The Correlation Analysis Of Transient Ischemic Attack Of Artery Stenosis And Magnetic Resonance Perfusion Imaging Performance

Background and purpose:Transient ischemic attack (TIA) is common cerebrovascular disease, with the clinically characteristic of repeated onset, transiency, stereotype, recoverability. if it is not treated in time, it can develop into cerebral infarction. The diagnosis of previous TIA based primarily on clinical manifestations, structural imaging (CT or MRI) to check responsibility lesions. In recent years, with the development of imaging, including PET, SPECT, CTP, PWI, Xe-CT, TCD, etc. people gradually pay attention to cerebral perfusion. cerebral perfusion imaging can reflect brain blood flow velocity, brain local microvascular expanding and compensatory enlargement by MTT, TTP .At present internal carotid artery atherosclerosis with narrow or block is a cause of ischemic stroke, the major reason of ischemic stroke is the regional cerebral blood flow decrease. The decrease of regional cerebral blood flow cause the sugar and oxygen decreased of arterial supply blood. Therefore, according to change of cerebral blood flow, this paper discusses the pathogenesis of TIA, proper treatment plan to improve ischemic brain tissue perfusion, prevent stroke.This study aims to explore the relationship between the magnetic resonance perfusion of patients who exist large artery stenosis and TIA and guide clinical treatment.Materials and methods:In March 2009 to March 2010 in our clinic or hospital ward 27 cases of TIA patients (male 25 cases, female in 2 cases, age 35~68 years old, average age 52.37±9.37 years old ) for PWI check. We determined regional of interesting with time to peak (TTP),cerebral blood flow (CBF),cerebral blood volume (CBV) and mean transit time (MTT). According to perfusion performance,They are divided into four type: typeⅠ(collateral circulation formation): TTP or MTT extended, and rCBV or rCBF is fair; typeⅡ(perfusion inadequacy): MTT or TTP significantly prolongs, the rCBV reduce, rCBF significantly reduce. typeⅢ(excessive perfusion): MTT or TTP significantly prolongs with rCBV, rCBF significantly increase; TypeⅣ(reperfusion): MTT shorten or normal, rCBF,CBV increase, normal or mild increase.Results:These cases were not found corresponding new hair infarcts with clinical symptoms in T2WI, T1WI. PWI check shows: abnormal perfusion corresponding to clinical manifestations (20 cases), among them the TTP extend (1 case), TTP, rMTT also extend (12 cases) and rCBF, rCBV normal in 13 cases, rCBF reduced, rCBV normal (4 cases), rCBV reduce, rCBF normal (1 case). rCBV and rCBF also reduce (4 cases). the rCBV and rCBF increase (1 case), four other patients did not find perfusion abnormal manifestation (4 cases). 3 patients found the opposite artery stenosis. TTP, rMTT extend. According to the above, that staging system judgment: TypeⅠ:13 cases; typeⅡ:9 cases; typeⅢ:1case; typeⅣ0 case. 4 cases of is no perfusion abnormal manifestation.Conclusion:(1) PWI is the effective method to judge artery stenosis and TIA microcirculation infusion.(2) TIA and artery stenosis is partly irrelevant, artery stenosis and low perfusion is partly irrelevant.(3) Combining PWI's performance can guide TIA therapy and evaluate prognosis.