If your having it with a dye study, then make sure you have somebody good that can get you on 1 stick with your IV, exspecially if your a hard stick. You dont want to have to be stuck multiple times as that can flair the RSD. Im a hard stick, and unfortantly for me I usally end up with an RSD flair. And because its a CT and not an MRI, it will be shorter, so you should be ok with being comfortable, However ask how long your CT is booked for (because that meens roughly how long the ct or mri will take) and if its going to be long, then make sure to have extra meds on board to keep comfortable. And thats for anybody, exspecially if your having an MRI! Because the least MRIs usally take is 30min.