Avaluation Of The Artery Of Cerebral Wartershed Infarction Combing Carotid Duplex Ultrasound And Transcranial Doppler And DSA

Objective:Ischemic cerebrovascular disease has the characteristics of high incidence,high mortality rates,high disability,and high recurrence rate.Cerebral watershed infarction(CWI) is an important type of ischemic cerebrovascular disease.Study shows that the occurrence and development of CWI is closely related to intracranial and extracranial artery stenosis.The way that fully understand the relationship between cerebral artery stenosis and CWI,early detection of cerebral artery stenosis and to take appropriate intervention measures is very important to timely and effective prevention and treatment of CWI.The most commonly used instruments in vascular screening are carotid ultrasonography and transcranial Doppler(TCD).until now.There are several reports which have evaluated the accuracy of either transcranial Doppler(TCD) estimating the lesions of intracranial artery or carotid color ultrasonography evaluating the lesions of carotid artery in acute stroke setting. Few studies reported the combined ultrasound assessment in acute cerebral ischemia.Digiatl subtraction angiography(DSA) is the "gold standard" in cerebral artery stenosis inspection,and it can define the artery stenosis,the location and extent of stenosis,the formation of collateral circulation,and it can also provide intuitive information for improvement of the diagnosis and the next step of treatment.We appraise artery stenosis in patients with CWI combing carotid color ultrasonography and TCD,analyze the distribution of cerebral artery stenosis,assess the relationship between cerebral artery stenosis and patients with CWI and preliminary study the influence and significance of hypertention for CWI.At last,we compared and verified the result with DSA.Methods:We selected the cerebral watershed infarction patients,including cortical watershed infarction,subcortical watershed infarction and mixed-typed watershed infarction,and excluding CWI by Moyamoya disease,arteriovenous malformation,arteritis,artery dissection,and patients who suffering from artrial fibrillation,polycythemia,and trauma before stroke,heredofamilial stroke,and who accept ultrasound examination unwillingly,and whose temporal window can not be penetrated by ultrasound.All patients undertook neurovascular ultrasound examination within 2 weeks and DSA examination later in stable condition.According to the outcomes of DSA,patients were diveded into three groups:the group of carotid artery stenosis,the group of middle cerebral artery(MCA) stenosis,and the group of intracranial and extracranial artery stenosis.We noted the blood pressur,artery stenosis,and collateral circulation.From the three groups,we chose the patients with unilateral extracranial internal carotid artery(EICA),siphon carotid artery(SCA),or terminal internal carotid artery(TICA) stenosis,excluding those with bilateral EICA and unilateral carotid artery stenosis combined with opposite MCA or anterior cerebral artery(ACA) stenosis.We observed the fact of collateral flow and the velocity of MCA-M1 and ACA-A1 of contralateral side.We also chose the patients with unilateral MCA-M1 stenosis,taking down velocity of ipsilateral ACA-A1 and contralateral MCA-M1.All data was analyzed by SPSS(12.Oversion).Results:1.Location and extent of cerebral artery stenosis:The incidence of extracranial artery stenosis was significantly higher than intracranial artery.This distribution of vascular lesions is inconsistent with the conclusion of recognized ethnic differences,which vascular lesions is mainly the intracranial for Asians and atherosclerotic vascular disease is mainly located in extracranial for caucasian.The stenosis,which is severe,mainly located in the middle cerebral artery branch,siphon carotid artery in intracranial,and it mainly located in carotid artery bifurcation and the beginning of internal carotid artery.2.Blood pressure is not consistent in CWI.The systolic pressure,diastolic pressure and mean arterial pressure of the beginning of internal carotid artery stenosis group are lower than that of MCA stenosis group or TICA stenosis group.3.Carotid color ultrasonography is consistent with DSA in determining the cerebral artery stenosis,but carotid color ultrasonography is more sensitive to plaque.4.Combining carotid color ultrasonography ang TCD is value to determine the collateral circulation.The opening rate of anterior communicating artery(ACOA) is 31.5%in unilateral carotid stenosis and ophthalmic artery(OA) is 25%.The opening of ACOA,OA is of clinical significance.Pial artery can compensate for patients with MCA stenosis.If the ratio of dV_ACA/nV_MCA＞1.15 of pial artery collateral circulation,the ACA may be involve in compensatory.Conclusions:1.Cerebral artery stenosis is an important cause of CWI.2.In general,artery stenosis and "responsibility of artery" of extracranial vascular in our patients with CWI are more than that of intracranial vascular.Intracranial lesions often involve the MCA and extracranial lesions often involve the beginning of internal carotid artery.Watershed infarction cerebral vascular disease is more serious than others.3.We can learn the formation of collateral flow on the foundation of NVUE.After the NVUE assuring the existing of stenosis or occlusion of intercranial and extracranial arteries,the data gotten from TCD can help us to analyze the condition of the formation of collateral flow.Besides detecting the open blood stream frequency spectrum of the primary collateral flow directly,it also can determine the qualitative and the semi-quantitative information of collateral flow referring to the analysis and synthesis of hemodynamics.4.The most collateral circulation in CWI are Willis circle and cerebral pia mater vascular.Severe cerebral artery stenosis caused more collateral circulation.