Cystoscopy is endoscopy of the urinary bladder via the urethra. It is carried out with a cystoscope.

The urethra is the tube that carries urine from the bladder to the outside of the body. The cystoscope has lenses like a telescope or microscope. These lenses let the physician focus on the inner surfaces of the urinary tract. Some cystoscopes use optical fibres (flexible glass fibres) that carry an image from the tip of the instrument to a viewing piece at the other end. Cystoscopes range from pediatric to adult and from the thickness of a pencil up to approximately 9 mm and have a light at the tip. Many cystoscopes have extra tubes to guide other instruments for surgical procedures to treat urinary problems.

There are two main types of cystoscopy—flexible and rigid—differing in the flexibility of the cystoscope. Flexible cystoscopy is carried out with local anaesthesia on both sexes. Typically, a topical anesthetic, most often xylocaine gel (common brand names are Anestacon and Instillagel) is employed. The medication is instilled into the urethra via the urinary meatus five to ten minutes prior to the beginning of the procedure. Rigid cystoscopy can be performed under the same conditions, but is generally carried out under general anesthesia, particularly in male subjects, due to the pain caused by the probe. The sizes of the sheath of the rigid cystoscope are 17 French gauge (5.7 mm diameter), 19 Fr gauge (6.3 mm diameter), and 22 Fr gauge (7.3 mm diameter).

Cystoscopy may be recommended for any of the following conditions:

If a patient has a stone lodged higher in the urinary tract, the physician may use a much finer calibre scope called a ureteroscope through the bladder and up into the ureter. (The ureter is the tube that carries urine from the kidney to the bladder.) The physician can then see the stone and remove it with a small basket at the end of a wire that is inserted through an extra tube in the ureteroscope. For larger stones, the physician may also use the extra tube in the ureteroscope to extend a flexible fiber that carries a laser beam to break the stone into smaller pieces that can then pass out of the body in the urine.^{[citation needed]}

Physicians may have special instructions, but in most cases, patients are able to eat normally and return to normal activities after the test. Patients are sometimes asked to give a urine sample before the test to check for infection. These patients should ensure that they do not urinate for a sufficient period of time, such that they are able to urinate prior to this part of the test.

Patients will have to remove their clothing covering the lower part of the body, although some physicians may prefer if the patient wears a hospital gown for the examination and covers the lower part of the body with a sterile drape. In most cases, patients lie on their backs with their knees slightly parted. Occasionally, a patient may also need to have his or her knees raised. This is particularly true when undergoing a Rigid Cystoscopy examination. For flexible cystoscopy procedures the patient is almost always alert and a local anesthetic is applied to reduce discomfort. In cases requiring a rigid cystoscopy it is not unusual for the patient to be given a general anesthetic, as these can be more uncomfortable, particularly for men. A physician, nurse, or technician will clean the area around the urethral opening and apply a local anesthetic. The local anesthetic is applied direct from a tube or needleless syringe into the urinary tract. Often, skin preparation is performed with chlorhexidine.

Patients receiving a ureteroscopy may receive a spinal or general anaesthetic.