We developed new software that enables three-dimensional (3D) images of the ureter and urethra to be automatically processed from the video image of a conventional endoscope. The entire image of the ureter or urethra is displayed opened in a picture like a 3D map. The locations of lesions and the 3D structure of the prostatic urethra are depicted using this method, which enables quantitative evaluation of lesions and the obstructive potential of the prostatic urethra. Application of the technology in the urinary tract is discussed.