The head of pancreas is the widest and foremost part of the pancreas, cradled in the bend of the duodenum, which loops around the head. Comprising roughly 20 percent of the pancreas, the head of pancreas contains the ampulla of Vater, the intersection of ducts where the pancreatic duct, which runs the entire length of the pancreas, meets the bile duct, which carries digestive fluids from the gallbladder to the duodenum. Located just behind the small intestines and the stomach, that pancreas is a gland that aids in digestion and provides the body with insulin. In addition to the head of pancreas, the gland contains four other major parts: the neck of pancreas, body, tail and a backward bending section right behind the head, known as the uncinate process.
Positioned on the rear right side of the human abdomen near the third vertebrae of the spine, the head of pancreas is roughly 1.5 inches (4 cm) in width, but can be as wide as 2.4 inches (6 cm) in some individuals. The head is home to two important blood vessels: the superior mesenteric vein and the superior mesenteric artery. Such vessels are responsible for circulating blood to the liver and intestines.
Enzymes produced by the head of pancreas make digestion more efficient by metabolizing lipids, carbohydrates and proteins at the chemical level so that the body can absorb a maximum amount of minerals and vitamins. A malfunctioning head of pancreas can lead, therefore, to poor nutrient absorption and malnutrition. It can also result in diarrhea or a poor neutralization of acids in the stomach. In addition, insulin produced by the head of pancreas aids in maintaining proper blood sugar levels in the body. While the entire gland manufactures insulin, the produces an enormous portion of this necessary hormone — so much so that if the head is harmed or removed, a person may be at risk for diabetes.
Many diseases, unfortunately, can harm the head of pancreas, impairing its digestive and insulin-producing functions. Cancer can occasionally afflict the head, triggering symptoms such as jaundice, stomach pain, and unintentional weight loss. When this happens, the head of pancreas swells and blocks the bile duct. To cure the malignancy and restore the flow of bile, surgeons usually remove the entire head of pancreas in a procedure called the Whipple Operation. Infections, abscesses, and cysts can also develop within the head section of the pancreas, as can mumps.