Endoscopy of the urinary bladder via the urethra is called cystoscopy. Diagnostic cystoscopy is usually carried out with local anaesthesia. General anaesthesia is sometimes used for operative cystoscopic procedures.

When a patient has a urinary problem, the doctor may use a cystoscope to see the inside of the bladder and urethra.

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 doctor 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. The cystoscope is as thick as a pencil and has 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 using local anaesthesia on both sexes. Typically, lidocaine gel (such as the brand name Instillagel) is used as an anaesthetic, instilled in the urethra. Rigid cystoscopy can be performed under the same conditions, but is generally carried out under general anaesthesia, particularly in male subjects, due to the pain caused by the probe.

From http://en.wikipedia.org/wiki/Cystoscopy