Usefulness of US attenuation imaging for the detection and severity grading of hepatic steatosis in routine abdominal ultrasonography

Abstract

PurposeTo assess the diagnostic performance of ultrasound (US) attenuation imaging (ATI) for diagnosis and grading of hepatic steatosis with comparison to magnetic resonance imaging-proton density fat fraction (MRI-PDFF) using mDIXON-Quant sequence. MethodsTotal 100 patients who underwent abdominal US ATI and MRI-PDFF within one month were included. Subjects were divided into three groups according to MRI-PDFF; Group 1 (no fatty liver), Q < 5.1%; Group 2 (mild fatty liver), 5.1% ≤ Q < 14.1%; and Group 3 (moderate fatty liver), Q ≥ 14.1%. US attenuation coefficients (AC) of enrolled patients were measured and correlated with MRI-PDFF. And their diagnostic performances were assessed. AC, MRI-PDFF, and liver function tests were compared among all groups. ResultsMean AC value of each group was as follows: Group 1 = 0.58 ± 0.11 dB/cm/MHz, Group 2 = 0.68 ± 0.08 dB/cm/MHz, and Group 3 = 0.77 ± 0.06 dB/cm/MHz. Mean AC value of each group of hepatic steatosis showed statistically significant difference (p < 0.001). There was a significant correlation between AC and MRI-PDFF in Pearson correlation (r = 0.751, p < 0.001). The area under the ROC curve (AUROC) of AC was 0.914 with sensitivity of 91.5%, and specificity of 80.0% for detection of mild fatty liver, and 0.935 for detection of moderate fatty liver with sensitivity of 93.3%, and specificity of 87.1%. ConclusionAC using ultrasound ATI showed high diagnostic performance and provided discriminative values for severity grading of fatty liver disease.