To correlate ultrasound imaging and histology in hepatic steatosis.
Material and method
Liver biopsy slides of cases in which hepatic steatosis were classified as mild, moderate and severe was evaluated, determining the number of fat cells per microscopic field from the histological sections. The number of fat cells per field was correlated with the degree of hepatic steatosis suggested on ultrasound examination.
Mean number of fat cells per microscopic field was 50 in mild steatosis, 85 in moderate steatosis, and greater than 150 fat cells in severe steatosis. A significant correlation was observed between echogenicity and the number of fat cells, i.e. the more fat cell the higher the proportion of sound waves incident perpendicularly, being reflected back to the transducer (hyperechogenicity), while in normal liver tissue there is a greater dispersion of the sound wave (hypoechogenicity).
The main interface of echo reflection in steatotic liver tissue is the boundary between the normal hepatocyte and fatty infiltration.