Final answer:
The statement is describing the circulatory system, specifically the hepatic portal system in the liver.
Step-by-step explanation:
The statement, 'Centrally is the middle hepatic vein and left hepatic vein. Segments 8, 4a, and 2 (left to right)' is describing the circulatory system. The middle and left hepatic veins are part of the hepatic portal system, which is responsible for supplying blood to the liver. The segments mentioned refer to specific areas of the liver where blood flows from.