Dataset Information

Coronary artery calcium scoring on non-gated, non-contrast chest computed tomography (CT) using wide-detector, high-pitch and fast gantry rotation: comparison with dedicated calcium scoring CT.

ABSTRACT:

Background

Our study assessed the reliability of non-gated, non-contrast chest computed tomography (NCCT) (with high pitch, wide coverage, and fast gantry rotation time, reconstructed at various slice thicknesses), compared with the electrocardiography (ECG)-gated calcium scoring cardiac computed tomography (CaCT), for quantifying coronary artery calcification (CAC).

Methods

Patients aged ≥50 years who required clinical NCCT were prospectively enrolled. All CT scans were performed with 256-detector rows; z-axis coverage, 8 cm; pitch, 1.5; and gantry rotation time, 280 ms (table feed, 42.86 cm/s). NCCT was followed by ECG-gated CaCT. The NCCT images were reconstructed at 0.625-, 1.25-, and 2.5-mm slice intervals. The CAC score was calculated on four sets of CT images with a commercially available software using the Agatston method. The CAC scores were divided into four standard Agatston scoring categories (Agatston scores: 0, 1-100, 101-400, and >400). The inter-observer and inter-technique agreements were evaluated for the CAC scores.

Results

Twenty-six patients (M:F, 14:12; mean age, 66.04±6.97 years) were evaluated. Agatston scores showed near-perfect correlation between CaCT and NCCT for each slice thickness. On Bland-Altman analysis, the mean differences of Agatston scores between CaCT and NCCT (slice thicknesses: 0.625, 1.25, and 2.5 mm) were 37.54, 6.67, and -41.04, respectively. Inter-technique concordance was high for the four Agatston scoring categories with linear-weighted kappa values of 0.599, 0.609, and 0.597 for NCCT (slice thicknesses: 0.625, 1.25, and 2.5 mm, respectively). NCCT with 1.25-mm slice thickness showed the strongest correlation with CaCT.

Conclusions

CAC quantification with NCCT using a wide detector, high pitch, and high temporal resolution scanning modes correlates very highly with ECG-gated CaCT, and 1.25-mm slice thickness NCCT images are more reliable than other NCCT images.

SUBMITTER: Shin JM

PROVIDER: S-EPMC7656362 | biostudies-literature | 2020 Oct

REPOSITORIES: biostudies-literature

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Publications

Coronary artery calcium scoring on non-gated, non-contrast chest computed tomography (CT) using wide-detector, high-pitch and fast gantry rotation: comparison with dedicated calcium scoring CT.

Shin Jae Min JM Kim Tae Hoon TH Kim Ji Young JY Park Chul Hwan CH

Journal of thoracic disease 20201001 10

<h4>Background</h4>Our study assessed the reliability of non-gated, non-contrast chest computed tomography (NCCT) (with high pitch, wide coverage, and fast gantry rotation time, reconstructed at various slice thicknesses), compared with the electrocardiography (ECG)-gated calcium scoring cardiac computed tomography (CaCT), for quantifying coronary artery calcification (CAC).<h4>Methods</h4>Patients aged ≥50 years who required clinical NCCT were prospectively enrolled. All CT scans were performed ...[more]

PMID: 33209410

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Project description:To intra-individually investigate the variation of coronary artery calcium (CAC), aortic valve calcium (AVC), and mitral annular calcium (MAC) scores and the presence of blur artifacts as a function of temporal resolution in patients undergoing non-contrast cardiac CT on a dual-source photon counting detector (PCD) CT. This retrospective, IRB-approved study included 70 patients (30 women, 40 men, mean age 78 ± 9 years) who underwent ECG-gated cardiac non-contrast CT with PCD-CT (gantry rotation time 0.25 s) prior to transcatheter aortic valve replacement. Each scan was reconstructed at a temporal resolution of 66 ms using the dual-source information and at 125 ms using the single-source information. Average heart rate and heart rate variability were calculated from the recorded ECG. CAC, AVC, and MAC were quantified according to the Agatston method on images with both temporal resolutions. Two readers assessed blur artifacts using a 4-point visual grading scale. The influence of average heart rate and heart rate variability on calcium quantification and blur artifacts of the respective structures were analyzed by linear regression analysis. Mean heart rate and heart rate variability during data acquisition were 76 ± 17 beats per minute (bpm) and 4 ± 6 bpm, respectively. CAC scores were smaller on 66 ms (median, 511; interquartile range, 220-978) than on 125 ms reconstructions (538; 203-1050, p < 0.001). Median AVC scores [2809 (2009-3952) versus 3177 (2158-4273)] and median MAC scores [226 (0-1284) versus 251 (0-1574)] were also significantly smaller on 66ms than on 125ms reconstructions (p < 0.001). Reclassification of CAC and AVC risk categories occurred in 4% and 11% of cases, respectively, whereby the risk category was always overestimated on 125ms reconstructions. Image blur artifacts were significantly less on 66ms as opposed to 125 ms reconstructions (p < 0.001). Intra-individual analyses indicate that temporal resolution significantly impacts on calcium scoring with cardiac CT, with CAC, MAC, and AVC being overestimated at lower temporal resolution because of increased motion artifacts eventually leading to an overestimation of patient risk.

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Dataset Information

Coronary artery calcium scoring on non-gated, non-contrast chest computed tomography (CT) using wide-detector, high-pitch and fast gantry rotation: comparison with dedicated calcium scoring CT.

Background

Methods

Results

Conclusions

Publications

Coronary artery calcium scoring on non-gated, non-contrast chest computed tomography (CT) using wide-detector, high-pitch and fast gantry rotation: comparison with dedicated calcium scoring CT.

Similar Datasets

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