Could Ultrasound Elastography Reflect Liver Function?

The purpose of this study was to investigate whether ultrasound elastography reflects liver function reserve relative to liver fibrosis histology. Sixty-five New Zealand rabbits were divided into an experimental group (n = 45) and a control group (n = 20). In the experimental group, liver fibrosis (F1-F4) was induced by subcutaneous injection of carbon tetrachloride. Point shear wave elastography and the indocyanine green (ICG) elimination test were performed for the two groups at 4-wk intervals for 56 wk. The liver stiffness value (LSV) and the ICG retention rate at 15 min (ICGR15) were obtained, and the correlation between them was investigated. The median LSVs of stages F0-F4 were 3.92 kPa (1.91-8.53 kPa), 5.02 kPa (2.39-8.91 kPa), 7.87 kPa (5.21-12.26 kPa), 12.83 kPa (5.92-16.79 kPa) and 16.64 kPa (9.76-29.50 kPa), respectively. The median ICGR15 values of stages F0-F4 were 8.7% (4.8%-15.6%), 10.8% (5.6%-20.3%), 19.2% (12.3%-26.7%), 31.0% (20.9%-41.0%) and 45.6% (22.1%-60.9%). There were significant differences in LSVs and ICGR15 values among the different stages of liver fibrosis (p <0.01). A positive correlation was observed between LSV and ICGR15 (r = 0.7497, p < 0.0001). A strong correlation was observed between liver stiffness and liver function reserve, indicating ultrasound elastography may reflect liver function reserve in different degrees of liver fibrosis.