Sinus dilatation

Pathogenesis of hepatic venous occlusive disease: Sinus dilatation occurs in both the acute and subacute phases. In the acute phase, the liver is enlarged and the surface is smooth. Lymphatic dilatation and signs of "crying" can be seen. Under the light microscope, the intima of the central and sublobular veins were significantly swollen, the lumen was narrowed or occluded, blood flow was blocked, and the sinusoids were significantly dilated and congested, accompanied by turbid swelling, degeneration and necrosis of liver cells to varying degrees. Hepatocytes disappeared in the severe necrosis area, reticular fibrous scaffolds remained, red blood cells infiltrated into the liver sinus and Disse's space, showing typical hemorrhagic necrosis changes. In the subacute stage, the surface of the liver showed a reticular regional contraction, and the central and sublobular vein endothelial cells proliferated and thickened, forming fibrosis and stenosis and occlusion of the lumen. Sinus dilation, congestion, and hemorrhagic hepatocyte necrosis may still occur during this period, fibrosis in the central vein, and no pseudolobules have formed.