Peritoneal spaces and reflections that form ligaments,
mesentery and omentum are frequently involved secondary to inflammatory,
infectious,
traumatic and neoplastic diseases.The peritoneal spaces,
reflections and the natural flow of peritoneal fluid determine the route of spread of disease processes.
Hence,
an accurate knowledge of imaging anatomy allows localisation of pathology and help in narrowing the differential diagnoses.
Fig. 2: Schematic representation of peritoneal linings and cavity.
Peritoneal cavity is a potential space between parietal and visceral peritoneum. In men,
the peritoneal cavity is closed,
but in women,
it communicates with the extraperitoneal pelvis exteriorly through the fallopian tubes,
uterus,
and vagina,
providing a potential pathway for pathogens to enter.
Peritoneal ligaments are double layers or folds of peritoneum that support a structure within the peritoneal cavity, omentum and mesentery are specifically named peritoneal ligaments.
Basic Embryologic Characteristics
The primitive gut forms within the abdominal cavity and is suspended by two peritoneal reflections called the primitive mesenteries. The position of gut within the primitive mesentery plane divides it into ventral and dorsal portions. Vascular and lymphatic vessels and nerves that supply the abdominal viscera are enfolded within the plane of primitive mesentery.
Ventral part of ventral mesentery forms the falciform ligament and dorsal part of ventral mesentery forms the lesser omentum.
Ventral part of the dorsal mesentery forms the gastrosplenic ligament and dorsal part forms the splenorenal ligament.
Liver also arises in the ventral mesentery,
whereas the stomach, spleen and pancreatic tail develop in the dorsal mesentery. As liver expands in the 5th and 6th weeks of gestation,
stomach and spleen are pushed to the left,
and pancreatic tail fuses with the retroperitoneum.
Fig. 3: Basic embryology of peritoneum. 1 - falciform ligament. 2- Gastrohepatic ligament. 3- Gastrosplenic ligament. 4- Splenorenal ligament.
References: Minu Mohandas