A Comparison of Hyperelastic Warping of PET Images with Tagged MRI for the Analysis of Cardiac Deformation

Table 2

Sensitivity results for Heart 2. The results of Heart 2 analyses show similar trends to those seen in the Heart 1 analyses. An SNR level of 0.5 (bold) caused severe degradation of the registration results also with large increases in %RMSE and a reduction of the 𝑅² values.

	Cir. strain		Radial strain
	%RMSE	𝑅^2	%RMSE	𝑅^2
Validation study	0.093	0.830	0.113	0.780
SNR 8	0.095	0.824	0.113	0.773
SNR 4	0.099	0.820	0.113	0.773
SNR 1	0.099	0.821	0.113	0.804
SNR 0.5	0.329	0.094	0.412	0.080
SNR 0.1	0.114	0.790	0.124	0.770
Reduction in fiber angle (+5%)	0.092	0.830	0.110	0.780
Increase in fiber angle (−5%)	0.092	0.840	0.100	0.790
10% reduction in intensity	0.092	0.850	0.100	0.800
20% reduction in intensity	0.095	0.840	0.100	0.790
40% reduction in intensity	0.096	0.830	0.110	0.790
No active contraction	0.156	0.638	0.214	0.612