Horizontal part of duodenum

Pars horizontalis duodeni

  • Latin synonym: Pars inferior duodeni; Pars transversa duodeni
  • Synonym: Inferior part of duodenum; Transverse part of duodenum; Third part of duodenum
  • Related terms: Inferior part; Horizontal part (D3); Inferior part; Horizontal part; Transverse part; Duodenum: Inferior part; Horizontal part; Transverse part; Duodenum (Inferior part; Horizontal part; Transverse part); Duodenum - Inferior part; Horizontal part (D3)

Definition

The horizontal part (D3) of duodenum (pars horizontalis; third or preaortic or transverse portion) is from 5 to 7.5 cm. long.

It begins at the right side of the upper border of the fourth lumbar vertebra and passes from right to left, with a slight inclination upward, in front of the great vessels and crura of the diaphragm, and ends in the ascending portion in front of the abdominal aorta.

It is crossed by the superior mesenteric vessels and the mesentery. Its front surface is covered by peritoneum, except near the middle line, where it is crossed by the superior mesenteric vessels. Its posterior surface is uncovered by peritoneum, except toward its left extremity, where the posterior layer of the mesentery may sometimes be found covering it to a variable extent. This surface rests upon the right crus of the diaphragm, the inferior vena cava, and the aorta. The upper surface is in relation with the head of the pancreas.

This definition incorporates text from a public domain edition of Gray's Anatomy (20th U.S. edition of Gray's Anatomy of the Human Body, published in 1918 – from http://www.bartleby.com/107/).

Comparative anatomy in animals

Translations

Translations