Model versus non-model based left ventricular volumetry - A matter of imaging modality or quantification software?

Objective: To compare the modalities 3D-echocardiography (RT3DE) and cardiac magnetic resonance as well as semiautomatic non-model-based and model-based quantification software (SWP-MRI and SWT-MRI) regarding accuracy and agreement of left ventricular functional indices. Methods: 9 asymmetrically shaped gel phantoms (range: 20-350ml), 24 healthy children (age=11.4±3.3y) and 11 patients with abnormally shaped left ventricles (22.0±17.0y) were prospectively investigated. 3D-echocardiography was performed using a Vivid 7 ultrasound machine (V3 matrix transducer); postprocessing was done with a model-based analysis strategy (SWT-echo). CMR datasets were obtained using a multi-slice multi-phase steady‑state-free-precision acquisition (TR/TE/flip=2.8msecs/1.4msecs/60°) with a 1.5T MR system. Volume quantification was done using the same model-based software for CMR as well as non model-based software based on the summation of discs method. Agreement of EDV, ESV and EF between SWT-echo, SWP-mri vs. SWT-mri was determined by Bland Altman analysis. Results: Phantom study revealed high accuracy (