ABSTRACT
INTRODUCTION Selecting an appropriate imaging modality is an essential component of the management of patients with carotid or vertebral disease. The most frequently applied techniques include duplex ultrasound (DUS), computed tomography angiography (CTA), and magnetic resonance angiography (MRA). DUS remains the cornerstone of diagnostics of cervical vascular disease.1 In experienced hands it has excellent sensitivity and specificity for the assessment of stenoses at the level of the proximal internal carotid artery (ICA) and of the distal common carotid artery (CCA). However, for proximal lesions of the CCA and for ostial lesions of the vertebral arteries (VA), the sensitivity and specificity of the DUS decreases.2 In the presence of equivocal DUS findings, CTA and MRA may be performed.3 CTA is fast, easily available, and has excellent sensitivity and specificity for the detection of both cervical and intracranial stenoses. Major limitations of this imaging modality are the use of iodinated contrast media, the radiation exposure, and the artifacts created by dense calcification or bone. MRA can also image accurately the entire cerebrovascular tree at once but has limited specificity for intracranial disease, particularly in severely tortuous vessels.
