Advanced Ultrasound in Diagnosis and Therapy (Sep 2019)
Histological Reference for Shear Wave Elastography in Liver Fibrosis: Collagen Quantification and Scoring System
Abstract
Objective: To investigate the significance and value of collagen quantification as an optimized histological standard to evaluate shear wave elastography (SWE) in assessing liver fibrosis. Methods: Liver fibrosis models of rats were created by intraperitoneal injection of thioacetamide over 12 weeks. Liver stiffness was measured with SWE in 96 rats and 16 controls from week 5 to week 12. After removing, three liver specimens were processed for hematoxylin-eosin staining, reticular fiber staining, and picric-sirius red staining, respectively. Liver fibrosis stage (F0-F4) was assessed with the Scheuer scoring system. Collagen was quantified using collagen proportionate area (CPA) with computer-assisted digital image analysis. The Spearman’s rank correlation analysis was performed to determine the correlation between hepatic stiffness measured by SWE, traditional stages and CPA.Results: The mean CPAs in different stages of liver fibrosis were 0.221 ± 0.134, 0.425 ± 0.204, 0.775 ± 0.375, 1.293 ± 0.591, and 2.447 ± 0.891 for F0, F1, F2, F3, and F4, respectively. CPAs showed a strong positive correlation with the traditional scoring system (r = 0.819, P < 0.001). Liver stiffness represented by SWE values exhibited a slightly stronger positive correlation with CPA (r = 0.889, P < 0.001) than with traditional fibrosis staging system (r = 0.836, P < 0.001), with no statistic difference. Conclusion: The accurate and scientific collagen quantification of CPA can be developed as one pathological reference to reliably reflect the diagnostic value of SWE in evaluating liver fibrosis progression.
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