During cystoscopy, a thin instrument with a camera is gently passed through the urethra and into the bladder, allowing your urologist to directly examine the bladder lining. Sterile fluid may be used to expand the bladder slightly so the walls can be seen more clearly. If an unusual, inflamed, or suspicious area is identified, a small sample of tissue can be removed through the scope. This sample is sent to a laboratory for examination under a microscope. The biopsy can help diagnose bladder cancer, inflammation, or other abnormalities and can provide important information for determining whether additional testing or treatment is needed.