1. A user interface for the display or editing of a three dimensional image, wherein the user interface is provided on a display and is responsive to user inputs in a medical imaging system, the user interface comprising: a framing tool operable to define a region of interest on the medical image; an image matrix including a plurality of cross-sectional images each corresponding to a cross-section of the medical image at one of a plurality of cut planes within the region of interest; and one or more reference views of the medical image each including a plurality of reference indicia that each corresponds to a location of one of the plurality of cut planes.