Overuse, Overdose, Overdiagnosis… Overreaction?
Imaging Department, Sime Darby Specialist Centre Megah
Sdn. Bhd., Petaling Jaya, Malaysia
When x-rays were first discovered, the harmful effects of
radiation had to be manifest in the early users before they were known. Today,
radiation protection and safety have been established and the effects of
radiation, as well as its risks, are known. Even so, medical radiation, in
particular the growth in the use of computed tomography (CT), has resulted in
soaring radiation doses received by the population in general. Inappropriate
use has resulted in overuse, overdose and, perhaps, overdiagnosis, especially
when used in screening. In the quest to control and curb the use of procedures
involving radiation, however, we must be careful not to provoke a pandemic of
irrational fear of radiation. Overreaction to the overuse and overdose of radiation
might deter patients from life-saving procedures. © 2010 Biomedical
Imaging and Intervention Journal. All rights reserved.
Keywords: Radiation risks, medical radiation, computed
tomography, radiation overuse, radiation overdose
There has been an escalation of radiation dose for medical
purposes especially with the increasing use of Computed Tomography (CT)
scanners , and hybrid modalities such as Positron Emission Tomography-CT.
Heart scans for coronary artery calcifications began with the advent of the
electron beam CT scanner. Today, very fast multislice or dual-source CT
scanners have been added to the armamentarium to scan the heart for
calcifications as well as for CT angiograms. As new indications gain
acceptance, there seems to be nothing that the multislice CT scanner cannot do,
particularly with further developments and the use of nano-technology such as
the gold nanoprobes  for CT molecular imaging. The trend in Malaysia is similar, with the frequency of CT scans and interventional cardiac procedures
showing a marked increase over the years .
With inappropriate use and overuse, comes overdiagnosed
conditions which may never have become clinically significant if not discovered
during screening procedures. Population-based screening mammograms have come
under great scrutiny where overdiagnosis might have caused more harm than
benefit [4, 5].
It is ironic, but because radiation is invisible, its
potential danger is often forgotten. The discovery of the mysterious, invisible
x-rays in 1895 by Wilhelm Conrad Roentgen; radioactivity in 1896 by Henri
Becquerel; and radium by Marie Curie brought on a very exciting period.
New-found uses of x-rays were hailed and marketed. No one knew it could cause
harm, until the dangers became apparent.
That was then. Now, radiation has been well-investigated
as a cause for sickness. Radiation protection was born, and radiation safety
measures made this discipline harmless for its practitioners… or so we thought!
Perhaps equipment has become so safe to the operators/radiologic technologists,
that the potential radiation risks to patients are forgotten.
While physicians who are not radiologists or radiation
oncologists can plead ignorance to the fact that radiation has potential risks,
what can the latter say in their defence? In our training as radiologists, the
principle of ALARA was the mantra – As Low As Reasonably Achievable. We were
reminded to ensure that investigations or procedures were justified, and if so,
determine the best tool to use, and to consider foremost, a tool that did not
require ionising radiation (such as the ultrasound). We had to ensure that the
procedure was optimised to answer the clinical question while minimising the
radiation dose and still obtaining diagnostic information. After all, we
studied the effects of radiation, did we not?
A breakdown in communication between referring physicians
and radiologists or nuclear medicine physicians would have contributed to the
increase in inappropriate, unjustified procedures in an environment of
increasing workload and time pressure. Fear of litigation tends to reduce
reliance on pure clinical acumen. Another contributing factor is that,
increasingly, practitioners using ionising radiation are no longer just
radiologists. Examples would be cardiologists and neurologists using (or
self-referring) CT and Magnetic Resonance (MR) scans, as well as performing
fluoroscopic-guided interventions. Then, there is also pressure from the
patient as the Internet has made information – or misinformation – readily
available to them.
The digital era came with exciting changes in the way we
work: efficiency was increased, workflow improved, and throughput increased;
yet, the lack of need for printed films (cost issues and reject films serve as
constant reminders) and digital manipulation of images may have spurred
radiologists and radiologic technicians (or radiographers) to slack off on
diligent monitoring of radiation doses while performing procedures . Dose
creep is insidious but it is a real problem. Even if doses are monitored and
reported by the equipment software, they often go unnoticed. This is one reason
that lethal radiation therapy can be delivered “accidentally” .
In the last few years, journal publications and media
reports have highlighted the inappropriate use of our diagnostic tools , and
errors leading to lethal overdoses in radiation therapy. Hopefully, these
reports will act as an impetus to improve healthcare delivery in these areas.
The Food and Drug Administration of the USA  and the US Congress  have
come into the picture, with hearings on medical radiation exposure in the first
quarter of 2010. Recommendations to record radiation dose for patients over
their lifetime would provide an estimate of the cumulative dose. This would
guide radiologists and physicians to weigh the radiation risks with respect to
cancer induction. It is now public knowledge that acute excessive radiation
causing skin burns, erythema or hair loss may be seen in interventional
procedures under fluoroscopic guidance or even perfusion CT of the brain. Are
we overreacting to this “crisis”? Is this crisis real or perceived?
Warnings of the rising radiation dose and overuse of
radiation are not new. The National Council on Radiation Protection and Measurements
in 2007 reported that clinicians, including radiologists, were not cognisant of
radiation exposure risks  and that hybrid modalities  such as the
PET-CT would result in even higher patient radiation doses. The International
Commission on Radiological Protection  has published reports, such as
diagnostic reference levels, recommended dose limits and the biological effects
of ionising radiation (BEIR). The Alliance of Radiation Safety in Paediatric
Imaging developed the Image Gently Campaign  in 2007, and since then, there
has been growing support worldwide. I am happy to state that the College of
Radiology, Academy of Medicine of Malaysia is a member of this alliance;
however, more measures are definitely needed to ensure that every member
“lives, eats and thinks” radiation protection.
With reference to CT scanners, vendors, inventors and
radiologists have collaborated to help develop protocols and to produce
equipment that delivers less radiation or has software incorporated to set off
an alarm to warn the users. However, machines or software cannot replace
responsible, conscientious and justified use by the equipment operators,
radiologists and referring physicians.
Other methods are being explored and tested, such as
implementing software for decision–making , using appropriateness criteria
developed by the American College of Radiology , using legislation to curb
self-referrals or obtaining informed consent for every procedure . In 2009,
a radiology resident developed a software programme  for the iPhone which
helps calculate doses; although the dose calculation may not directly translate
into risks in such a simple manner, it serves as a guide that may come in
useful for the referring physician and the patient. It also keeps track of
radiation doses from procedures.
Time will tell if all the media hype and attention
garnered by medical radiation will backfire in some way, unless measures are
implemented carefully. The publicity and education must be communicated in ways
that the layperson can understand. Otherwise, we might provoke a pandemic of
irrational fear of radiation. There can be no doubt that imaging and
image-guided interventions have saved many lives, perhaps more lives than they
may harm. It is difficult to quantify radiation risk and to extrapolate it
directly to harm when it comes to those involving mutations and cancer
induction. Radiation risk is influenced by many factors, such as sex, age,
organ involved and underlying genetic factors. In addition, it is not just
cancer that may be induced; there are other adverse health effects to be
considered as well.
While we are “battering” ourselves over the excessive
doses of radiation applied in diagnostics or therapeutic, there are others out
there, waiting to pounce on an opportunity to market their “alternative”
imaging solutions. The screening boom for wellness has been a double-edged
sword. Non-proven methods for cancer prevention have emerged, touting amazingly
safe procedures that can detect signs of cancer way before cancer appears,
while assuring no radiation, no pain and no side effects, or promoting the use
of supplements to prevent cancers from developing. Will we be creating another
problem by over-publicising the radiation risks of medical procedures and
Therefore, a cost-benefit-risk analysis and a balanced
perspective is needed in all measures that are being taken to control medical
radiation. Although there are many potential solutions, everyone must take
responsibility to ensure careful implementation that is tailored for various
institutions, cultures and countries. The best approach is to ask ourselves:
just because a tool is there, must we use it? One size does not fit all, and no
matter what, the patient's interest comes first.
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|Received 2 April 2010; accepted 28 April 2010
Correspondence: Imaging Department, Sime Darby Specialist Centre Megah Sdn. Bhd., Petaling Jaya, Malaysia. E-mail: email@example.com (Evelyn Ho).
Please cite as: Ho ELM,
Overuse, Overdose, Overdiagnosis… Overreaction?, Biomed Imaging Interv J 2010; 6(3):e8