HISTOLOGY AND HISTOPATHOLOGY

Cellular and Molecular Biology

 

An innovative methodology for the automated morphometric and quantitative estimation of liver steatosis

Giuseppa Esterina Liquori1, Giuseppe Calamita2, Davide Cascella3, Maria Mastrodonato1, Piero Portincasa4 and Domenico Ferri1

1Department of Zoology, Laboratory of Histology and Comparative Anatomy, University of Bari, Bari, Italy, 2Department of General and Environmental Physiology, University of Bari, Bari, Italy, 3Department of Electrotechnics and Electronics, Politecnico of Bari, Bari, Italy and 4Department of Internal and Public Medicine, Section of Internal Medicine, University of Bari, Bari, Italy.

Offprint requests to: Prof. Domenico Ferri, Dipartimento di Zoologia, Laboratorio di Istologia e Anatomia comparata, Via Orabona, 4 I-70125 BariI, Italy. e-mail: d.ferri@biologia.uniba.it


Summary. The management of liver steatosis, due to its potential evolution towards severe diseases, requires accurate diagnosis. Fatty infiltration in liver diseases is commonly assessed histologically by semi-quantitative methods, which can be subjective. Automated computerized procedures using commercial software for image analysis have also been recently employed. The aim of the study was to develop an innovative automated computerized procedure to accurately evaluate both the morphometry and degree of lipid accumulation in liver. Fatty infiltration was assessed in paraffin- and resin-embedded samples of steatotic livers from rats undergoing 0, 3, 7, 14, and 30-day choline-deficient diet, and from liver biopsy of a morbidly obese patient undergoing bariatric surgery. Specific software was developed, which works with a morphological operator, in addition to a chromatic one to select lipid droplets. The choline-deficient diet induced steatosis with a gradual shift from micro- to macro-vesicular. In paraffin sections, the macrovesicles-to-microvesicles ratio and the degree of steatosis, when using only the chromatic operator, produced overestimates. Results were consistent in both rat and human samples. An improvement of topographic, morphometric and quantitative estimation of fatty liver infiltration is obtained with our software, working with a morphological operator and using semi-thin sections from resin-embedded samples. This innovative procedure may be applied to human liver samples, offering promising diagnostic and prognostic perspectives. Histol Histopathol 24, 49-60 (2009)

Key words: Liver steatosis, Steatohepatitis, Image analysis, Choline deficient diet, Microscopy