The left calyx stone is also a kidney stone. The anatomy of the kidney is divided into the calyces, calyces and pelvis. Several renal calyces converge into a renal calyx, and several renal calyces converge into a renal pelvis, which continues into the ureter outside the bladder urethra. The stone then passes through the calyces into the calyces into the renal pelvis, the renal pelvis into the ureter, and into the bladder and out of the body. Stones in the calyces also require treatment, but this is determined by the location of the kidney, the size of the stone, whether it is causing infection, and whether it is combined with fluid in the calyces. Usually stones in the calyces do not have any symptoms, and if they are not combined with fluid in the kidney, they usually do not have symptoms of back pain. It is also difficult to change the size of the calyx stone, but if the stone grows progressively in a short period of time, or if it is accompanied by inflammation of the kidney with hydronephrosis, then active treatment is recommended. Treatment may include extracorporeal shock wave lithotripsy or laser lithotripsy under ureteroscopy.