Hepatic steatosis can be graded as mild, moderate, and severe: 1) mild: mild diffuse increase in liver echogenicity and clear definition of the diaphragm and intrahepatic vessel walls; 2) moderate: mild diffuse increase in liver echogenicity and obscuration of the diaphragm and intrahepatic vessel walls; and 3) severe: marked increase in liver echogenicity leading to nonvisualization of diaphragm and intrahepatic vessel walls [12]. Instead of qualitative assessment of liver and kidney parenchyma, quantitative grading can be done to obtain hepatorenal index. Mancini et al and Webb et al have shown an excellent correlation of mild steatosis quantified on hepatorenal index to fat fraction on MR spectroscopy and liver biopsy, with the area under the curve measuring up to 99.2% and 99.6%, respectively. The hepatorenal index is independent of confounding factors including high body mass index, inflammation, or fibrosis [13,14]. US Abdomen with IV Contrast Cocciolillo et al [15] showed hepatic blood flow derangements in the portal vein and liver parenchyma using contrast-enhanced US (CEUS). The percentage of maximal contrast activity, regional blood volume (cubic centimeters) and regional blood flow (cubic centimeters per second) was reduced in NASH and NAFLD compared with controls. CEUS can be added to conventional US and US shear wave elastography; however, there is no evidence in the current literature to support the use of CEUS in this clinical scenario. US Duplex Doppler Abdomen Duplex Doppler may be added as adjunct to conventional US B-mode images. The normal triphasic flow pattern in right hepatic vein flow may become monophasic following intrahepatic fat deposition or, occasionally, by inflammatory or fibrotic changes [16]. Tarzamni et al [17] found an increase in the arterial resistive index and no change in pulsatility index and portal venous velocity in patients with NAFLD with favorable response to treatment.
Abnormal Liver Function Tests. Hepatic steatosis can be graded as mild, moderate, and severe: 1) mild: mild diffuse increase in liver echogenicity and clear definition of the diaphragm and intrahepatic vessel walls; 2) moderate: mild diffuse increase in liver echogenicity and obscuration of the diaphragm and intrahepatic vessel walls; and 3) severe: marked increase in liver echogenicity leading to nonvisualization of diaphragm and intrahepatic vessel walls [12]. Instead of qualitative assessment of liver and kidney parenchyma, quantitative grading can be done to obtain hepatorenal index. Mancini et al and Webb et al have shown an excellent correlation of mild steatosis quantified on hepatorenal index to fat fraction on MR spectroscopy and liver biopsy, with the area under the curve measuring up to 99.2% and 99.6%, respectively. The hepatorenal index is independent of confounding factors including high body mass index, inflammation, or fibrosis [13,14]. US Abdomen with IV Contrast Cocciolillo et al [15] showed hepatic blood flow derangements in the portal vein and liver parenchyma using contrast-enhanced US (CEUS). The percentage of maximal contrast activity, regional blood volume (cubic centimeters) and regional blood flow (cubic centimeters per second) was reduced in NASH and NAFLD compared with controls. CEUS can be added to conventional US and US shear wave elastography; however, there is no evidence in the current literature to support the use of CEUS in this clinical scenario. US Duplex Doppler Abdomen Duplex Doppler may be added as adjunct to conventional US B-mode images. The normal triphasic flow pattern in right hepatic vein flow may become monophasic following intrahepatic fat deposition or, occasionally, by inflammatory or fibrotic changes [16]. Tarzamni et al [17] found an increase in the arterial resistive index and no change in pulsatility index and portal venous velocity in patients with NAFLD with favorable response to treatment.