Arterial arcades

Arterial arcades
Loop of small intestine showing distribution of intestinal arteries
Dorlands /Elsevier	a_56/12149518
Anatomical terminology []

The arterial arcades (intermesenteric arterial anastomoses or Riolan arcades) are loops of arteries around the jejunum and ileum.

Nearest the duodenum the mesenteric loops are primary, the vasa recta are long and regular in distribution, and the translucent spaces (lunettes) are extensive.

Toward the ileocolic junction, secondary and tertiary loops are observed, the vessels are smaller and become obscured by numerous fat-tabs.

The diagrams below show the arrangement and variations of the loops of the mesenteric vessels for various segments of the small intestine of average length:

Arterial arcades

Arterial arcades

Loop of small intestine showing distribution of intestinal arteries

Loop of small intestine showing distribution of intestinal arteries

Loop of small intestine showing distribution of intestinal arteries

Loop of small intestine showing distribution of intestinal arteries

Loop of small intestine showing distribution of intestinal arteries

Loop of small intestine showing distribution of intestinal arteries

This article incorporates text in the public domain from the 20th edition of Gray's Anatomy (1918)