Appreciation Of Anterior Circulation Cerebralvascular Atherosclerosis Combining Carotid Duplex Ultrasound And Transcranial Doppler And The Correlated Clinical Significance

Objective: Cerebral vascular atherosclerosis is the primary cause of ischemic cerebralvascular disease nowadays. It is the focus to appraise the level of arterial lesions, and hemodynamic factors precisely, which are attributed to learning the mechanism of acute ischemic atherosclerostic stroke and related to treatment and prognosis. Several reports evaluated the accuracy of either transcranial Doppler (TCD) estimating the lesions of intracranial artery or carotid duplex ultrasound evaluating the lesions of carotid artery in acute stroke setting. Few studies reported the combined ultrasound assessment in acute cerebral ischemia. We appraise cerebralvascular atherosclerosis of acute anterior circulation ischemic stroke patients combining carotid duplex ultrasound and transcranial Doppler (TCD), and discuss the clinical significance of the outcomes.Methods: We selected the acute anterior circulation ischemic stroke patients affirmed by CT or MRI , 50-80 years old, and excluding the patient who suffering from atrial 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. According to the outcomes of CT/MRI and NVUE , patients were divided into three groups: the group of extracranial carotid artery lesions, the group of intracranial artery stenosis, and the group of combined stenosis of extracranial and intracranial artery. To the group of extracranial carotid artery lesions, we noted the echo intension and size of bilateral carotid plaques and examined the level of common carotid artery(CCA) and extracranial internal carotid artery(EICA) stenosis with carotid color Doppler. To the group of intracranial artery stenosis, we examined and noted the stenosis of siphon carotid artery(SCA), terminalinternal carotid artery(TICA), middle cerebral artery segment Ml (MCA-Ml), anterior cerebral artery segment Al(ACA-Al) and noted the echo intension and size of bilateral common carotid artery and extracranial carotid artery plaques meanwhile. To the group of combined stenosis of extracranial and intracranial artery, we only examined and noted the stenosis of CCA/EICA, SCA , and TICA. From the three groups, we chose the patients with unilateral EICA, SCA, or TICA stenosis, excluding those with bilateral EICA and unilateral carotid artery stenosis combined with opposite MCA or ACA stenosis. We observed the fact of collateral flow and the velocity of MCA-Ml and ACA-Al of contralateral side. We also chose the patients with unilateral MCA-Ml stenosis, taking down velocity of ipsilateral ACA-Al and contralateral MCA-Ml. All data was analyzed by SPSS(12.0version).Results: In the group of extracranial carotid artery lesions, the characteristic and size of plaque defined by echo intension with color carotid Doppler is not significantly different between the EICA of CT/MRI positive side and negative side. The positive rate of <50% and 50%-70% stenosis of EICA are also same between bilateral side. The rate of 70-90% and >90% stenosis of CT/MRI positive lateral EICA are higher than the opposite side. In the group of intracranial artery stenosis, the characteristic and size of different echo intension plaque are also the same between bilateral side. The positive rate of stenosis of SCA/TICA and MCA-Ml of CT/MRI positive side is higher than the opposite side, but the positive rate of stenosis of ACA-Al is with no significance between CT/MRI positive and negative side. In the group of combined stenosis of extracranial and intracranial artery, the positive rate of >70% stenosis of EICA and the stenosis of MCA-Ml of CT/MRI positive side are both higher than that of CT/MRI negative side. To the patients with unilateral EICA, SCA, or TICA stenosis, the direct positive rate of opening of AcoAand OA are 26.3% and 25% respectively, and only one patient is found with opening of PcoA. The ratio of nVmAcA/nVmMcA of the group of unilateral carotid artery stenosis is higher than that of control group and further more, the positive rate of nVmACA/nVmMCA>l-25 is also higher than that of control group also. Although the ratio of dVmpcA/nVnipcA is no obvious different between the unilateral carotid artery stenosis group and the control group, the positive rate of dVmPcA/nVmPcA>l-2 of the unilateral carotid artery stenosis group is higher than that of control group. The ratio of dVm.ACA/nVniMCA is also same between the unilateral MCA-Ml stenosis group and control group, but the positive rate of dVmACA/nVniMCA^-O is higher than that of the control group. The ratio of dVmPcA/nVmpcA and the positive rate of dVmpcA/nVmpcA>l-2 is both the same between the unilateral MCA-Ml stenosis group and the control group. The ratio of dVmAcA/nVmMCAof the patients who had no cortical infarction in the group of unilateral MCA-Ml stenosis is higher than that of the control group.Conclusion: (T)The progress of atherosclerosis of bilateral carotid arteries is the same in anyone group. According to the characteristic and size of plaque defined by echo intension with color carotid Doppler, we can not confirm the "responsible" plaque due to artery to artery embolism. ?The definiens of >70% stenosis of CCA/EICA by color carotid Doppler and >50% stenosis of SCA/TICA^ MCA by TCD are well related to ipsilateral ischemic stroke, and the NVUE is value to confirm the "criminal" artery. (3)TCD can help us to analyze collateral flow on the foundation of NVUE, and can also determine the qualitative and the semi -quantitative information of collateral flow.