Which characteristic is NOT improved by compression in mammographic imaging?

The characteristic that is not improved by compression in mammographic imaging is spatial resolution. Compression during mammography serves several key purposes: it reduces patient motion, minimizes the effects of scattered radiation, and helps to alleviate geometric blurring. By compressing the breast tissue, the overall thickness is reduced, which helps to achieve better imaging quality by increasing contact and uniformity.

However, spatial resolution refers to the ability to distinguish between small structures within the imaged tissues. While compression can help improve the clarity of certain aspects of the image due to reduction in motion and scatter, it does not inherently improve spatial resolution. Spatial resolution is primarily influenced by the imaging system's characteristics, such as the film or digital detector’s capabilities and the focal spot size of the x-ray beam. Therefore, while compression has many benefits in terms of image quality, it does not enhance the fundamental limits of spatial resolution determined by the system itself.