Preliminary study of early histomorphometric changes in hepatic steatosis

The first endpoint of this study was to find new markers that document the progression of hepatic steatosis through quantitative histomorphometric analysis in the absence of hemodynamic changes. The second endpoint was to start building a mathematical database to help to achieve a score in the future. For this study we enrolled 130 random patients, including 10 with normal histology despite suspected disease, 70 positive for steatosis, 20 affected by nonalcoholic steato hepatitis, and 30 with hepatitis virus C or B-related cirrhosis. One hundred thirty images were analyzed for a total of 1,320 sinusoids. Each image was processed with a custom program written with the use of the Vision toolbox of the Labview platform, following a semiautomated procedure. The mean sinusoidal areas (SAs) and percentage fractions of parenchymal area occupied by sinusoids (SA/PA) were subdivided into 3 groups. Finally, we analyzed the form of sinusoids, approximating them to an ellipse, to be able to define the relationship between the 2 axes with the aim of proposing a parameter, "local hydraulic resistance" (LHR), that was proportional to the resistance to blood flow within the bounds of the histologic specimen. Among the images, we observed a difference in the size of SAs among the 3 groups of patients, namely, normal, steatotic of different stages, and cirrhotic patients. In fact, there was evidence of a reducted SA when steatosis was <30%, with an average value of 0.0032 mm(2), patients with steatosis of 30%-50% showed an average SA of 0.0024 mm(2), and there was a further reduction among subjects with steatosis grades >50% (mean 0.0017 mm(2)). The LHR value showed that the morphometric parameter SA/PA could be quantitatively interpreted also as a functional impairment relative to the increased resistance opposing blood flow in pathologic conditions.