'Hey, you with that green glow in your hair'

C.P. Kaiser, Editor

One thing is for certain about the Radiological Society of North America (RSNA) meeting, which took place this past week in Chicago: There was much discussion about radiation exposure from medical imaging. While no one is turning green, as the Aquabats suggest in the "Radiation Song," there still is a need to be ever vigilant about achieving ALARA.

Researchers have been focusing for years on lowering the dose from CT scans. However, a study presented at the meeting suggests the risk of radiation-induced cancer may be lower than previously thought. The retrospective study is large, but it also looked at Medicare-aged patients. The benefit of an appropriate CT scan for patients 65 years and older generally outweigh the risk of developing cancer in 10 to 20 years. However, the findings also documented an increase in CT scans in the years examined.

The lesson for cardiologists is to be aware that your patients do not live in a medical vacuum. The ionizing radiation imaging studies you order are most likely not the first ionizing radiation studies of your patients' lifetime. We're getting closer to tracking radiation exposure through the EMR, but we're not there yet. It is incumbent to consider prior medical exposure to radiation when ordering tests.

A debate at the meeting centered around the validity of extrapolating data from atomic bomb survivors to pertain to the risks from CT scans. This debate will likely continue until millions of CT-scanned patients are followed for 20 years. The participants, however, seemed to delivere persuasive arguments, as the audience left evenly split between the two sides.

A study from Circulation found that acute MI patients are exposed to a large cumulative dose of radiation during an average four-day inpatient stay. The researchers noted that studies generally track individual dose exposures and they call for tracking radiation exposure during the continuum of care.

On the bright side, researchers in Philadelphia have developed a protocol to lower dose in the cath lab for children undergoing electrophysiology procedures. It's actually a quite simple method that involves using a low-dose fluoro setting and initiating alerts when radiation threshold levels have been reached. This allows the EPs to adjust dose and camera angles in real time to minimize exposure.

In the "Radiation Song," the singer tells us he bought a lead ascot for protection. It reminds me of a recent trip to the dentist with my young boys, both under 10 years. When they needed x-rays, the dentist not only outfitted them with the standard lead chest guard, she also wrapped what amounted to a lead ascot around their necks to protect their thyroid glands.

We've come a long way in our awareness of medical radiation exposure. What protocols do you have for reducing radiation exposure: in the cath lab or the imaging suite? We'd like to know.

Thank you,
C.P. Kaiser
Editor of Cardiovascular Business