Table 2.
Comparison between 3D QCA and IVUS in assessing lumen size
| IVUS | 3D QCA | Difference (95% CI) | Intra-observer variabilitya | Inter-observer variabilitya | |
|---|---|---|---|---|---|
| Positions, n = 519 | |||||
| Short diameter (mm) | 2.51 ± 0.58 | 2.34 ± 0.56 | 0.16 (0.13–0.20)† | 0.022 ± 0.131 | 0.025 ± 0.097 |
| Long diameter (mm) | 3.02 ± 0.62 | 2.63 ± 0.58 | 0.39 (0.36–0.42)† | 0.039 ± 0.162 | 0.042 ± 0.092 |
| Lumen area (mm2) | 6.29 ± 2.77 | 5.08 ± 2.34 | 1.21 (1.07–1.35)† | 0.124 ± 0.534 | 0.134 ± 0.356 |
| Vessels, n = 40 | |||||
| Short diameter (mm) | 2.53 ± 0.39 | 2.35 ± 0.37 | 0.18 (0.10–0.26)† | – | – |
| Long diameter (mm) | 3.05 ± 0.43 | 2.64 ± 0.36 | 0.41 (0.34–0.48)† | – | – |
| Lumen area (mm2) | 6.41 ± 1.92 | 5.12 ± 1.45 | 1.29 (0.95–1.63)† | – | – |
aObserver variability was calculated from 136 positions from the first 10 vessels. CI Confidence interval; † P < 0.001