Role Of Doppler Ultrasonography in Diagnosing Early Hepatic Dysfunction in Non-Alcoholic Fatty Liver Disease Patients in Correlation with Elastography

Abstract

Background: Non-alcoholic fatty liver disease (NAFLD) is a common chronic liver disorder with a spectrum ranging from hepatic steatosis to fibrosis and cirrhosis. Early hepatic dysfunction may remain clinically silent. Doppler ultrasonography can provide additional information regarding hepatic and portal haemodynamics, while two-dimensional shear-wave elastography provides quantitative assessment of liver stiffness.

Aim: To evaluate the role of Doppler ultrasonography in detecting early hepatic dysfunction in patients with NAFLD and to assess its relationship with liver stiffness measured by two-dimensional shear-wave elastography.

Methods: This hospital-based observational analytical study was conducted over 18 months in the Department of Radio-Diagnosis and Imaging, Sree Balaji Medical College and Hospital, Chennai. A total of 124 patients aged >20 years with sonographic evidence of fatty liver were included. Patients with significant alcohol consumption, viral hepatitis, other chronic liver diseases, drug-induced steatosis, pregnancy, haemodynamic instability, inability to perform breath-hold or established cirrhosis were excluded. Grayscale ultrasonography was used to grade fatty liver as Grade 1, 2 or 3. Doppler assessment included portal vein diameter, portal vein maximum velocity, portal vein pulsatility index, hepatic vein waveform pattern and hepatic artery resistive index. Three consecutive Doppler measurements were obtained with angle correction maintained below 60°. Two-dimensional shear-wave elastography was performed through an intercostal approach in the right hepatic lobe, with 5–10 valid measurements obtained and the median stiffness value recorded. Correlation and diagnostic performance were assessed statistically, with p<0.05 considered significant.

Results: Among the 124 participants, Grade 1 fatty liver was most common (48.39%), followed by Grade 2 (31.45%) and Grade 3 (20.16%). Age showed a significant association with fatty liver severity (p=0.041), whereas gender did not (p=0.118). With increasing fatty liver severity, liver size and portal vein diameter increased, while portal vein velocity, portal vein pulsatility index and hepatic artery resistive index progressively decreased; all showed statistically significant differences (p=0.001). Hepatic vein waveform abnormalities also increased with severity, with triphasic flow predominating in Grade 1 and monophasic/biphasic patterns becoming more frequent in advanced grades. Abnormal Doppler findings were significantly associated with elastography-defined fibrosis (p=0.001). Doppler ultrasonography demonstrated a sensitivity of 87.10%, specificity of 70.97%, positive predictive value of 75.00%, negative predictive value of 84.62% and overall accuracy of 79.03%.

Conclusion: Doppler ultrasonography demonstrated significant progressive haemodynamic alterations with increasing severity of NAFLD and showed a significant association with elastography-defined fibrosis. Its high sensitivity and accessibility support its role as a useful screening and adjunctive imaging modality for early identification of patients at increased risk of hepatic dysfunction. Doppler assessment should complement, rather than replace, elastography when quantitative assessment of liver stiffness and fibrosis is required.