A longitudinal plane about 1 cm behind the lateral convex border, between the anterior and posterior arterial divisions
Expansion
The renal artery divides into five segmental arteries, apical, upper, middle, lower and posterior. These are end arteries: there is no collateral circulation between segments, so occluding one produces a wedge-shaped infarct.
The anterior division supplies four segments and the posterior division supplies one. The relatively avascular plane between their territories is Brödel’s line, lying about 1 cm behind the lateral convex border of the kidney.
An incision along this line, as in an anatrophic nephrolithotomy, divides fewer vessels and preserves more parenchyma than a random incision.
The same principle guides percutaneous access for nephrolithotomy: puncture is aimed through a posterior calyx along the axis of the infundibulum, entering through this avascular plane rather than through the vascular renal hilum.