Bifurcation level of the aorta: landmark for pelvic irradiation.

The position of the aortic bifurcation in women in relation to the lumbar vertebral bodies was determined in 100 pelvic arteriograms to provide some help in teleradiation therapy planning for pelvic malignancies. It was found that in order to cover the area of the aortic bifurcation, the radiation field should extend to the top of the body of the fourth lumbar vertebra.