Abstract: New techniques, imaging software, and related imaging systems for visualizing and comparing medical images are disclosed. The apparatus of this invention generally comprises a digital imaging system including a visual display device in combination with software adapted so as to enable two or more digital images to be rapidly alternately superimposed on the same display space and displayed to a viewer (FIG. 7). The digital blink comparator apparatus and methods of this invention may be carried out using or be applied to a wide variety of existing medical imaging interpretation devices including, but not limited to, standard PACS, web-based PACS, cardiac imaging, ophthalmologic imaging, and dental imaging.