Quantitative estimates of the benefits are not cited alongside any quantitative estimates of risk of radiation-based imaging procedures. This alone—expression of benefit in purely qualitative terms versus expression of risk in quantitative, and therefore seemingly more certain terms—may well contribute to a skewered sense of the relative benefits and risks of diagnostic imaging among health-care providers as well as patients. The current paper, therefore, quantitatively compares the benefits of diagnostic imaging in several cases, based on actual mortality or morbidity data if ionizing radiation were not employed, with the linear no-threshold (LNT) model-derived (i.e., theoretical) estimates of radiogenic cancer mortality. The case studies presented provide at least approximate estimates of medical benefit and illustrate the very large benefit-to-risk ratios typical of diagnostic imaging studies.