TABLE 2.

Comparison with others.

		Synthetic PET		Synthetic MRI
		PSNR	SSIM	PSNR	SSIM
Pan et al., 2020	HGAN	30.24	0.6945	26.07	0.6683
Pan et al., 2019	FGAN	29.62	0.6817	25.10	0.6404
Hu et al., 2019	Adversarial U-Net (2D slice)	25.13	−	−	−
Pan et al., 2018	3D-cGAN	24.49	−	−	−
The proposed method (ROI)	RevGAN	29.34	0.8034	29.81	0.9389
The proposed method (Full Data)	RevGAN	29.42	0.8176	24.97	0.6746

The quality of the reconstructed image. Results of image synthesis achieved by different methods. Just as a reference, because the selected data and data preprocessing are different. Bold values mean the best value in the comparative experiment.