is it because of longer duration of ct pet bone scan?
Hi Rohan. This table is meant to help you remember conceptually varios modalities by using the Green-Yellow-Red analogy. There are a few exceptions to this concept - and you have pointed one out here. Yes Barium enema has a higher exposure than Bone scan / CT Head - but protecting a patient in Ba enema by using a lead shield is easier. A CT tube rotates all around the patients body so its very difficult to shield. Also CT is more commonly done now - even in children and hence CT beaing the Red zone is more apt.
thank u sir got it