Ischemic Stroke And Carotid Endarterectomy

invasive imaging study used to assess carotid stenosis, determines flow information on the basis of the change in frequency of the ultrasound signal reflected from moving red blood cells. B-mode ultrasound, another modality, examines blood vessel anatomy. It can help diagnose ulcerations in 50-95% of patients with carotid artery stenosis and has a higher sensitivity than angiography in the detection of ulceration and intraplaque hemorrhage [25]. Stenotic lesions, however, are difficult to visualize when the carotid bifurcation lies above the mandibular edge, with tortuous carotid arteries, and with a completely occluded carotid artery [25]. Duplex ultrasonography combines B-mode and Doppler ultrasound and helps to visualize vessel anatomy and blood flow velocity at various stages of the cardiac cycle. The study usually includes images of the common carotid artery (CCA), the ICAs and the ECA. High-grade stenosis or occlusion of the ICA is usually associated with a compensatory increase in blood-flow velocity in the ipsilateral ECA and contralateral carotid vessels. Duplex ultrasound, however, is highly technician-dependent and, although common with other non-invasive tests, cannot demonstrate the full extent of the carotid circulation. TCD ultrasonography allows for a non-invasive evaluation of blood velocity and can identify intracranial collateral flow patterns; it also has a high degree of sensitivity in identifying patients with severe ICA disease [26]. A reduction in ultrasound flow velocity in the middle cerebral artery (MCA) distribution can be typically observed distal to an ipsilateral stenotic carotid artery. Small, asymptomatic emboli can also be detected with TCD ultrasonography and can be of help not only in identifying the emboli locus, but also in assessing the response to anticoagulation.

Cure Your Yeast Infection For Good

Cure Your Yeast Infection For Good

The term vaginitis is one that is applied to any inflammation or infection of the vagina, and there are many different conditions that are categorized together under this ‘broad’ heading, including bacterial vaginosis, trichomoniasis and non-infectious vaginitis.

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