results measured by research A showed that the Bland Altman difference map and ratio map showed that the average 10.71%(6/56)points were outside the 95% consistency limit.The difference amplitude and ratio amplitude were acceptable clinic,and the consistency of carotid stenosis rate measured by HR-VWI and CTA was high.Researcher B’s measurement results showed that the Bland Altman difference diagram and ratio diagram showed that the average 8.92%(5/56)points were outside the 95% consistency limit,the difference amplitude and ratio amplitude were acceptable in clinic.HR-VWI and CTA have high consistency in measuring the rate of carotid stenosis.The measurement results of researcher A and researcher B had high consistency.The intraclass correlation coefficient(ICC)and 95% consistency limit.HR-VWI=0.904(0.841,0.942),CTA=0.925(0.876,0.956).2.The T1 values of vulnerable plaque group and stable plaque group were 1536.53 ±586.41 ms and 2226.21 ± 388.09 ms respectively,and the T2 values were 136.25 ± 16.46 ms and 60.86 ± 13.76 ms respectively(P < 0.001);ROC curve analysis showed that the T1 / T2 values of plaque were 1732.81 and 88 ms respectively,which was the best diagnostic threshold for predicting cerebrovascular symptoms,and its sensitivity and specificity were63.3%,73.3% and 83.3%,80.0% respectively.Conclusion1.There is no significant between the measurement results of HR-VWI and CTA in the stenosis atherosclerosis.Under certain circumstances,HR-VWI can effectively replace CTA in clinical application.2.The T1/T2 value of carotid atherosclerotic plaque was correlated with cerebrovascular symptoms.The T1 value of vulnerable plaque group was significantly higher than that of stable plaque group.The T2 value of vulnerable plaque group was significantly higher than that of stable plaque group.