Volumetric characterization of human coronary calcification by frequency-domain optical coherence tomography

Circ J. 2013;77(9):2334-40. doi: 10.1253/circj.cj-12-1458. Epub 2013 Jun 19.


Background: Coronary artery calcification (CAC) presents unique challenges for percutaneous coronary intervention. Calcium appears as a signal-poor region with well-defined borders by frequency-domain optical coherence tomography (FD-OCT). The objective of this study was to demonstrate the accuracy of intravascular FD-OCT to determine the distribution of CAC.

Methods and results: Cadaveric coronary arteries were imaged using FD-OCT at 100-μm frame interval. Arteries were subsequently frozen, sectioned and imaged at 20-μm intervals using the Case Cryo-Imaging automated system(TM). Full volumetric co-registration between FD-OCT and cryo-imaging was performed. Calcium area, calcium-lumen distance (depth) and calcium angle were traced on every cross-section; volumetric quantification was performed offline. In total, 30 left anterior descending arteries were imaged: 13 vessels had a total of 55 plaques with calcification by cryo-imaging; FD-OCT identified 47 (85%) of these plaques. A total of 1,285 cryo-images were analyzed and compared with corresponding co-registered 257 FD-OCT images. Calcium distribution, represented by the mean depth and the mean calcium angle, was similar, with excellent correlation between FD-OCT and cryo-imaging respectively (mean depth: 0.25±0.09 vs. 0.26±0.12mm, P=0.742; R=0.90), (mean angle: 35.33±21.86° vs. 39.68±26.61°, P=0.207; R=0.90). Calcium volume was underestimated in large calcifications (3.11±2.14 vs. 4.58±3.39mm(3), P=0.001) in OCT vs. cryo respectively.

Conclusions: Intravascular FD-OCT can accurately characterize CAC distribution. OCT can quantify absolute calcium volume, but may underestimate calcium burden in large plaques with poorly defined abluminal borders.

Publication types

  • Clinical Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Calcium*
  • Coronary Artery Disease* / metabolism
  • Coronary Artery Disease* / pathology
  • Coronary Vessels* / metabolism
  • Coronary Vessels* / pathology
  • Female
  • Humans
  • Male
  • Middle Aged
  • Plaque, Atherosclerotic* / metabolism
  • Plaque, Atherosclerotic* / pathology
  • Tomography, Optical Coherence*
  • Vascular Calcification* / metabolism
  • Vascular Calcification* / pathology


  • Calcium