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Quantification of abdominal aortic calcification: Inherent measurement errors in current computed tomography imaging.

ABSTRACT: Quantification software for coronary calcification is often used to measure abdominal aortic calcification on computed tomography (CT) images. However, there is no evidence substantiating the reliability and accuracy of these tools in this setting. Differences in coronary and abdominal CT acquisition and presence of intravascular contrast may affect the results of these tools. Therefore, this study investigates the effects of CT acquisition parameters and iodine contrast on automated quantification of aortic calcium on CT.Calcium scores, provided in volume and mass, were assessed by automated calcium quantification software on CT scans. First, differences in calcium scores between the abdominal and coronary CT scanning protocols were assessed by imaging a thorax phantom containing calcifications of 9 metrical variations. Second, aortic calcification was quantified in 50 unenhanced and contrast-enhanced clinical abdominal CT scans at a calcification threshold of 299 Hounsfield Units (HU). Also, the lowest possible HU threshold for calcifications was calculated per individual patient and compared to a 130 HU threshold between contrast-enhanced and unenhanced CT images, respectively.No significant differences in volume and mass scores between the abdominal and the coronary CT protocol were found. However, volume and mass of all calcifications were overestimated compared to the physical volume and mass (volume range: 0-649%; mass range: 0-2619%). In comparing unenhanced versus contrast-enhanced CT images showed significant volume differences for both thresholds, as well as for mass differences for the 130 vs patient-specific threshold (230 ± 22.6 HU).Calcification scoring on CT angiography tends to grossly overestimate volume and mass suggesting a low accuracy and reliability. These are reduced further by interference of intravascular contrast. Future studies applying calcium quantification tools on CT angiography imaging should acknowledge these issues and apply corrective measures to ensure the validity of their outcomes.

SUBMITTER: Buijs RVC

PROVIDER: S-EPMC5831389 | biostudies-literature | 2018

REPOSITORIES: biostudies-literature

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Quantification of abdominal aortic calcification: Inherent measurement errors in current computed tomography imaging.

Buijs Ruben V C RVC Leemans Eva L EL Greuter Marcel M Tielliu Ignace F J IFJ Zeebregts Clark J CJ Willems Tineke P TP

PloS one 20180228 2

<h4>Objective</h4>Quantification software for coronary calcification is often used to measure abdominal aortic calcification on computed tomography (CT) images. However, there is no evidence substantiating the reliability and accuracy of these tools in this setting. Differences in coronary and abdominal CT acquisition and presence of intravascular contrast may affect the results of these tools. Therefore, this study investigates the effects of CT acquisition parameters and iodine contrast on aut ...[more]

PMID: 29489868

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Dataset Information

Quantification of abdominal aortic calcification: Inherent measurement errors in current computed tomography imaging.

Publications

Quantification of abdominal aortic calcification: Inherent measurement errors in current computed tomography imaging.

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