Capsular Branches of Renal Artery (Right)

Origin

There are three sets of capsular arteries: superior, middle, and inferior (Boijsen, 1959). For the most part, capsular arteries typically arise from the renal artery before dividing into anterior and posterior divisions. However, they may arise from other neighboring arteries such as the abdominal aorta, inferior suprarenal artery, or gonadal artery. Additionally, there may be multiple arteries from multiple sources.

Course

Since the capsular artery is an extrarenal artery, it does not penetrate the parenchyma of the kidney via the hilar aspect. Instead, it passes around the external surface of the kidney before penetrating the renal capsule.

Branches

The capsular branches give rise to several arteries, including:

- branches to the perirenal fat;

- perforating branches that penetrate the renal capsule and anastomose with branches of interlobular arteries;

- anastomotic branches between superior, middle, and inferior renal capsular arteries that provide an arterial arcade along the lateral margin of the kidney.

All of these arterial branches are freely interconnected with each other (Meyers et al., 1967).

Supplied Structures

The capsular branches supply the perirenal fat capsule and provides a source of collateral circulation with the arterial supply of the renal parenchyma primarily served by the intrarenal arterial system.

List of Clinical Correlates

- The capsular artery complex can serve as an important source of collateral circulation in an ischemic kidney (Meyers et al., 1967).

References

Boijsen, E. (1959) 'Angiographic studies of the anatomy of single and multiple renal arteries', Acta Radiol Suppl, 183, pp. 1-135.

Meyers, M. A., Friedenberg, R. M., King, M. C. and Meng, C.-H. (1967) 'The Significance of the Renal Capsular Arteries', The British Journal of Radiology, 40(480), pp. 949-956.