Validity, Accuracy and Reproducibility of Three-Dimenional Real-Time Echocardiography (RT3DE) for Paediatric Values

Kurzfassung

Purpose Objective of the study was to determine validity, accuracy and reliability of three-dimensional real-time echocardiography (RT3DE) for paediatric values. Material & Methods Using matrix transducers (X7-2, X3-1, Philips), RT3DE was performed on different calibrated phantoms (CIRS 055A, 055 – tissue-mimicking, AIUM 100 mm – non tissue-mimicking). In a systemic variation of parameters on data acquisition and analysis including different 3D workstations (TomTec, QLab), sources of errors were determined and compared to 2D echocardiography. Results Concerning distance measurement, there was a small underestimation of distances (mean relative error: 2D -0.7±1%; 3D -2.7±1%). The orientation of the object had significant effect on distance calculation (vertical: 3.1±1.6% vs. horizontal 0.9±0.6%; p<0.001). Device settings had minor influence. Considering the volume measurements, there was a significant underestimation of the actual volumes by single-plane Simpson: 2D was -8.6±4.3% and 3D was -10.4±0.9%; 3D volumetry using TomTec and QLab was -13.25±1.8%. Concerning data acquisition, gain and compression had significant impact on 2D volume measurements (-3.99±2.2% vs. -13.6±1.7%; p<0.003). Concerning data calculation, different definition of boundary (on vs. within) led to a significant change in results (-17.7±0.9% vs. -24.5±2.3%; p<0.001). There was no statistical significant difference between the 3D workstations used. Conclusion RT3DE is a reliable method for paediatric measurements. Because factors influencing boundary identification (gain, compression, border definition) and transducer orientation have significant impact on distance, area and volume calculation, stanstandardized protocols are mandatory to avoid errors in clinical practice and research.