Digital Twin technology, or the application of predictive analytics to fields as diverse as manufacturing and space science, is now being considered in the context of healthcare. The attraction is obvious: if one can develop a computer model of a patient, perhaps one can test treatments on the model before applying them to the individual. Rather than using a patient as a beta test for a clinical approach, potential complications can be identified before they can become life threatening. Treatments could be optimized, then applied. At least, that is the hope.