Roentgen stereophotogrammetry for evaluation of liver volume and shape.

Model experiments and tests on 2 patients were performed to probe the feasibility of roentgen stereophotogrammetry for evaluating variations in shape and volume of the liver. The surface of the object was marked with indicators, and the three-dimensional marker coordinates were determined. The model experiments demonstrate a good correlation between true volume and the volumes defined by the indicators, and also demonstrate the possibility of localizing an expansivity. The variability of the volume of a polyhedron defined by 15 liver indicators with stage of breathing is discussed.