Peritoneum and Retroperitoneum

1. Kidneys, ureters

2. Uterus, fallopian tubes, prostate

3. Pancreas

4. Aorta, IVC

5. Esophagus (thoracic), duodenum (Second, third, and fourth)

6. Ascending and descending colon, rectum (middle one-third)

7. Adrenal glands

List of intraperitoneal organs

1. Liver, spleen

2. Stomach, duodenum (first part)

3. Jejunum, ileum

4. Cecum, appendix

5. Transverse and sigmoid colon, rectum (upper one-third)

6. Ovaries

Urinary bladder, lower one-third rectum, and distal ureters are infra/subperitoneal in nature.

Peritoneal cavity spaces

Small bowel mesentery is a specialized peritoneal fold extending from the second lumbar vertebra to the right iliac fossa containing blood vessels, nerves, lymph nodes, and fat. It connects jejunum and ileum to posterior abdominal wall and is difficult to appreciate if ascites is not present (Table 12.1).

Omentum: Specialized peritoneal folds.

Lesser omentum: Connects the lesser curvature of the stomach and proximal duodenum with the liver.

Table 12.1 Illustrating various peritoneal cavity spaces

Subphrenic space	Bilateral, inferior to diaphragm
Subhepatic space	Inferior to liver; anterior and posterior Posterior subhepatic space is called Morrison’s space
Lesser sac (Omental bursa)	Between stomach and pancreas
Paracolic gutters	Bilateral; along ascending and descending colon. Right paracolic gutter is larger than left, communicates freely with the right subphrenic space Phrenicocolic ligament partially limits the connection between left paracolic gutter and left subphrenic space
Pelvic	Females—b/w uterus and rectum; also known as rectouterine pouch or POD (Pouch of Douglas) Males—recto vesical pouch; b/w rectum and urinary bladder
Anterior cul-de-sac	Urinary bladder and uterus