Topics

Topic

design image
Pancreas

The pancreas is a retroperitoneal gland extending transversely across the posterior abdominal wall at the level of L1–L2, nestled in the curve of the duodenum and extending toward the spleen. It is divided into head, uncinate process, neck, body, and tail. The gland has both exocrine (digestive enzyme secretion via pancreatic ducts) and endocrine (hormone secretion by islets of Langerhans) functions, making it vital for digestion and metabolic regulation. The main pancreatic duct (duct of Wirsung) runs the length of the gland and usually joins the common bile duct to drain at the major duodenal papilla.

Synonyms

  • Pancreatic gland

  • Digestive gland of abdomen

Function

  • Exocrine: secretes digestive enzymes (lipase, amylase, proteases) into the duodenum for nutrient breakdown

  • Endocrine: secretes hormones (insulin, glucagon, somatostatin) for glucose and metabolic regulation

  • Plays a role in neutralizing gastric acid by secreting bicarbonate into the duodenum

Arterial Supply

  • Head and uncinate process: supplied by the superior pancreaticoduodenal artery (from gastroduodenal artery) and inferior pancreaticoduodenal artery (from superior mesenteric artery)

  • Neck, body, and tail: supplied by branches of the splenic artery (pancreatic branches, including the arteria pancreatica magna and caudal pancreatic arteries)

Venous Drainage

  • Pancreatic veins drain into the splenic vein and superior mesenteric vein, both of which contribute to the portal vein

  • Clinical importance: involvement in portal hypertension and pancreatic carcinoma spread

Nerve Supply

  • Parasympathetic: via the vagus nerve (CN X) through the celiac plexus

  • Sympathetic: from the thoracic splanchnic nerves through the celiac and superior mesenteric plexuses

  • Regulates both exocrine secretion and endocrine hormone release

MRI Appearance

T1-weighted images:

  • Normal pancreas is homogeneously high signal intensity, brighter than liver, due to protein- and enzyme-rich parenchyma

  • Masses (adenocarcinoma, focal pancreatitis) usually appear hypointense relative to normal tissue

T2-weighted images:

  • Normal pancreas shows intermediate signal intensity

  • Cysts and fluid collections are hyperintense

  • Inflammation and edema appear as areas of increased signal

STIR (Short Tau Inversion Recovery):

  • Suppresses fat, allowing better visualization of peripancreatic edema, fluid, or inflammation

  • Normal pancreas appears intermediate signal; abnormal lesions appear hyperintense

T1 Post-Contrast (Gadolinium-enhanced):

  • Normal pancreas shows intense, homogeneous arterial phase enhancement due to rich vascularity

  • Tumors typically appear as hypoenhancing masses relative to normal parenchyma

  • Necrosis, cysts, and abscesses may show heterogeneous or rim enhancement

CT Appearance

Non-contrast CT:

  • Pancreas appears as a soft tissue density organ in the retroperitoneum

  • Calcifications may be seen in chronic pancreatitis

  • Limited sensitivity for small tumors or early inflammation

Contrast-enhanced CT (CECT):

  • Normal pancreas shows bright, homogeneous enhancement in the arterial phase

  • Hypoenhancing focal lesions suggest adenocarcinoma or necrosis

  • Hyperenhancing lesions may represent neuroendocrine tumors

  • Best modality for acute pancreatitis (inflammation, fluid collections), trauma, cysts, tumors, and vascular involvement

MRI image

Pancreas anatomy MRI axial image -img-00000-00000

MRI image

Pancreas anatomy MRI coronal image -img-00000-00000

CT image

Pancreas anatomy CT axial image -img-00000-00000