CT scans of special concern . . .
A Diagnostics & Imaging Week Staff Report
"Managing in the presence of data is far better and easier than managing in its absence."
That was the keynote, and very basic, statement summarizing the point of a recent meeting in Vienna, Austria, of the International Atomic Energy Agency (IAEA; Vienna).
But for patients, that basic tenant is overlooked or, perhaps more accurately, entirely ignored in radiation technology, according to that organization. And that absence is correctable, with the development of new information technology in healthcare.
The IAEA is proposing the use of a "Smart Card," or equivalent electronic collection system, as part of, or supplement to, an electronic medical record (EMR) that will document the amount of radiation an individual receives over his or her lifetime.
The need for this type of documentation is critical, those at the IAEA say, given the increasing use of ionizing radiation, especially computed tomography (CT), and the highly negative downstream results of frequent, accumulated dosages: ionizing-produced cancers.
Addressing this trend, one likely to grow even more rapidly, the IAEA held a meeting in late April to propose the Smart Card method for documenting the accumulation of radiation dosage over an individual's lifetime; this, the organization said at the time, will be followed a report on the proposal in September and a follow-up meeting in January with a range of representatives from the "e-health" community and the various associations involved in the delivery of radiological procedures.
The need to track the accumulated doses of radiation a person is receiving is backed by authoritative concerns about the overall increase in radiological procedures worldwide.
IAEA cites the most recent estimates from the UN Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) that the estimated collective dose to the world's populations from medical diagnostic and dental X-ray examinations is 4 million man Sv a year (man Sv [Sievert] being a unit defining a dose to a population in biological terms). This is the result of an estimated 4 billion diagnostic X-ray exams overall an increase of more than 17% over the last 10 years in the collective global dose being delivered.
Drilling down into these basic statistics are two factors of special concern: the greater increase of dosages in the developed countries where X-ray machines are more prevalent and their use driven by robust reimbursement; and "defensive" medicine (this latter attracting increasing attention in the U.S.), thus adding to the total doses provided by new scanning procedures and, especially, via CT.
"During the last 100 years, improvements in technology have resulted in dose reductions for radiographic examinations by a factor more than 10-fold," the IAEA says, in a review of the April meeting. But this same reduction is not the case for CT, it says: "Since its introduction in 1972, CT technology has improved substantially, making it possible to obtain better quality CT examinations. However, patterns of use have been continuously changing, with increased utilization, and the percentage contribution of medical radiation dose from CT has continued to increase."
To produce its 3-D views, the average radiation dose of a CT scan is equal to about 500 chest X-rays, according to IAEA, and the precision of CT images is a factor encouraging increasing CT use. But the organization cites a November 2007 report in the New England Journal of Medicine, estimating that up to 50% of all scans done today are not justified medically.
An alternative terminology for the Smart Card is "Smart Access," IEAE says, because its intent is to provide consistency and greater unification of care for the patient "without affecting the diagnostic or clinical purpose."
It says that confidentiality issues are being handled by e-health groups and that the Smart Card project "simply aims to add radiation exposure information of the patient in e-health systems being developed by many countries" a statement rather problematical for the U.S., given its reluctant adoption of e-health systems and especially EMRs.
The organization is exploring several options for the system:
• A Smart Card containing a patient's information to which radiation dose data can be added, with or without images.
• A Smart Card used only as a "digital signature" used for accessing data online, the website serving as a "virtual" card.
• Radiation dose data placed on some other e-health record in a manner that tracks individual patient exposures over time, interoperability providing access from anywhere.
• For those countries without e-health records, something like "a radiation passport, somewhat like vaccination card."
IAEA defines one of its main responsibilities as establishing standards for radiation safety and providing for application of these standards. In 2001 it established a radiation protection program and launched an international action plan that involves a number of international organizations and professional societies in the field of radiology, medical physics, nuclear medicine, radiographers, radiation protection and radiation oncology.
It says the approach is not regulatory but rather is geared to promotion through training, provision of guidance, projects in Member States that assess radiation dose to patients and attempt dose reduction without compromising image quality.
It says that a "visible example" of its efforts is its web site on radiation protection of the patient http://rpop.iaea.org that site receiving a half-million hits per month.