A doctor can diagnose some disorders of the bladder and urethra (for example, bladder tumors Bladder Cancer Most bladder cancers arise from the cells that form the innermost layer of the bladder. These cells, called transitional cells or urothelial cells, allow the bladder to stretch when it is full... read more , stones in the bladder Stones in the Urinary Tract Stones (calculi) are hard masses that form in the urinary tract and may cause pain, bleeding, or an infection or block of the flow of urine. Tiny stones may cause no symptoms, but larger stones... read more 
, benign prostatic enlargement Benign Prostatic Hyperplasia (BPH) Benign prostatic hyperplasia (BPH) is a noncancerous (benign) enlargement of the prostate gland that can make urination difficult. The prostate gland enlarges as men age. Men may have difficulty... read more ) by looking through a flexible viewing tube (cystoscope, a type of endoscope). A cystoscope has a diameter about the size of a pencil, and about 6 to 12 inches (15 to 30 centimeters) of the scope are inserted into the urethra and bladder. Most cystoscopes are fiber-optic and contain a light source and a small camera, which allows the doctor to view the inside of the bladder and urethra. Many cystoscopes also contain tools that allow the doctor to obtain a sample (biopsy) of the bladder lining Bladder biopsy Site-specific biopsies and cell sampling are also used in the evaluation of people with suspected kidney and urinary tract disorders. (See also Overview of the Urinary Tract.) A kidney biopsy... read more .
Cystoscopy can be done while a person is awake and causes only minor discomfort. The doctor usually inserts an anesthetic gel into the urethra before the procedure. Possible complications include minor bleeding and infection.
(See also Evaluation of Kidney and Urinary Tract Disorders Evaluation of Kidney and Urinary Tract Disorders A doctor obtains a medical history by interviewing a person. The interview includes questions about a person's symptoms, past medical history (what disorders the person has had), drugs (prescribed... read more .)
