1. Inter-observer Reproducibility in a Novel Semi-Automated
Coronary Plaque Quantification Software
Michael Fahmy, BS1; Rine Nakanishi, MD1; Suguru Matsumoto, MD1; Anas Alani, MD1; Jeby Abraham, BS1; Sajad Hamal, MSc1; Dong Li, MD,
PhD1; Christopher Dailing, BS1; Ferdinand Flores, BSN BSIT1; Alex Broersen, PhD2; Pieter Kitslaar, MSc2;
Matthew Budoff, MD1.
LA BioMed at Harbor-UCLA Medical Center, Torrance, California, USA1, The Leiden University Medical Center, Amsterdam, Netherland2
Introduction
• Previous studies demonstrated the feasibility to assess
coronary plaque composition from computed
tomography angiography (CCTA).
• However, limited research has been performed to
evaluate the reproducibility of the assessment of total
plaque volume and character between CCTA readers.
• This study was designed to evaluate inter-observer
variability of quantitative plaque assessment.
Methods
• Thirteen patients (9 Men, 61.4 ± 7.7 years) undergoing
64-slice CCTA were evaluated by two experienced
observers.
• Segments with stents were excluded.
• Total plaque volume (TPV), fibrous fatty volume
(FFV), necrotic core volume (NCV), dense calcium
volume (DCV), and non-calcified plaque (NCP) were
analyzed for each segment using a semi-automated
plaque quantification software (Q AngioCT, Medis)
(Figure1).
• Inter-observer variability by two readers was
examined for the plaque measurements.
Table showing coronary artery measurement correlations
between two observers.
Results
Conclusion
• 139 coronary artery segments were closely assessed.
• Among the first and second observers, there were no
significant differences between TPV, NCP, FFV, NCV, and
DCV measurements between the CCTA readers (Table,
Figure2).
Reasonable correlations were observed between two observers.
The semi-automated coronary plaque quantification software
provides a novel, reproducible approach to quantifying
coronary artery non-calcified and calcified plaque.
AVG
+2 SD
-2 SD
-400
-200
0
200
400
600
0 1000 2000 3000
TPV1-TPV2(mm3)
Mean TPV Between Observer 1 and 2 (mm3)
Conflict of Interest: Dr. Matthew Budoff is a consultant for General Electric; the other authors have no conflict of interest.
Observer 1 Observer 2 P value
Total Plaque Volume
(mm3)
1406.93 ± 543.12 1370.78 ± 513.93 0.35
Non-Calcified Plaque
Volume (mm3)
1298.18 ± 450.61 1272.25 ± 482.14 0.62
Fibrous Fatty Volume
(mm3)
332.28 ± 137.20 342.89 ± 173.43 0.75
Necrotic Core Volume
(mm3)
193.11 ± 161.18 174.49 ± 157.63 0.65
Dense Calcium Volume
(mm3)
67.22 ± 115.19 61.38 ± 107.37 0.61
Figure1: The plaque volume measures on CCTA
Figure 2: Bland-Altman Plot for Total Plaque Volume
P=0.35