The left fallopian tube (T) is being elevated by the probe. The blood supply to the left tube and ovary (BS) is seen, while the left ureter (U) is seen beneath the transparent peritoneum. A yellowish plaque of endometriosis (arrow) is seen directly over the ureter. Surgeons would be hesitant to treat such a lesion with laser vaporization or electrocoagulation because damage to the underlying ureter might result. Excision of endometriosis can treat any manifestation of the disease anywhere in the pelvis and is ideal for such a lesion.