Study On The Relationship Between Vertebrobasilar Artery And Posterior Circulation Infarction

Objective:To investigate the correlation between the morphology and hemodynamics of vertebrobasilar artery and posterior circulation infarction(PCI),and to improve the understanding of PCI.Methods:From January 2016 to December 2016,patients aged 18-80 years in the Department of Neurology of Tianjin People’s Hospital were selected as the study subjects.Patients with acute PCI confirmed by MRI were included in the infarction group,and patients without PCI confirmed by MRI were included in the noninfarction group.The basic clinical data,medical history data,head MR imaging data and cervical segmentof vertebral artery(VA)ultrasound data of the patients were collected and analyzed retrospectively as follows:(1)To analyze the difference of clinical data and medical history between infarction group and non-infarction group.(2)To analyze the difference of head MRI between infarction group and noninfarction group.According to the head MRA reconstruction images,the classification of vertebrobasilar artery system(VBS),circle of willis,posterior communicating artery(PCoA)opening and other vascular variation between the two groups were observed and analyzed.Analysis of the differences in the diameter of intracranial segment of VA,vertebral arterydominance(VAD),vertebral artery hypoplasia(VAH)and incidence of moderate to severe stenosis of VA between infarcted and noninfarcted groups based on head MRA data.The differences of the diameter of basilarartery(BA),the degree of deviation and incidence of moderate to severe stenosis of BA between the two groups were statistically analyzed.(3)Based on cervical segmentof VA color Doppler ultrasound data,the differences of diameter,VAD,VAH,resistance index(RI),peak systolic velocity(PSV)and peak blood flow between the two groups were analyzed.Taking the peak blood flow per unit time of one side of VA exceeding 30% of the opposite side as the standard of peak blood flow dominance of VA,the difference of peak blood flow dominance of VA between infarction group and non-infarction group was analyzed.(4)The infarction group was divided into single infarction group and multiple infarction group.The differences of clinical information,MR information and ultrasound information between the two groups were analyzed.SPSS20.0 statistical software was used to analyze the data,test level α = 0.05.Results: 1.A total of 177 subjects were included in this study,including 85 cases in the infarction group and 92 cases in the non-infarction group.The average age of the infarction group(64.2±10.2)was higher than that of the non-infarction group(58.4±8.9),and the male ratio of the infarction group(71.8%)was higher than that of the non-infarction group(40.2%).The difference was statistically significant(P<0.001).The prevalence of diabetes mellitus and hypertension in infarction group(41.2%,63.5%)was higher than that in non-infarction group(18.5%,45.7%)with statistical significance(P<0.05).2.In the infarction group,there were single infarction in 28 cases(32.9%),multiple infarction in 57 cases(67.1%);simple posterior circulation infarction in 36 cases(42.4%),anterior and posterior circulation combined infarction in 49 cases(57.6%).There were 47 cases(55.3%)of cerebral atrophy in infarction group and 9 cases(9.8%)in non-infarction group.3.The diameter of intracranial segment of VA in the infarction group was larger than that in the non-infarction group,and the difference was statistically significant(P<0.011).In the intracranial and cervical segments of VA,there was no significant difference in the incidence of VAD and VAH between infarction group and the noninfarction group.There was no significant difference in the diameter of cervical segment of VA,the diameter of BA and the incidence of BA deviation between the two groups(P?0.05).4.In the infarction group,15 patients(17.6%)suffered from moderate to severe stenosis in the intracranial segment of VA,including 5 patients with moderate to severe stenosis of the bilateral VA and 10 patients with moderate to severe stenosis.of the unilateral VA.There were 6 patients(6.5%)with moderate to severe stenosis of VA in the non-infarction group,all of them were unilateral VA stenosis.The incidence of moderate to severe stenosis of VA in infarction group was significantly higher than that in non-infarction group(P<0.05).Unilateral VA occlusion was found in 3 cases in infarction group and unilateral VA occlusion in 2 cases in non-infarction group.All the 9 patients with moderate to severe stenosis of BA were infarction group.5.In VBS classification,type c accounted for 56.7% in infarction group and 60.7% in non-infarction group.There were 7 cases of type d in the two groups,including 6 cases in infarction group and 1 case in non-infarction group.Type c was the most common in both groups,while type d was more common in infarction group.6.The incidence of complete circle of willis in infarction group(2.4%)was lower than that in non-infarction group(12.0%),and the difference was statistically significant(P=0.014).In the infarction group,PCoA was opened in 30 cases(35.3%),24 cases(28.2%)were unilateral PCoA,6 cases(7.1%)were bilateral PCoA,37 cases(40.2%)were unilateral PCoA,23 cases(25%)were unilateral PCoA and 14 cases(15.2%)were bilateral PCoA.There was no difference in the open proportion of PCoA between the two groups(P=0.500).7.In infarction group,RI increased in 9 cases(10.6%),VA peak blood flow dominantce was found in 57 cases(67.1%),RI increased in 1 case(0.11%),and VA peak blood flow advantage was found in 46 cases(50%).The increase of RI and the incidence of peak blood flow dominantce of VA in infarction group were higher than those in non-infarction group(P<0.05).There was no significant difference in the diameter of cervical segment of VA,PSV and the sum of bilateral VA blood flow between the two groups.8.The proportion of males and the prevalence of hypertension in single infarction group were lower than those in multiple infarction group(P<0.05).The prevalence of hyperlipidemia in single infarction group was higher than that in multiple infarction group(P=0.024).The incidence of moderate to severe stenosis of VA and the increase of RI in single infarction group was lower than that in multiple infarction group(P<0.05).Conclusion: 1.Hypertension,diabetes mellitus and moderate to severe stenosis of intracranial vertebrobasilar artery are risk factors for PCI.2.There are limitations in simply discussing the relationship between vertebrobasilar artery morphology and PCI.It needs to be comprehensively discussed from both morphological and hemodynamic aspects.3.Compared with VAD,the advantage of VA peak blood flow can better predict PCI.