Image quality and diagnostic performance of free-breathing diffusion-weighted imaging for hepatocellular carcinoma

Table 3 Results of qualitative assessment of the free-breathing diffusion-weighted imaging and respiratory-triggering-diffusion-weighted imaging results

	Sharpness of the liver contour		Distortion		Chemical shift artifacts
	FB-DWI	RT-DWI	FB-DWI	RT-DWI	FB-DWI	RT-DWI
Observer 1	3.08 ± 0.81	2.33 ± 0.65a	2.94 ± 0.50	2.81 ± 0.56a	3.38 ± 0.60	2.92 ± 0.59a
Observer 2	2.98 ± 0.73	2.37 ± 0.74a	2.71 ± 0.70	2.25 ± 0.74a	3.15 ± 1.07	2.21 ± 0.85a
Observer 3	3.54 ± 0.75	2.75 ± 0.81a	3.27 ± 0.53	2.96 ± 0.71a	3.21 ± 0.85	2.77 ± 1.08a

Data are the average ± SD.

^aP < 0.05 by the Wilcoxon signed-rank test. FB-DWI: Diffusion-weighted imaging with modified MR parameter settings for image improvement by referring to the literature[18]; RT-DWI: Navigator-echo-based, real-time respiratory-gating and respiratory-triggered diffusion-weighted imaging without modified MR parameter settings.