Non-invasive diagnostic protocol for carotid artery stenosis

Digital Subtraction Angiography (DSA) is now considered the elective diagnostic tool in the evaluation of carotid artery steno-occlusive pathology, although the use of intra-artery catheters implies some latrogenic risk. Aim of the study is to evaluate the possible utilization of a flow-chart based on non-invasive diagnostic tools, such as Ultrasound (US) and Angio-CT in the pathology of neck vessels. We retrospectively evaluated 35 pts with previous Transient Ischaemic Attacks (TIAs) in the carotid artery territory, aged between 38 and 67 years; 21 males, 14 females. The NASCET classification was used to quantify the entity of each carotid stenosis. All patients underwent neck US and Angio-CT; in 15 of them Angio-MRI and DSA were also performed. Angio-CT protocol implies volumetric acquisition from the C6 to the suprasellar region, 3 mm thick slices, 1.5 pitch, 100 ml IV c.m., 3 ml/20 s acquisition time, 1 mm axial image reconstruction, elaboration techniques: SSD, MIP. US and Angio-CT images were comparated with Angio-MRI and DSA findings; according to the present study, axial, SSD, MIP Angio-CT images have the same accuracy as DSA in the evaluation of vessel course and stenosis degree; in the evaluation of vessel course only they are comparable to Angio-MRI; in the quantification of the stenosis their reliability is the same as US. Angio-CT is more sensitive than DSA and MRI in the evaluation of parietal abnormalities. The complementary use of US and Angio-CT techniques gives functional and anatomical information about extra- and intracranial carotid course, making investigation possible also in uncooperative patients with minimal invasitivty.