European Radiology

, Volume 22, Issue 7, pp 1529–1536 | Cite as

Interobserver agreement for the detection of atherosclerotic plaque in coronary CT angiography: comparison of two low-dose image acquisition protocols with standard retrospectively ECG-gated reconstruction

  • Annika Schuhbäck
  • Mohamed Marwan
  • Sören Gauss
  • Gerd Muschiol
  • Dieter Ropers
  • Christian Schneider
  • Michael Lell
  • Johannes Rixe
  • Christian Hamm
  • Werner G. Daniel
  • Stephan AchenbachEmail author



We compared the interobserver variability concerning the detection of calcified and non-calcified plaque in two different low-dose and standard retrospectively gated protocols for coronary CTA.


150 patients with low heart rates and less than 100 kg body weight were randomised and examined by contrast-enhanced dual-source CT coronary angiography (100 kV, 320 mAs). 50 patients were examined with prospectively ECG-triggered axial acquisition, 50 patients with prospectively ECG-triggered high pitch spiral acquisition, and 50 patients using spiral acquisition with retrospective ECG gating. Two investigators independently analysed the datasets concerning the presence of calcified and non-calcified plaque on a per-segment level.


Mean effective dose was 1.4 ± 0.2 mSv for axial, 0.8 ± 0.07 mSv for high-pitch spiral, and 5.3 ± 2.6 mSV for standard spiral acquisition (P < 0.0001). In axial acquisition, interobserver agreement concerning the presence of atherosclerotic plaque was achieved in 650/749 coronary segments (86.8%). In high-pitch spiral acquisition, agreement was achieved in 664/748 segments (88.8%, n.s.). In standard spiral acquisition, agreement was achieved in 672/738 segments (91.0%, P < 0.0001). Interobserver agreement was significantly higher for calcified than for non-calcified plaque in all data acquisition modes.


Low-dose coronary CT angiography permits the detection of coronary atherosclerotic plaque with good interobserver agreement.

Key Points

Low-dose CT protocols permit coronary plaque detection with good interobserver agreement.

Image noise is a major predictor of interobserver variability.

Interobserver agreement is significantly higher for calcified than for non-calcified plaque.


Coronary CT angiography Atherosclerotic plaque Interobserver agreement Dual-source CT Cardiac 



This study was supported by the German Government, Bundesministerium für Bildung und Forschung (01EX1012B, “Spitzencluster Medical Valley”).


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Copyright information

© European Society of Radiology 2012

Authors and Affiliations

  • Annika Schuhbäck
    • 1
  • Mohamed Marwan
    • 2
  • Sören Gauss
    • 2
  • Gerd Muschiol
    • 2
  • Dieter Ropers
    • 2
  • Christian Schneider
    • 3
  • Michael Lell
    • 4
  • Johannes Rixe
    • 1
  • Christian Hamm
    • 1
  • Werner G. Daniel
    • 2
  • Stephan Achenbach
    • 2
    Email author
  1. 1.Department of CardiologyUniversity of GiessenGiessenGermany
  2. 2.Department of CardiologyUniversity of ErlangenErlangenGermany
  3. 3.Department of RadiologyUniversity of GiessenGiessenGermany
  4. 4.Department of RadiologyUniversity of ErlangenErlangenGermany

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