Peritoneal Cavity Spaces
Peritoneal cavity spaces are compartments within the peritoneum that facilitate organ movement and fluid distribution.
The peritoneal cavity is a potential space between the parietal and visceral layers of the peritoneum. Although this cavity normally contains only a small amount of lubricating serous fluid, it is subdivided into anatomical compartments and spaces by reflections of the peritoneum. These subdivisions are crucial for the movement of peritoneal fluid, the spread of infections, abscesses, blood, or tumors, and for surgical access and imaging interpretation. Understanding the peritoneal cavity spaces is essential for clinicians dealing with abdominal trauma, disease localization, and operative procedures.
Overview of the Peritoneal Cavity
The peritoneal cavity is completely enclosed in males but communicates with the exterior in females via the uterine tubes, uterus, and vagina. It is divided into the greater sac and the lesser sac (omental bursa), with several dependent spaces or recesses formed by folds of peritoneum.
- Greater sac: The main compartment of the peritoneal cavity, extending from the diaphragm to the pelvic cavity
- Lesser sac (omental bursa): A smaller compartment behind the stomach and lesser omentum
- Epiploic (omental) foramen: Connects the greater and lesser sacs
Major Peritoneal Spaces and Compartments
1. Supracolic and Infracolic Compartments
The greater sac is divided by the transverse colon and its mesocolon into two main compartments:
- Supracolic compartment: Located above the transverse colon; contains the liver, stomach, and spleen
- Infracolic compartment: Located below the transverse colon; contains the small intestine and ascending/descending colon
2. Right and Left Infracolic Spaces
These are subdivisions of the infracolic compartment formed by the attachment of the mesentery of the small intestine:
- Right infracolic space: Between the mesentery and ascending colon
- Left infracolic space: Between the mesentery and descending colon
3. Paracolic Gutters
Paracolic gutters are longitudinal peritoneal recesses that lie lateral to the ascending and descending colon. They allow for the movement of peritoneal fluid and potentially infectious materials.
Paracolic Gutter | Location | Clinical Note |
---|---|---|
Right paracolic gutter | Lateral to ascending colon | Communicates freely with hepatorenal recess and pelvis |
Left paracolic gutter | Lateral to descending colon | Less deep; limited superiorly by phrenicocolic ligament |
Lesser Sac (Omental Bursa)
The lesser sac lies posterior to the stomach and lesser omentum and allows for free movement of the stomach during digestion.
Boundaries of the Lesser Sac
- Anterior: Stomach, lesser omentum
- Posterior: Pancreas, left kidney, adrenal gland
- Superior: Caudate lobe of liver
- Inferior: Greater omentum
- Left: Spleen and gastrosplenic ligament
- Right: Epiploic foramen (connects to greater sac)
It is the site of posterior gastric ulcer perforations and pancreatic fluid collections.
Pelvic Peritoneal Spaces
In the pelvis, peritoneal reflections between organs create recesses that vary between sexes and are clinically important for fluid accumulation.
In Males
- Rectovesical pouch: Between rectum and bladder; the most dependent part of the peritoneal cavity in males
In Females
- Vesicouterine pouch: Between bladder and uterus
- Rectouterine pouch (Pouch of Douglas): Between uterus and rectum; the most dependent part of the peritoneal cavity in females
Hepatorenal Recess (Morison’s Pouch)
This is a deep recess located between the right lobe of the liver and the right kidney. It is the most dependent space in the supine position and a common site of fluid accumulation from:
- Ascites
- Hemoperitoneum (trauma)
- Infection (e.g., perforated ulcer, appendicitis)
Boundaries
Clinical Importance of Peritoneal Spaces
Ascites
- Excess peritoneal fluid often accumulates in dependent spaces such as pelvis and hepatorenal recess
- Common in cirrhosis, malignancy, and heart failure
Peritonitis and Fluid Spread
- Infection or inflammation can spread via gravity and fluid movement through peritoneal spaces
- Right paracolic gutter may transmit infection from pelvis to subphrenic space
Abscess Formation
- Localized abscesses may form in:
- Subphrenic spaces
- Pelvic pouches
- Lesser sac (e.g., post-pancreatitis)
Peritoneal Dialysis
- Access to peritoneal cavity spaces, particularly pelvis, is used therapeutically in renal failure
Summary of Key Peritoneal Spaces
Space | Location | Key Notes |
---|---|---|
Supracolic | Above transverse colon | Liver, stomach, spleen |
Infracolic (R & L) | Below transverse colon | Small intestine and colon |
Paracolic gutters | Lateral to ascending/descending colon | Fluid spread pathways |
Lesser sac | Behind stomach | Posterior ulcer and pancreas site |
Hepatorenal recess | Between liver and kidney | Fluid collects here when supine |
Rectouterine pouch | Female pelvis | Lowest point in upright position |
Rectovesical pouch | Male pelvis | Lowest point in males |
Last updated on May 8, 2025