Left colic artery

Branch

First branch of the IMA, passing retroperitoneally to the left across the psoas, left ureter and gonadal vessels before dividing into an ascending branch (to the splenic flexure, meeting the middle colic) and a descending branch to the descending colon.

Traced from the start

  1. Abdominal aorta
  2. Inferior mesenteric artery
  3. Left colic artery

Detail

Supplies
Distal third of transverse colon, splenic flexure, descending colon
Anastomosis
Ascending branch ↔ left branch of middle colic at Griffiths' point
Course
Retroperitoneal, in front of the left ureter and gonadal vessels

When it goes wrong

Ascending branch fails to meet the middle colic — marginal artery deficient or absent at the flexure in up to ~18%

Splenic flexure becomes an end-territory: ischaemic colitis after hypotension, AAA repair or IMA ligation

Left ureter crossed by the artery and its mesocolon

Ureteric injury during left colectomy or sigmoid mobilisation unless the ureter is identified first

Practise this structure

1 question in the bank tagged Hindgut.