1. A method for generating a planar medical image of a portion of the human anatomy, comprising the steps of: providing a computer having a 3-D stored image of said portion of the human anatomy; creating a first image slice of the 3-D stored image at a first image orientation and depth and defining a first point in the first slice; creating a second image slice of the 3-D stored image at a second image orientation and depth and defining a second point in the second slice; creating a third image slice of the 3-D stored image at a third image orientation and depth and defining a third point in the third slice; calculating a plane in the 3-D stored image described by the three points; and creating a fourth image slice of said 3-D stored image as said planar medical image from said calculated plane.