What is cystoscopy?
Cystoscopy is an invasive examination of the bladder using a special instrument called a rigid cystoscope. The cystoscope is a thin tube with an optical system mounted on it. The device is inserted through the urethra, the bladder is filled with liquid, and the doctor thoroughly examines the walls of the bladder, the openings of the ureters, and the urethra.
Depending on the pathology detected, cystoscopy can transition from a diagnostic procedure to a therapeutic one. The urologist may remove bladder stones with special forceps, extract polyps, or take tissue biopsies.
It's important not to confuse cystoscopy with fibrocystoscopy, as they are different procedures. You can read about what fibrocystoscopy is here.