Gerotas

Gerotas, in medical anatomy, typically refers to Gerota's fascia, the renal fascia. This dense connective tissue layer envelopes the kidney and the ipsilateral adrenal gland within the retroperitoneum and forms an important anatomic boundary for the perirenal space. The fascia is arranged as anterior and posterior leaves that attach to surrounding structures and fuse laterally, creating a complete sheath around the kidney and adrenal gland. The space inside is known as the perirenal space or Gerota's pouch.

Within Gerota's fascia, the perirenal space contains the kidney, adrenal gland, and perirenal fat, while surrounding compartments such as the posterior and anterior pararenal spaces lie outside the fascia. The fascia thus acts as a partial barrier that can influence the spread of infection, bleeding, or tumor from the kidney or adrenal region.

Clinically, Gerota's fascia is relevant in imaging and diagnosis. CT or MRI assessments of retroperitoneal disease use the fascia as a landmark to determine extent and containment of pathology such as abscesses, hematomas, or neoplasms. Variations in the continuity or thickness of the fascia can affect how disease processes are contained or propagated within the retroperitoneum.

The term is named after the Austrian surgeon Adolph von Gerota, who described the structure in the late 19th to early 20th century. In addition to the fascia, the enclosed space is sometimes referred to as Gerota's pouch, and the broader anatomy is described in terms of renal or perirenal fascia.