Keywords:
Ischaemia / Infarction, Calcifications / Calculi, Arteriosclerosis, Diagnostic procedure, Contrast agent-intravenous, Computer Applications-General, CT-Quantitative, CT-Angiography, CT, Vascular, CNS, Arteries / Aorta
Authors:
V. Rafailidis, I. Chryssogonidis, C. Xerras, T. Tegos, I. NIKOLAOU, A. Charitanti-Kouridou, E. Destanis, A. Kalogera-Fountzila; Thessaloniki/GR
DOI:
10.26044/ecr2019/C-0161
Aims and objectives
Carotid atherosclerotic disease is a well-known cause of transient ischemic attack (TIA) and stroke and its diagnosis and grading primarily relies on imaging,
including virtually every imaging modality from ultrasound (US) to cross-sectional imaging with computed tomography angiography (CTA) or magnetic resonance angiography (MRA).
The degree of internal carotid artery stenosis has been traditionally regarded as the primary determinant for the risk of neurovascular symptoms and the main criterion for defining optimal treatment of patients with carotid disease.
Nevertheless,
the recent literature has made it clear that features of the plaque other than the degree of stenosis also contribute to the plaque’s potential for symptoms,
thus introducing the term “vulnerable plaque” to describe these plaques.
Such features include surface morphology,
intraplaque neovascularization and plaque composition [1-5].
In terms of composition,
atherosclerotic plaques contain different components such as fatty tissue,
calcification,
intraplaque hemorrhage,
and fibrous tissue.
This feature has been found to be associated with the risk for stroke and can be studied with every imaging modality.
CTA has the capability to assess plaque composition using density analysis and measurements in Hounsfield Units (HU).
Based on this method,
plaques can be characterized as fatty when their density is lower than 60 HU,
mixed if density is between 60 and 130 HU and calcified if density is higher than 130 HU.
Studies have shown that fatty plaques are characterized by increased risk for stroke while calcified ones are associated with a lower risk [4,
6,
7,
8].
Nevertheless,
it is known that plaque characterization with CTA can be limited by technical artifacts such as blooming artifact.
As a result,
new technological advances have been introduced into applications commercially available in an attempt to overcome these limitations.
The application used in this study has been previously used in publications and has already provided promising results in the characterization of carotid plaque components [9,
10].
The purpose of this study was tο investigate the correlation of carotid plaque composition as evaluated and quantified with computed tomography angiography (CTA) and the use of a specialized commercially available software with the occurrence of neurologic symptoms in patients with carotid atherosclerotic disease.