The Application Of The Whole Brain CT Perfusion Combined With CT Angiography Imaging Techniques In The Evaluation Of Transient Ischemic Attack Patients

Objective:Explore the value of the inspection techniques which the320-row volume CT lowdose the CT perfusion imaging combined with CT angiography in the assessment ofchanges in brain tissue of patients with transient ischemic attack microcirculation.Methods:Application of the320-slice dynamic volume CT, low-dose whole brain CTPimaging of26patients with unilateral middle cerebral artery stenosis or occlusion inpatients with TIA, obtaining MCA area of responsibility of cerebral flow(CBF),cerebralvolume(CBV), mean transit time(MTT), time to peak(TTP)and delay time(DLY)perfusion parameters and dynamic4D-CTA images.Take the mirror measurementtechnique to measured MCA area of responsibility of the affected brain tissue and thecontralateral corresponding parts of the brain tissue,s perfusion indicators specificquantitative values,as well as varying degrees of MCA stenosis or occlusion of the ratioof ipsilateral and contralateral semi-quantitative values;Dynamic4D-CTA imagesobserved the site of vascular stenosis, the degree of stenosis and the collateralcirculation status. T-test was used for the analysis in two sample means andnon-parametric was compared by x2-test.Results:1.26patients successfully completed the whole brain CTP and CTA images,CTscan showed no bleeding，no brain tumors and no massive cerebral infarction. Afterreconstruction and data transfer is completed，clearly observed the ROI perfusionparameters by increase the pseudo-color image contrast.2.26cases of MCA stenosis or occlusion in patients with TIA, MCA mild tomoderate stenosis are17cases (1case of ipsilateral anterior cerebral artery with mildstenosis, two cases of ipsilateral posterior cerebral artery with mild stenosis), MCAsevere stenosis or occlusion of9cases (2cases of ipsilateral posterior cerebral arterywith mild stenosis,1case of ipsilateral anterior cerebral artery with mild stenosis andposterior cerebral artery with mild stenosis). 3.26cases of MCA stenosis or occlusion in patients with TIA,the posteriorcirculation of willis opened14cases(MCA mild to moderate stenosis are6cases, MCAsevere stenosis or occlusion of8cases)，16cases of leptomeningeal anastomotic branchformation(MCA mild to moderate stenosis are8cases, MCA severe stenosis orocclusion of8cases), The former was significantly lower than the latter（P＜0.05，x2=4.35）.4.The ipsilateral CBF, CBV were significantly lower than the contralateral（t=－4.076，p<0.01；t=－4.679，p<0.01）;contralateral MTT, TTP, DLY significantly lowerthan the affected side（t=5.318，p<0.01；t=4.159，p<0.01；t=3.992，p<0.01）; The ratioof the MCA with mild to moderate stenosis group of MTT, TTP, DLY in ipsilateral andcontralateral was significantly lower than the MCA severe stenosis or occlusion group(t=－1.798，p=0.037；t=－1.583，p=0.027；t=－1.536，p=0.005).Conclusion:1. The technology of one-stop CTP combined with CTA imaging has a lowradiation dose, high image quality, scanning time is short and so.4D-DSA shows thedynamic changes in the blood vessels. It reduces the dose of contrast agent application.It has become a new practical imaging method.2.26cases of MCA stenosis or occlusion in patients with TIA, the leptomeningealanastomotic branch formation of MCA severe stenosis or occlusion more than MCAmild to moderate stenosis;In distinction from normal brain and Perfusion abnormalitiesDistrict, TTP and DLY sensitive than the MTT.3.The technology of one-stop CTP combined with CTA imaging reflects braintissue microcirculation which based on visualize the positional relationship of thevascular lesions with abnormal perfusion，assessment of unilateral MCA stenosis orocclusion of cerebral oxygen supply and cerebral blood flow mechanics in patients withTIA,to provide a basis for guiding clinical early treatment of TIA to prevent cerebralinfarction.