Ultrasound findings in spontaneous carotid artery dissection. The value of duplex sonography.
Ultrasound findings in spontaneous carotid artery dissection. The value of duplex sonography.
复制标题
自发性颈动脉夹层的超声检查结果。
作者：
M. Sturzenegger
本文报告六例经血管造影证实的颈内动脉夹层病人的颅外及经颅多普勒及双功超音波表现。颅外多普勒分析显示闭塞，任何水平的颈内动脉均无可记录的信号，或狭窄伴高颈段血流加速。经颅多普勒检查结果显示颈内动脉闭塞或狭窄伴侧支血流穿过Willis环的血流动力学后果，还显示夹层同侧大脑中动脉脉搏波减弱。在双功超声检查中，提示颈内动脉夹层的间接征象是颈动脉分叉和近端颈内动脉段通畅，但无或仅有短的收缩期血流信号。动脉粥样硬化壁变化不存在，这是一个重要的发现，表明非动脉粥样硬化性狭窄或闭塞。诊断的直接征象是颈内动脉球远端管腔逐渐变细，不规则的膜穿过血管管腔，以及显示有血流的真腔和无血流的假腔。虽然脑血管造影仍然被认为是金标准，超声可能成为早期诊断的主要方式。多普勒和双功检查有助于显示血管造影，是随访检查的首选方法。它们清楚地显示了自发再通，颈动脉循环正常化，或者在持续闭塞的情况下，侧支血供改善。序贯检查可能有助于确定抗凝治疗的持续时间。
Extracranial and transcranial Doppler and duplex sonographic findings in six patients with internal carotid artery dissection proven by angiography is reported. Extracranial Doppler analysis showed occlusion without a recordable signal from the internal carotid artery at any level or stenosis with accelerated flow in the high cervical segment. Transcranial Doppler findings demonstrated the hemodynamic consequences of the internal carotid artery occlusion or stenosis with collateral flow across the circle of Willis and also showed the dampened pulse wave of the middle cerebral artery ipsilateral to the dissection. In duplex sonography, the indirect signs indicating internal carotid artery dissection were a patent carotid bifurcation and proximal internal carotid artery segment but with no or only a short systolic flow signal. Atherosclerotic wall changes were absent, an important finding that suggests nonatherosclerotic stenosis or occlusion. Direct signs making the diagnosis likely were a tapering of the internal carotid artery lumen distal to the bulb, an irregular membrane crossing the vessel lumen, and the demonstration of a true lumen with flow and a false one without flow. While cerebral angiography is still considered the gold standard, ultrasound may become the primary modality for early diagnosis. Doppler and duplex examinations help to indicate angiography and are the methods of choice for follow-up investigations. They clearly demonstrate spontaneous recanalization with normalization of carotid circulation or, in case of persistent occlusion, improvement of collateral blood supply. Sequential examinations may prove helpful to determine the duration of anticoagulant treatment.