Relationship Between Cerebral Vascular Lesions And OCSP Subtypes In Acute Ischemic Stroke

ObjectiveTo determine the characteristic of cerebral vascular lesions by using contrast-enhanced magnetic resonance angiography(CEMRA)and to examine the relationship between cerebral vascular lesions and stroke Bamford subtypes (Oxfordshire Community Stroke Project,OCSP)in acute ischemic stroke.Materials and MethodsWe retrospectively studied the consecutive acute ischemic stroke patients who admitted in the Second Affiliated Hospital,College of Medicine,Zhejiang University,from January 2005 to August 2006.The patients repeatedly admitted were ruled out.Three hundred and fourty patients underwent intracranial and/or neck CEMRA scans.Diagnosis of acute ischemic stroke was in accordance with the diagnostic criteria of cerebrovascular diseases announced in the fourth Chinese meeting of the cerebral vascular disease.Fourty cases was excluded for they was admitted 2 weeks after stroke onset.Thirty-nine cases was ruled out for they had nonatherosclerotic stroke cause:1 with cerebralartery dissection,3 moyamoya disease,2 syphilis,2 neck injuries,1 blood disease,1 lupus erythematosus,29 cardiac source infarction(24 with atrial fibrillation,1 mitral valve calcification,1 dilated cardiomyopathy,1 abnormal cardiac segmental movement,1 sick sinus syndrome,1 rheumatic heart disease).Finally our study included 261 cerebral infarction patients.Their ages were from 23 to 89(61.8±13.08)years old,and 186 of them(71.3%)were men.The patients were divided into six groups according to different CEMRA scanning regions or methods:Group 1,scanning of the intracranial and neck CEMRA;Group 2,scanning of intracranial CEMRA;Group 3, scanning of the neck CEMRA;Group 4,scanning of the intracranial and neck CEMRA at different times,Group 5,all patients with the scanning of intracranial CEMRA;Group 6,all patients with the scanning of the neck CEMRA.Stroke risk factors including gender,age,hypertension,diabetes milletus,hyperlipoidemia, ischemic heart disease,smoking,alcohol drinking and prior stroke or TIA were considered.According to the OCSP classifying method,stroke subtypes were classified as total or partial anterior circulation infarcts(TACI or PACI),posterior circulation infracts(POCI),or lacunar infracts(LACI).Continuous data were describes by mean±standard deviation(SD),while discrete data were processed by X~2 tests.The variables with significant difference between groups were further tested by binary logistic regression.Statistical significance was defined as p＜0.05.ResultsTwo hundred and sixty-one consecutive patients were studied eventually. Among 261 stroke patients 20 patients(7.66%)were classified as TACI,102 patients(39.08%)as PACI,72(27.59%)as POCI,67(25.67%)as LACI.There was no significant difference of risk factors among OCSP subtypes.Totally 140 patients had scanning of both intracranial and neck CEMRA,at one time or at different times, among them,103(73.6%)had vascular lesions 79(56.43%)had intracranial vascular lesions and 62(44.29%)had extracranial vascular lesions),cases of the intracrnial vascular lesions were much more than that of the extracranial vascular lesions(p=0.042).Age≥65 years(OR=2.094,95%CI 1.017-4.315,p=0.045) was an independent predicting factor of the intracranial vascular lesions.Of 206 patients with the scanning of intracranial CEMRA groups,there were more lesions of middle cerebral arteries(MCA)in 9 TACI patients(52.9%)and 38 PACI patients (46.3%)than in patients of other stroke subtypes(p=0.040),and there were more lesions in the intracranial vertebrobasilar arteries(VAi+BA)in 20 POCI patients (32.8%)than in other stroke subtypes(p=0.047).Of 195 patient with the scanning of neck CEMRA,there was no significant difference in the incidence of vascular lesions in extracranial internal carotid artery(ICAe)and extracranial vertebral artery (VAe)among all OCSP subtypes(P＞0.05).Lacunar infarcts(LACI)(46.4%)in the extracranial carotid artery(ICAe)stenosis group was significantly more commonly seen than in the extracranial carotid artery(ICAe)occlusion group (11.5%)(P=0.007);Extracranial vertebral artery(VAe)lesions in the posterior circulation infarct group was significantly higher than in the anterior circulation infarct group(P=0.046);Intracranial vertebrobasilar arteries(VAi+BA)lesions in the posterior circulation infarct group was significantly more commonly seen than in the anterior circulation infarct group(P=0.015),there was no significant difference in the incidence of vascular lesions in extracranial carotid artery(ICAe) and middle cerebral artery(MCA)between the anterior circulation infarct group and the posterior circulation infarct group(P＞0.05).ConclusionPACI was the most common OCSP subtypes.All OCSP subtypes had the same rate of risk factors.Age≥65 year was an independent predictor for intracranial vascular lesions.Total anterior circulation infarcts(TACI)and partial anterior circulation infarcts(PACI)were closely related to MCA lesions.Posterior circulation infracts(POCI)was closely related to intracranial vertebrobasilar artery (VAi+BA)lesions;Incidence of vascular lesions in ICAe and VAe was similar among all OCSP subtypes(TACI,PACI,POCI,LACI).Lacunar infarction(LACI) in the extracranial carotid artery(ICAe)stenosis cases was commonly than in the extracranial carotid artery(ICAe)occlusion cases;Lesions of extracranial vertebral artery(VAe)and intracranial vertebrobasilar artery(VAi+BA)were closely related to the posterior circulation infarct,and the incidences of vascular lesions in the extracranial carotid artery(ICAe)and middle cerebral artery(MCA)were similar in the anterior circulation infarct group and the posterior circulation infarct group.