(1) Adrenal gland, (2) Left kidney, (3) Abdominal aorta (4) Inferior phrenic arteries, (5) Superior suprarenal arteries, (6) Middle suprarenal arteries, (7) Inferior suprarenal arteries, (8) Aberrant accessory renal artery, (9) Renal arteries, (10) Testicular arteries
The paired adrenals are located superior to the superior poles of the kidneys, separated only by a thin layer of fatty tissue. Since they are flattened along the posteroanterior axis, they have clearly distinct anterior and posterior aspects. The left adrenal resembles a crescent, while the right gland is mitral shaped. The anterior aspect of the left adrenal is completely covered with peritoneum, while the latter covers only the inferior aspect of the right adrenal. The posterior aspect of both adrenals abuts the lumbar aspect of the diaphragm.
The topography of the right adrenal relates to the liver and inferior vena cava, while the left adrenal reaches the spleen and is separated from the posterior gastric wall by the lesser peritoneal sac. Both adrenals are located at about the level of the 11th/12th thoracic vertebra and enclosed by a vascularized capsule of connective tissue made up of collagen fibers and smooth muscle cells. Adult adrenal glands weigh about five to seven grams.
Blood supply
1. Arteries
Inferior phrenic artery → Superior suprarenal artery
Aorta → Medial suprarenal artery
Renal artery → Inferior suprarenal artery
There are numerous variants!
2. Veins
In each adrenal the venous blood is collected in the central vein which exits the gland through the suprarenal hilum and becomes the left (or right) suprarenal vein.
Right suprarenal vein → Inferior vena cava
Left suprarenal vein → Renal vein
3. Lymphatics
The lymphatics exiting the adrenals primarily parallel the arteries. The primary lymph nodes of the adrenals are the para-aortic and lumbar lymph nodes. Some lymphatics traverse the diaphragm and drain into the posterior mediastinal lymph nodes.