Coronary calcium screening using low-dose lung cancer screening: effectiveness of MDCT with retrospective reconstruction

AJR Am J Roentgenol. 2008 Apr;190(4):917-22. doi: 10.2214/AJR.07.2979.

Abstract

Objective: The purpose of our study was to show the usefulness of nongated low-dose chest CT for coronary screening by comparing the results of coronary artery calcium measurement with that of dedicated calcium-scoring CT.

Materials and methods: One hundred twenty-eight consecutive participants (all men; mean age, 52 +/- 7 years) underwent low-dose chest CT and calcium-scoring CT with prospective ECG gating using 40-MDCT. Low-dose chest CT volume data were reconstructed as 25-cm field of view and three slice thicknesses: 1, 2.5, and 5 mm. For each examination, the lesion area, Agatston calcium score, and calcium mass were measured at 90- and 130-H thresholds. All measurements (130-H threshold) from the calcium-scoring CT were used as reference standards. Spearman's correlation test was used to compare the results.

Results: Among the low-dose chest CT examinations, sensitivity was best determined with a 1-mm slice thickness at 130 H and 2.5-mm slice thickness at 90 H. Specificity was best determined with a 5-mm slice thickness at 130 H. Accuracy (90%) was best determined with a 2.5-mm slice thickness at 130 H. Of all protocols, calcium area, score, and mass from a 2.5-mm slice thickness at 130 H correlated best with the reference results (r = 0.89 for all three criteria).

Conclusion: Using a low radiation dose and nongated MDCT, we can detect coronary artery calcium and obtain results comparable to those obtained with dedicated calcium-scoring CT that uses a higher dose and ECG gating.

MeSH terms

  • Adult
  • Aged
  • Body Mass Index
  • Calcinosis / diagnostic imaging*
  • Coronary Artery Disease / diagnostic imaging*
  • Electrocardiography
  • Humans
  • Lung Neoplasms / diagnostic imaging*
  • Male
  • Middle Aged
  • Radiography, Thoracic
  • Regression Analysis
  • Sensitivity and Specificity
  • Tomography, X-Ray Computed / methods*