A radiographic reference marker which facilitates the accurate calculation of the degree of magnification or minification or minimization of radiographic images includes a reusable portion and a disposable portion. The reusable portion includes a radiopaque sphere of outside diameter d1, and a radiolucent plastic housing capable of frictionally but removably engaging the sphere and including a plate attaching face and a housing attaching face. The plate attaching face includes in a center portion thereof an aperture of a diameter capable of allowing passage therethrough of the sphere, and the housing attaching face includes a first portion of a means for removably attaching the reusable portion to the disposable portion. The reusable portion also includes an attenuating plate having a first surface and a second surface, a thickness sufficient to attenuate radiation, and a component for removably attaching the second surface of the attenuating plate to the plate attaching face of the plastic housing. The disposable portion includes a mounting substrate having a substrate attaching face and a mounting face, and the substrate attaching face includes a second portion of the component for removably attaching the reusable portion to the disposable portion. The mounting face also includes a component for removably attaching the mounting substrate to a subject.
展开▼