Renal angiography or Renal Angioplasty refers to the procedure carried out to detect the blockages in the blood vessels to diagnose renal disease. There is, at times blockage of the arteries in the renal region reducing the blood supply to the kidneys.
There is no difference as far as the procedure is concerned except the location of the deployment of the catheter. The catheter is inserted from the same location in the groin / arm, as the case may be. In this case the catheter is moved to the kidneys region instead of the heart.
During renal Angiography usually only non ionic contrast material is used to prevent any lasting effect on the kidneys.