Cutting for stone. A cutting operating for the removal of a calculus.

Lithotomy from Greek for "lithos" (stone) and "thomos" (cut), is a surgical method for removal of calculi, stones formed inside certain hollow organs, such as the bladder and kidneys (urinary calculus) and gallbladder (gallstones), that cannot exit naturally through the urethra, ureter or biliary duct. The procedure, which is usually done by means of a surgical incision (therefore invasive), differs from lithotripsy, whereas the stones are crushed either by a minimally invasive probe inserted through the exit canal, or by ultrasound waves (extracorporeal lithotripsy), which is a non-invasive procedure.