"The values in the table are referenced to the ratios of whole-body cancer doses from "Radiation and Human Health," (Gofman, Sierra Club, 1981) Tables 21 and 22.  Why the table stops at age 55 I don't know, but it certainly suggests that, at age 72, Bev's sensitivity to ionizing is relatively low.
But I guess that, like everything else in treatment decisions, it's a tradeoff of information vs. risk."

<b>Contrast Can Be Dangerous</b>
IF contrast medium is a problem because of allergy or potential kidney problems, surveillance could be done with ultrasound or MRI of abdomen, and Chest X-ray for the lung.  Alternatively, one could do the CT without contrast.

<b>Allergic reaction to intravenous contrast medium</b>
The iodinated dye that is injected into patients can cause anaphylactic shock, if the patient is or has suddenly become allergic to it.  Allergy to seafood [also containing organic iodine compounds] is a warning clue.  It is for this reason that <b>THERE MUST ALWAYS BE A DOCTOR IN ATTENDANCE</b> whenever an injection of contrast material is given.


<b>Kidney risk association with intravenous contrast medium</b>
Neil commented:
"Joan wrote about "contrast scans after nephrectomy". I thought there might be some interest in the following information."

<b>Prevention of Contrast-Induced Kidney Failure</b>
One of the limitations of contrast studies such as cardiac catheterization and CT scanning is decrease in kidney function resulting from exposure to radiographic agents. <b>Most patients do not experience worsening of their kidney function.</b> For those who do, it can be a serious problem. <b>It is frequently possible to identify patients at risk. Those with pre-existing kidney disease, diabetes, dehydration, and prior problems when exposed to x-ray dye are usually at risk for transient decreases in kidney function as are patients on certain types of drugs (eg, ACE inhibitors) and those given large volumes of radiographic contrast. Some patients with moderate to severe kidney disease before exposure to contrast will risk the need for temporary or even permanent dialysis. One of the better deterrents against this problem is adequate hydration with intravenous saline prior to the dye study.</b>  One thing that you can do is drink at least two quarts of clear liquids on the day of the scan. 
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Recent evidence has suggested that the antioxidant, acetylcysteine [n-acetyl cysteine], administered before and after dye exposure significantly reduces the risk. This drug is traditionally used to treat Tylenol overdoses. Tepel and associates (N Engl J Med 2000;343:180) studied 83 patients with modest chronic renal insufficiency (baseline creatinine 2.4 mg/dl) who underwent CT scanning with radiographic contrast. Patients were treated with oral acetylcysteine 600 mg twice daily before and after contrast exposure. Compared to placebo, administration of Acetylcysteine significantly prevented worsening kidney function by 48 hours after contrast administration (2% vs 21% had a creatinine increase of > 0.5mg/dl). Also, patients given the drug actually had a significant decrease in their baseline creatinine at 48 hours.]

Another discussion of the same study can be found at &&url.
This site contains additional information provided to the site by the authors of the referenced study.