Prostate after laser surgery. Image 10 of 10. Endoscope image of the urethra after greenlight HPS laser surgery to treat benign prostatic hyperplasia (BPH), a non-cancerous enlargement of the prostate gland. The prostate sits underneath the bladder, surrounding the urethra, the tube that carries urine from the bladder out of the body. BPH had caused narrowing of the urethra and difficulty passing urine. The laser vaporised prostate cells from within the urethra, therefore widening it. This is minimally invasive surgery and requires minimal aftercare. It does not cause bleeding as the heat from the laser cauterises any blood vessels hit. For a sequence of images showing laser surgery of this prostate see M865/317-M865/325.