Annular pancreas: An abnormal ring of pancreas that encircles the duodenum and often causes intestinal obstruction.
Nausea and vomiting are the usual symptoms and reflect the intestinal obstruction. Complete obstruction is usually evident in the newborn period. Partial obstruction may not present until later in childhood or adulthood.
"Annular" is the adjective for "annulus" (a little ring).
Last Editorial Review: 6/9/2016