These structures do not form any part of the genito-urinary apparatus, but it is convenient to describe them in association with the glands by which they are supported.
The suprarenal bodies are two solid viscera resting each upon the upper extremity of the corresponding kidney and the adjoining parts of its inner an anterior surfaces, and bound to it by subperitoneal connective tissue. They li against the diaphragm opposite the eleventh rib, or tenth intercostal space, and are separated from each other by a space of about two inches and a half. The left is usually a little higher than the right owing to the greater elevation of its kidney.
The organ varies widely in dimensions within physiological limits. Its average weight is about a drachm, its height an inch and a quarter, and its greatest breadth at the base an inch and three-quarters.
The right suprarenal body is pyramidal in form with the apex directed upward and somewhat inwards. Its anterior surface is related above to a special impression upon the under and back part of the right lobe of the liver, between the layer of the coronary ligament; internally to the inferior vena cava which slightly: overlaps it (Rolleston); and below is covered with peritoneum continuous with that of the kidney, except at its internal inferior angle where it is crossed by the hepatic flexure of the duodenum. It is rather firmly adherent to the liver, and the vessels of the two organs anastomose with each other at this point.
The left suprarenal body is a little larger than its fellow, somewhat crescentic in shape, and encroaches less upon the summit of the kidney than the right, an: more upon the inner border, reaching even to the hilum. Its anterior surface is covered above by the peritoneum of the lesser sac, which separates it from the stomach; and below, near its internal inferior angle, it is crossed by the upper' border of the pancreas and the splenic artery. Externally it is in contact with the upper extremity of the spleen, which passes a little behind it, and its inner border is separated from the aorta by the fibers of the diaphragm.
Accessory suprarenal bodies are often present in the connective tissue around the principal organ.
On section the organ is found to be covered by a thin fibrous capsule which sends trabecular processes between the cellular elements of its proper substance. The parenchyma consists of a peripheral portion, or cortex, of yellowish color, except in its deepest layer which is darkly pigmented, and a central portion or medulla, soft and greyish, and tending to break down under decomposition in such a manner as to give the appearance of an irregular cavity (whence the name suprarenal ' capsule
Vessels and nerves
It is richly supplied both with vessels and nerves. Its arteries are derived from three sources - the aorta, the phrenic, and the renal - and pierce the organ in various places. The veins terminate on the right side in the vena cava, and sometimes by means of small branches in the phrenic and renal trunks; on the left, in the left renal vein. The lymphatics pass to the renal glands, which, like the suprarenal bodies, themselves contain a good deal of pigment. The nerves come from the solar plexus, and include filaments from the sympathetic, the splanchnic, and according to some authors from the phrenic and vagus also. It is disproportionately large in early fetal life, and has nearly reached its full growth at the time of birth.