Images from a cystoscopy. The top two images show the interior of a bladder. The top left image shows the bladder wall, the top right shows the cystoscope passing into the bladder from the urethra. The bottom two images show an inflamed urethra.
Photo credit: Cystoscopy carried out on Michael Reeve (29-year-old male), 25 April, 2005, at the North London Nuffield Hospital