Diagnostic Imaging of Carotid Artery

In the study of carotid arteries, the different imaging techniques allow to analyze various diseases like stenoses, aneurysms, thromboses, dissections, diseases caused by athero sclerotic plaques or congenital abnormalities. The diagnostic modalities that are used to image the carotid artery diseases are digital subtraction angiography (DSA), duplex ultrasound (DUS), computed tomography angiography (CTA), and magnetic resonance angiography (MRA). The goal of the diagnostic imaging is to provide screening and to detect diseases at its earliest and most treatable stage. As initial screening study, the radi - ologists recommend DUS. It is a safe and painless way to produce pictures of the inside of the body using sound waves. It assesses blood flow in the carotid arteries, measures the speed of the blood flow, and estimates the diameter of a blood vessel and degree of obstruction. Digital subtraction angiography (DSA) has assumed a major role in the evaluation of occlusive cerebrovascular disease. While digital subtraction angiography (DSA) is still considered the gold standard, it has increasingly been replaced by computed tomography angiography (CTA) or magnetic resonance angiography (MRA) during the last years. Modern imaging studies like CTA and MRI allow to obtain three-dimensional reconstruction of anatomic structures and pathological abnormalities. Computed tomog raphy angiography (CTA) of carotid arteries is a standardized procedure with excellent image quality but related with high radiation exposure. The rapid technical evolution in hardware and software allows even smaller imaging centers to perform high-quality ves - sel imaging. During the last decade, CTA came up with substantial progress in terms of accuracy in stenosis and aneurysm detection. Magnetic resonance angiography (MRA) is increasingly used as a noninvasive method to assess carotid arteries. Diseases like carotid artery dissections could be detected by using MRA or CTA. occlusion About 190 patients with, or without, proximal extra- and intracranial occlusions were by TCD. The obtained data were compared with those from DSA and MRA. Angiographic examination showed occlusion in 48 patients. The TCD showed Doppler signals unusual for the middle cerebral artery in 66.7%; reverse blood flow through the oph thalmic arteries in 70.6%; and blood flow through the anterior communicating artery in 78.6% and through the posterior communicating artery in 71.4%. The study showed that transcranial Doppler sonography data for large artery occlusions can be used to extend complex diagnosis and improve prognostic value for noninvasive screening in stroke patients The diagnostic capabilities of digital intra-arterial angiography and transcranial sonography were compared in 48 patients with acute ischemia in the artery basin on the fourth hour after onset of symptoms. Data from the exam showed correla with angiographic with clinical suspicion of acute vertebral artery occlusion. Criteria for inclusion of the patients were the clinical manifestations of sudden worsening of consciousness, dizziness, diplopia, dysarthria, oculomotor nerve lesions, and lesions of other cranial nerves or bilateral symptoms. Three patients were in coma. The diagnostic capabilities of CTA, DUS, and DSA, used for these patients, were compared. CTA revealed a complete occlusion of the basilar artery in nine patients and an incomplete occlu sion in two of them. Due to severe vertebral artery calcification, one patient could not be examined. Doppler sonography was performed in 7 of 19 patients, with clear evidence of vertebral artery occlusion in 3 of them. In the remaining patients, the data were uncertain and two were false-negative, which was proved by CTA and DSA exams. In addition, CTA on the exact place of basilar artery occlusion. These data allowed for intra-arterial thrombolysis to be used in five patients. In conclusion, CTA more informa tive than DUS in assessing the patency of the basilar artery in patients with acute ischemia, especially in the distal artery occlusion. The study emphasizes the advantages of the combina tion of methods, used for the diagnosis of basilar artery occlusion