Nsclc st4. diagnostic ct scans used iodine contrast but due to allergy, post treatment ct scans used barium. how accurate/comparable are the scans?

CT.: Iodine contrast highlights the vessels on ct (arteries/veins) so it is easier to detect lymph nodes or other tumors. Barium highlights the stomach, small and large intestine. This allows easier detection of abdominal tumors. A ct without contrast is difficult to interpret. Could consider MRI with gadolinium contrast (different than iodine) if need be. Best discussed with your oncologist.

Not at all: Barium is an oral agent, and cannot be given intravenously. If you are allergic to iodine, you should be treated with a steroid prep prior to administration of iodine contrast.