Reproducible coronary plaque quantification by multislice computed tomography

Background: The aim of this study was to investigate reproducibility end accuracy of computer-assisted coronary plaque measurements by multislice computed tomography coronary angiography (QMSCT-CA). Methods and Results: Forty-sight patients undergoing MSCT-CA end coronary arteriography for symptomatic coronary artery disease and quantitative intravascular ultrasound (IVUS, QCU) were examined. Two investigators performed the QMSCT-CA twice end e third investigator performed the QCU, all blinded for each other's results. There was no difference found for the matched region of interest (ROI) lengths (QCU 29.4 ± 13 mm vs. QMSCT-CA 29.6 ± 13 mm, P = 0.6; total length = 1,400 mm). The comparison of volumetric measurements showed (lumen QCU 267 ± 139 mm³ vs. mean QMSCT-CA 177 ± 91 mm³, P < 0.001; vessel 454 ± 194 mm³ vs. 398 ± 187 mm ³, P < 0.001; and plaque 189 ± 93 mm³ vs. 222 ± 121 mm³; investigator 1, P = 0.02; and investigator 2, P = 0.07) significant differences. Automated lumen detection was also applied for QMSCT-CA (218 ± 112 mm³, P < 0.001 vs. QCU). The Interinvestigator variability measurements for QMSCT-CA showed no significant differences. Conclusion: QMSCT-CA systematically underestimates absolute coronary lumen- and vessel dimensions when compared with QCU. However, repeated measurements of coronary plaque by QMSCT-CA showed no statistically significant differences, although, the outcome showed a scattered result. Automated lumen detection for QMSCT-CA showed improved results when compered with those of human investigators.