How images are obtained  


The resulting 2 dimensional x-ray image is a summation of all of the structures through which the x-ray beam passed; structures are superimposed on the film.

Films are viewed as though you were looking at the patient from the front. The patient's right side is displayed on the left of the image, and the left side on the right.

The more that the x-ray beam is attenuated by the tissues it passes through, the lighter the structures appear on the x-ray image. Most structures appear as varying shades of gray. Tissues which attenuate more of the x-rays appear whiter on the image, while tissues which attenuate less of the x-rays appear blacker on the image.