Fig 1.
Mechanism of attenuation imaging with ultrasound.
The signal difference from point A to point B divided by the distance shows the value of attenuation imaging.
Fig 2.
Study flowchart.
Table 1.
Clinical characteristics of the patients (n = 28).
Fig 3.
The distribution of CAP and ATI values according to histologic steatosis grade.
A: ATI was significantly different between S0 and S2, S0 and S3, and S1 and S3 (p < 0.05) with the Kruskal–Wallis test in the post hoc analysis. B: The CAP assessment results were significant between S0 and S2 and S0 and S3, with p < 0.05. The vertical axis is a logarithmic scale. The top and bottom of the boxes are the first and third quartiles, respectively. The length of each box represents the interquartile range, within which is located 50% of the values. The lines through the middle of the boxes represent median values. ATI: attenuation imaging; CAP: controlled attenuation parameter, *: p < 0.05.
Fig 4.
The association between ATI and CAP.
ATI and CAP were significantly correlated (r = 0.8111; p < 0.05).
Fig 5.
Comparing AUROC for ATI and CAP for detecting different grades of liver steatosis.
A: Liver steatosis grade S1 or higher with AUROC values of 0.97 (95% CI: 0.83–1.00) for ATI (blue line) and 0.96 (95% CI: 0.81–0.99) for CAP (green line). B: Liver steatosis grade S2 or higher with AUROC values of 0.99 (95% CI: 0.86–1.00) for ATI and 0.91 (95% CI: 0.74–0.98) for CAP. C: Liver steatosis grade S3 with AUROC values of 0.97 (95% CI: 0.82–1.00) for ATI and 0.88 (95% CI: 0.70–0.97) for CAP. AUROC: area under the receiver operating characteristic curve; ATI: attenuation imaging; CAP: controlled attenuation parameter.
Table 2.
CAP and ATI values for diagnosing liver steatosis.