Duodenales

Duodenales is a Latin-derived adjective meaning relating to the duodenum. In English medical terminology, the noun duodenum or the adjective duodenal are standard, while duodenales appears in compound terms such as glandulae duodenales (the Brunner’s glands) or papillae duodenales. The term is used primarily in anatomical or histological contexts.

The duodenum is the first section of the small intestine, typically about 25 to 30 centimeters long. It forms a curved, C-shaped portion that extends from the pylorus of the stomach to the jejunum. It is mostly retroperitoneal, with a short intraperitoneal segment near the stomach. The segment is classically divided into four parts: superior, descending, horizontal, and ascending. The descending part contains the major duodenal papilla, where bile and pancreatic duct secretions enter via the hepatopancreatic ampulla, and the minor papilla for the accessory pancreatic duct in some individuals.

Histologically, the duodenum features mucosa with villi and microvilli for absorption, and a submucosal layer that includes the Brunner’s glands (glandulae duodenales) in the proximal part, which secrete alkaline mucus to protect the mucosa from gastric acidity. Plicae circulares are prominent in the proximal sections and diminish distally.

Functionally, the duodenum mixes chyme with bile and pancreatic juice, neutralizes gastric acid, and begins enzymatic digestion of carbohydrates, proteins, and fats. While some nutrient absorption occurs here, most absorption occurs in the jejunum and ileum.

Blood supply comes from the gastroduodenal and superior pancreaticoduodenal arteries, with additional input from the inferior pancreaticoduodenal arteries. Venous drainage routes to the portal system, and innervation is largely parasympathetic via the vagus nerve and sympathetic fibers from the thoracic splanchnic nerves.

Clinically, the duodenum is notable for peptic ulcers, congenital anomalies such as duodenal atresia or annular pancreas, and conditions like diverticula or obstructions affecting drainage of pancreatic secretions.