An incision into the the renal pelvis and kidney in order to remove stones.
Nephr/o/pyel/o/lith/o/tomy
nephr/o- kidney
pyel/o-renal pelvis
lith/o- stones
-tomy- surgical incision
The correct term is nephrolithotomy, which is a procedure to remove kidney stones. The procedure is normally used when kidney stones are too large to be passed through the body.
Nephrolithotomy is surgical incision of the kidney to remove a stone.