Motion‐Robust Approach for
4D
Cardiac Cine Using
2D
Real‐Time Acquisitions and Slice‐to‐Volume Reconstruction
Ye Tian, Anand A. Joshi, Jon A. Detterich, John C. Wood, Krishna S. Nayak ABSTRACT
Purpose
4D cardiac cine is a powerful tool for comprehensive cardiac function assessment; however, current methods rely on regular breathing and are sensitive to bulk motion and arrhythmia. We aim to develop a 4D cardiac cine approach that requires no patient cooperation and is robust to irregular breathing, bulk motion, and cardiac arrhythmia.
Methods
2D real‐time (RT) spiral bSSFP with synchronized ECG was acquired in 4 cardiac orientations. In each orientation, the 2D slice was “swept” across the heart to provide volume coverage. Retrospectively gated slice‐to‐volume reconstruction (SVR) was then performed to reconstruct 4D cine with 1 mm 3 voxel size and 25 cardiac phases. RT‐SVR and clinical standard breath‐hold short‐axis cine were acquired in 19 subjects, including 4 arrhythmia and 2 myocardial infarction patients. Biventricular volumes were measured, and blood‐myocardium contrast and boundary sharpness scores were compared.
Results
The RT‐SVR approach successfully provided 4D cardiac cine for all subjects. Acquisition time was 8:33 ± 1:01 min and 8:27 ± 2:06 min ( p = 0.85), blood‐myocardium contrast ratio was 2.30 ± 0.58 and 2.38 ± 0.59 ( p = 0.33), boundary sharpness was 1.11 ± 0.46 and 1.18 ± 0.53 ( p = 0.04), for RT‐SVR and breath‐hold cine, respectively. Bi‐ventricular volumes had good agreement, with an ejection fraction bias of −4.02% ( p < 0.05) and −2.30% ( p = 0.10) for left and right ventricles, respectively.
Conclusion
The RT‐SVR approach enables 4D cardiac cine with comparable bi‐ventricular volumes, contrast, sharpness, and acquisition time compared to standard breath‐hold cine while providing additional motion robustness. This approach may be beneficial in patients that are non‐cooperative, children, and those with irregular breathing and/or arrhythmia.