Quantification and Characterization of Carotid Calcium with Multi-detector CT-angiography

Abstract

CT-angiography permits the reliable quantification of calcification of carotid plaques. A lower content of calcium in carotid plaques, as well as its distribution in the base of the lesion, was associated with a greater prevalence of neurological symptoms. These parameters may be useful to identify those patients at higher risk of stroke.

The Relation of Carotid Calcium Volume with Carotid Artery Stenosis in Symptomatic Patients

“…Because our results indicate that for symptomatic patients, there is no relation between the degree of stenosis and the severity of stenosis, this finding may support the idea of soft atherosclerotic plaques being more of a risk for stroke than hard calcified plaques, [13][14][15][16] which are associated with plaque stability, and supports the premise that (nonsubendothelial) plaque calcification is associated with plaque stability. This idea is supported by the fact that the occluded arteries had an average calcium volume score of only 0.04 mL.…”

“…A more interesting approach would be to use the calcified plaque volume as a marker for ischemic symptoms. 15 A recent study 17 suggested that extensive calcification is more commonly associated with the asymptomatic side. However, Nandalur et al 18 have shown that the ratio of calcified plaque volume and total plaque volume is significantly inversely associated with the occurrence of symptoms.…”

Atherosclerotic Plaque in the Left Carotid Artery Is More Vulnerable Than in the Right

“…25 In studies that compared carotid atherosclerotic plaques in symptomatic and asymptomatic subjects, calcified plaques were less likely to be symptomatic than noncalcified plaques and asymptomatic patients had a higher calcification content than symptomatic patients. [26][27][28] We found more predominant fibrous tissue and prevalent lipid on the left, which may also reflect higher vulnerability, although their contributions to plaque instability are less conclusive than IPH. Enlargement of the lipid pool may result in the development of a necrotic core, initiating a cascade with fibrous cap erosion or rupture.…”

Analysis of Calcium in Carotid Plaques With Agatston Scores for Appropriate Selection of Surgical Intervention

“…To differentiate calcification from intravascular contrast agent, a threshold of 420 HU was used in line with a previous study. 6 Isotropically interpolated volume scores for calcium were calculated as the products of the numbers of voxels with attenuation Ͼ130 HU and the voxel volumes. Postoperative remained stenoses of carotids were also checked with maximum intensity projection or multiplanar reconstruction images of MDCT by the NASCET method.…”

“…Though carotid atherosclerotic disease often overlaps patient population and risk factors, only limited investigators have used this method with the focus on carotid calcification. 5,6 The aim of the present study was to analyze calcification of individual carotid plaques regarding their quality (hardness) and quantity (volume) by MDCT and determine whether the Agatston calcium score might also be applied as a useful tool for evaluating plaques with calcification as in coronary artery diseases, especially for deciding indications for surgical treatment for carotid stenosis, whether CEA or CAS.…”