Pancreatic head cancer refers to a tumor in the head of the pancreas, which is a malignant tumor. In the arterial stage, normal pancreatic tissues are obviously enhanced during intensive CT, but pancreatic head cancer is a lack of blood supply tissue, so enhancement is not obvious. The comparison between the two can confirm the diagnosis of pancreatic head cancer and determine the size of pancreatic head cancer and whether it has invaded blood vessels, such as whether it encircles the superior mesenteric artery or whether it invades the superior mesenteric vein and portal vein, which can guide the patient during surgery. If the tumor encircles the superior mesenteric artery more than 180°, the surgery is very difficult and is not recommended.