That is the question: contrast CT or non contrast CT? it is very difficult sometimes to answer, but for some facts such as r/o of appy, divericulitis and other pathologies, why do we need Contrast CT? as an emergency physician, it is a matter of 2-4 hours of delayed disposition and increased LOS, more cost, more complications (Allergic reaction , Renal failure,..). I found this article very useful at least for acute appendicits, hope more come from our radiology colleagues