A 48-year-old woman with severe hepatic cirrhosis due to chronic alcohol use presents with acute hepatic decompensation. Liver biopsy shows extensive hepatocyte ballooning with lipid accumulation, but nuclei remain intact with preserved chromatin pattern. A second biopsy 72 hours later shows hepatocyte collapse, nuclear fragmentation, and extensive apoptotic bodies. Which morphological feature best discriminates reversible from irreversible hepatocyte injury in this case?