Retroperitonium

Retroperitoneum is an anatomical space in the abdominal cavity behind the peritoneum. It is located between the posterior parietal peritoneum and the posterior abdominal wall. The retroperitoneum contains several important structures, including the kidneys, adrenal glands, pancreas, duodenum, ascending and descending colon, and major blood vessels such as the aorta and inferior vena cava.

Anatomy

The retroperitoneum is divided into three spaces: the anterior pararenal space, the perirenal space, and the posterior pararenal space. Each of these spaces contains different organs and structures.

Anterior Pararenal Space

The anterior pararenal space contains the pancreas, ascending and descending colon, and the second to fourth parts of the duodenum.

Perirenal Space

The perirenal space contains the kidneys, adrenal glands, and perirenal fat.

Posterior Pararenal Space

The posterior pararenal space is a fat-filled space that does not contain any major organs.

Clinical Significance

The retroperitoneum is clinically significant because it is a potential space for disease processes such as infection, hemorrhage, and malignancy. Retroperitoneal fibrosis, a rare disease characterized by the presence of inflammatory and fibrous tissue in the retroperitoneum, can lead to the entrapment and compression of retroperitoneal structures, particularly the ureters, causing hydronephrosis and renal failure.

Imaging

Imaging of the retroperitoneum is typically performed with computed tomography (CT) or magnetic resonance imaging (MRI). These imaging modalities can provide detailed information about the anatomy of the retroperitoneum and can help in the diagnosis of retroperitoneal diseases.

The retroperitoneum (red) and its surrounding structures.

See Also

• Peritoneum
• Kidneys
• Adrenal glands
• Pancreas
• Duodenum
• Ascending colon
• Descending colon
• Aorta
• Inferior vena cava