ARRS -- Patients with possible appendicitis are typically evaluated using a standard-dose contrast enhanced CT, but a low-dose unenhanced CT that delivers approximately 50% less radiation is just as effective, according to a study performed at the Seoul National University College of Medicine in Seoul, Korea. The standard-dose enhanced CT scan delivers approximately 8.0 mSv of radiation; the low-dose unenhanced CT scan delivers approximately 4.2 mSv of radiation.