J Cardiovasc Comput Tomogr. 2016 Mar-Apr;10(2):114-20. doi: 10.1016/j.jcct.2015.11.003. Epub 2015 Dec 2.
Øvrehus KA1, Schuhbaeck A2, Marwan M2, Achenbach S2, Nørgaard BL3, Bøtker HE3, Dey D3.
INTRODUCTION:
Coronary computed tomographic angiography (CTA) can characterize coronary atherosclerotic plaque components as calcified and non-calcified. Quantitative measurements of coronary plaque burden by coronary CTA may play a role in serial studies to determine disease progression or response to medical therapies. The reproducibility from repeated assessment of such quantitative measurements from low-radiation dose coronary CTA has not been previously assessed.
PURPOSE:
To evaluate the interscan, interobserver and intraobserver reproducibility for coronary plaque volume assessment using semi-automatic plaque analyses algorithm in low radiation dose coronary CTA.
METHODS:
In 50 consecutive patients undergoing two 128-slice dual source CT scans within 12 days with a mean radiation dose of 0.7 mSv per coronary CTA, the interscan, interobserver and intraobserver reproducibility of coronary plaque assessment using validated software (AutoPlaq) were evaluated. RESULTS:
Interscan, interobserver and intraobserver agreement for non-calcified and calcified plaque volumes were excellent (Spearman rho 0.87-0.99). Interscan mean percentage difference in non-calcified and calcified plaque volumes were 0.1% (p = 0.8) and 1.9% (p = 0.19) with limits of agreement of ±11% and ±48.5%; per inter- and intraobserver mean percentage differences were 0.1% (p = 0.25) and 0.3% (p = 0.001), and 0.3% (p = 0.33) and 0.4% (p = 0.59) with limits of agreement of ±7% and ±32.9%, and ±6.6% and ±32.1%, respectively.
CONCLUSION:
A semi-automatic plaque assessment algorithm in repeated low radiation dose coronary CTA allows for high reproducibility of coronary plaque characterization and quantification measures.