FIG. 4.

Quantitative comparison of respiration estimation methods among eight clinical patients: (Top) Pearson correlation coefficients between the dynamic 3D self-navigator signal and respiratory bellow signal (blue), and between dynamic 3D self-navigator signal and DC-based self-navigation signal (yellow); (Bottom) Comparison of diaphragm sharpness by the maximum derivative (MD) method. The MD values are normalized by the sharpness value of the dynamic 3D self-navigator reconstruction (reference MD value = 1).