What are macro and microscopic aspects of hyperemia?

Cutting surface of hyperemic tissue is moist and oozes bloo. In lung (microscopic: blood engorged alveolar capillaries and varying degree of alveolar septa and intra-alveolar hemorrhage, in chronic pulmonary congestion septa thickens and become fibrous, contains hemosiderin-laden macrophages (HF cells) from phagocytosed RBC) In liver (acute congestion we see distention of central vein and sinosiods and maybe centrilobular hepatocyte necrosis, periportal hepatocytes less hypoxia due to oxygenation by hepatic arterioles, only develop fatty alteration. Chronic passive liver congestion we see central reddish brown depressed (cell loss) hepatic lobules, sometimes fatty tanned liver (nutmeg liver) Microscopy shows necrosis of centrilobular hepatocytes, hemorhage and macrophages loaded w/hemisiderin)