Apparently the growth of CT scans has significantly increased the level of radiation the average patient receives in
a year. How do we know? “…preliminary results of a report of the medical subgroup of the National Council on Radiation Protection and Measurement (NCRP)” say so. Apparently, the decision as to whether or not a patient gets a CT (or just plain radiograph) isn’t necessarily standardized. Neither is the level (even ballpark level) of dosage a patient gets from operator to operator…
The size of the increase in the collective annual dose was a surprise to many who attended the conference. The increase stems from the growth in the number of scans being done, and from larger doses delivered by new kinds of scans. CT scans deliver the largest portion of the annual collective dose, 440,000 person-Sv, with chest and abdominal and pelvic scans delivering the largest shares, 17 percent and 58 percent, respectively, of that number. Nuclear medicine procedures account for 220,000 person-Sv of the collective dose, with cardiac studies accounting for more than 85 percent of that total.
Between 1993 and 2006, the number of CT scans grew by more than 10 percent a year, to 62 million scans annually. Multislice CT scanners deliver higher doses of radiation than single-slice scanners, though it’s hard to estimate the doses that patients receive because different machines in the hands of different practitioners deliver doses that vary by as much as a factor of 10.
Holy crap! Can anyone think of another aspect of medicine so poorly controlled? (Wait times don’t count)
In this Medgadgeteer’s experience in the ortho world, the number of scans given to a patient was directly proportional to the perceived likelihood that they might sue the doctor. There’s a decent chance you might lose a suit if Junior’s knee doesn’t recover just right and you failed to order that extra, unnecessary CT. After all, maybe it could have told you something the 3 x-rays and the MRI didn’t. They’re far less likely to come after you for overexposing Junior to radiation.
Also, notably lacking from the article on DOTmed is any indication of where we’re crossing a threshold into potential harm.
Maybe the moral of the story is to use MRI and ultrasound whenever possible.