Inferior adrenal artery

Perforating arteries, an important collateral pathway to the kidney, arise from the intraparenchymal branches of the renal artery and exit from the kidney to anastomose with various retroperitoneal arteries [18]. In addition to the main renal artery and perforating arteries, the superior, middle, and inferior capsular arteries should be considered as well. The superior capsular artery may arise from the inferior adrenal artery, main renal artery, or aorta. The middle capsular artery, which may consist of one or more branches, arises from the main renal artery. The inferior capsular artery may originate from the gonadal artery, an accessory or aberrant lower pole, or even the main renal artery. These vessels form a rich capsular network that anastomoses freely with perforating arteries and other retroperitoneal (especially lumbar) arteries and also with internal iliac, intercostal, and mesenteric arteries [18]. 

Anatomical Considerations The adrenal gland is supplied by three groups of arteries the superior, middle, and inferior adrenals arise from the inferior phrenic, aorta, and renal arteries, respectively. Infrequently, they originate elsewhere. The number of vessels in each group is quite variable. 

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