Large Intestine

Question 1

Extent of the large intestine

Answer 1

Ileocecal junction to anus

Question 2

Length of large intestine

Answer 2

1.5m

Question 3

Divisions of large intestine

Answer 3

Cecum
Ascending colon
Right colic flexure
Transverse colon
Left colic flexure
Descending colon
Sigmoid colon
Rectum
Anal canal

Question 4

What are the features of the large intestine?

Answer 4

Teniae coli
Appendices epiploicae
Sacculations

Question 5

Lymph nodes of the large intestine

Answer 5

Epicolic lymph nodes: Lying on the wall of the gut
Paracolic nodes: On the medial side of the ascending and descending colon and near the mesocolic border of the transverse and sigmoid colon
Intermediate nodes: On the main branches of the vessels
Terminal nodes: On the superior and inferior mesenteric vessels

Question 6

Which lymph nodes should be removed in case of carcinoma of the large intestine?

Answer 6

The related paracolic and intermediate lymph nodes have to be removed
Their removal is possible only after the ligature of the main branch of the superior or inferior mesenteric artery along which these lymph nodes lie
For this, a larger segment of the bowel than is actually required by the extent of the disease needs to be removed in order to avoid gangrene

Question 7

How can the large intestine be viewed?

Answer 7

Colonoscopy

Question 8

What is a diverticulum?

Answer 8

A diverticulum is a small evagination of the mucous membrane of the colon at the entry point of the arteries
Its inflammation is called diverticulitis

Question 9

What are the features of the cecum?

Answer 9

A large sac forming the commencement of the large intestine

Question 10

Location of the cecum?

Answer 10

Right iliac fossa above the lateral helf of inguinal ligament

Question 11

Connections of the cecum

Answer 11

Communicates superiorly with ascending colon, medially at the level of caecocolic junction with ileum, and posteromedially with the appendix

Question 12

Dimensions of the cecum

Answer 12

It is 6 cm long and 7.5 cm broad

Question 13

Anterior relations of the cecum

Not necessary for exam

Answer 13

Coils of intestine and anterior abdominal wall

Question 14

Posterior relations of the cecum

Not necessary for exam

Answer 14

Muscles: Right psoas and iliacus
Nerves: Genitofemoral, femoral and lateral cutaneous nerve of thigh (all of the right side)
Vessels: Testicular or ovarian
Appendix in the retrocaecal recess

Question 15

Describe the blood supply of the cecum

Answer 15

The arterial supply of the caecum is derived from the caecal branches of the ileocolic artery
The veins drain into the superior mesenteric vein

Question 16

Nerve supply of the cecum

Answer 16

The nerve supply is same as that of the midgut (T11 to L1; parasympathetic,vagus)