Accuracy of the hepatorenal index with additional standardized acoustic depth assessment for steatotic liver disease diagnosis

Metabolic dysfunction–associated steatotic liver disease (MASLD) is the most common pathology among all chronic liver diseases. In the early stages, steatotic liver disease (SLD) has an asymptomatic clinical course, which makes it difficult to detect. Ultrasound (US) is a safe, noninvasive, first-line method for SLD diagnosis, including determination of the hepatorenal index (HRI). The HRI is a convenient, semiquantitative, noninvasive method for SLD diagnostics. This case‒control observational study aimed to compare the diagnostic accuracy of conventional HRI and HRI with that of additional standardized acoustic depth assessments for SLD using MRI-PDFF as a reference. A total of 161 patients aged 18–67 years were examined. Patients >18 years of age were referred for MRI-PDFF assessment of suspected liver pathology. The only exclusion criterion was an absent or invalid HRI or MRI-PDFF. The quality of the HRI diagnostic model with a baseline (BL) was slightly higher, with an AUROC of 0.917 (p < 0.001), and the sensitivity and specificity were 83.0 % and 95.9 %, respectively. The AUROC for HRI without BL was 0.862 (p < 0.001) with sensitivity and specificity of 84.2 % and 85.1 %, respectively. Bland‒Altman analysis of the comparison of HRIs with and without BL revealed an error of 0.007 (p < 0.05). Our study revealed that it is better to determine the semiquantitative HRI using a reference BL at a standardized uniform depth to preserve acoustic attenuation effects. The advantages of US SLD evaluation for HRI with BL are simplicity of performance and the accuracy of acoustic echogenicity measurements.