The urinary system is made up of the kidneys, ureter (the narrow, muscular tube that connects your kidney to your bladder), bladder, and urethra (a tube that allows urine to pass through the bladder and out of the body). A ureteroscopy is a procedure that looks into the ureter and kidney. It involves inserting a special telescope, called a ureteroscope, into the urethra and then passing it through to the bladder and then on into the ureter and kidney. The operation is usually performed under a general anesthetic. This means that you are asleep during the procedure. There are risks associated with having a general anesthetic, but they are small. Occasionally a spinal anesthetic is used (where a needle is put in your back to numb you from the waist down) – your anesthetist will discuss the type of anesthetic you need you. You should have received a copy of the leaflet Having an anesthetic. If you have not, please ask your doctor or nurse for a copy. The ureteroscope is about the thickness of a pencil and has a tiny camera on one end, so the doctor can view an image of your urinary system on a screen. It is usually used to treat kidney stones, but it is also used to help make a diagnosis for unexplained bleeding, assessment of some cancers in the ureter or kidney and to check if treatments have worked.