Renal collar which surrounds the aoa has its two limbs split by:
Renal collar The main renal vein divides and sends one limb anterior and another limb posterior to aoa to reach the IVCQ. Formed on the left side and represent persistence of the embryonic state.
Left renal vein
Left renal aery
Isthmus of horseshoe kidney
All of the above
Aerial disorders