Small patchy hypodense shadows in the liver are an abnormal manifestation of CT of the liver. There are many reasons for this condition, which may be either an inhomogeneous fatty liver or an occupying lesion in the liver. However, sometimes it is difficult to distinguish them on plain CT, and further enhancement CT and tumor markers are needed to clarify them. For example, heterogeneous fatty liver or focal lipid deposition in the liver does not show enhancement on enhancement CT; while primary liver cancer can show characteristic changes of fast-in and fast-out on enhancement CT; liver hemangioma can show characteristic changes of fast-in and slow-out on enhancement CT; and liver abscess can show characteristic changes of fast-in and slow-out on enhancement CT; Liver abscess in enhanced CT, can appear as abscess wall enhancement, while the low-density necrotic tissue within the abscess does not appear to be enhanced, showing the characteristic change of ring shape. The specific cause and nature of the lesion can be further determined clinically based on the characteristic CT. However, sometimes a liver angiogram, or liver aspiration biopsy is required to finally confirm the diagnosis.