Segment S8 of the liver is the upper segment of the right anterior lobe, between the middle hepatic vein and the right hepatic vein, close to the diaphragm, in a high position, with the upper border roughly leveling the 5th to 6th ribs. The Couinaud segmentation method is generally used in clinical practice to divide the liver into eight segments according to the distribution of the hepatic vein and portal vein in the liver. Briefly, they are divided into left external, left internal, right anterior, and right posterior, except for the left internal, which is no longer divided, and each zone is further divided into two segments; the caudate lobe is no longer subdivided, and each hepatic segment is crowned with a Roman numeral to indicate it (Ⅰ to Ⅷ), with S1 being the caudate lobe, S2 being the upper segment of the left external lobe, S3 being the lower segment of the left external lobe, S4 being the left internal lobe, S5 being the lower segment of the right anterior lobe, S6 being the lower segment of the right posterior lobe, S7 being the upper segment of the right posterior lobe, and S8 being the right anterior upper segment of the right anterior lobe. Segmentation is used to better pinpoint the location of the lesion, and each liver segment needs to be differentiated on imaging. If abnormalities are detected, it is recommended to follow the doctor’s instructions for the next step in the examination and treatment.