Expansion
Renal capsule, perirenal fat, renal (Gerota's) fascia, pararenal fat
Expansion
From the kidney outwards:
- Renal capsule - a tough fibrous coat adherent to the surface
- Perirenal (perinephric) fat - surrounds the kidney and adrenal
- Renal fascia (Gerota’s fascia) - encloses the kidney, adrenal and perirenal fat
- Pararenal fat - outside Gerota’s fascia, mainly posterolateral
Gerota’s fascia is open inferiorly, which allows a perinephric collection or blood to track down towards the pelvis, and explains why a perinephric abscess can point in the loin or the iliac fossa.
Because the fascia forms a natural envelope containing the kidney, adrenal and their fat, radical nephrectomy removes everything within it en bloc.
The fat also cushions the kidney, which is why rapid weight loss can allow the kidney to descend abnormally (nephroptosis).