FDA Taking Action to Reduce Cancer-Causing Radiation
from CT, Other Medical Imaging
CT, nuclear medicine, and fluoroscopic imaging save
lives but also pose risks from ionizing radiation that can cause caner
Feb. 9, 2010 In response to growing concern about
cancer risks being increased by radiation exposure from medical imaging
procedures, the Food and Drug Administration today announced an
initiative to reduce unnecessary radiation exposure from three types of
these procedures: computed tomography (CT), nuclear medicine studies,
and fluoroscopy.
Two reports in radiology journal: Epigenetics may
determine risk of low-dose radiation... and explain mechanisms of aging,
human development, and the origins of cancer, heart disease, mental
illness, etc.
These procedures are the greatest contributors to
total radiation exposure within the U.S. population and use much higher
radiation doses than other radiographic procedures, such as standard
X-rays, dental X-rays, and mammography.
CT, nuclear medicine, and fluoroscopic imaging have
led to early diagnosis of disease, improved treatment planning, and
image-guided therapies that help save lives every day. The FDA continues
to support a strong dialogue between patients and physicians over the
medical necessity and risk associated with these types of imaging
studies.
However, like all medical procedures, CT, nuclear
medicine, and fluoroscopy pose risks. These types of imaging exams
expose patients to ionizing radiation, a type of radiation that can
increase a persons lifetime cancer risk. Accidental exposure to very
high amounts of radiation also can cause injuries, such as skin burns,
hair loss and cataracts.
Health care decisions made by patients and
their physicians should include discussions of the medical need and
associated risks for each procedure.
The amount of radiation Americans are exposed to
from medical imaging has dramatically increased over the past 20 years,
said Jeffrey Shuren, M.D., J.D., director of the FDAs Center for
Devices and Radiological Health. The goal of FDAs initiative is to
support the benefits associated with medical imaging while minimizing
the risks.
While there is some disagreement over the extent of
the cancer risk associated with exposure to radiation from medical
imaging, there is broad agreement that steps can and should be taken to
reduce unnecessary radiation exposure.
For example, the radiation dose associated with a
CT abdomen scan is the same as the dose from approximately 400 chest
X-rays. In comparison, a dental X-ray calls for approximately one-half
the radiation dose of a chest X-ray. Both diagnostics serve important,
sometimes critical, public health needs.
Through the FDAs regulatory oversight of medical
imaging devices, such as CT scanners, and through collaboration with
other federal agencies and health care professional groups, the FDA is
advocating the adoption of two principles of radiation protection:
appropriate justification of the radiation procedure and optimization of
the radiation dose used during each procedure.
Working together, said Shuren, the FDA and other
organizations hope to help patients get the right imaging exam, at the
right time, with the right radiation dose.
The three-pronged initiative the FDA is announcing
will promote the safe use of medical imaging devices, support informed
clinical decision-making, and increase patient awareness of their own
exposure.
The FDA intends to issue targeted requirements for
manufacturers of CT and fluoroscopic devices to incorporate important
safeguards into the design of their machines to develop safer
technologies and to provide appropriate training to support safe use by
practitioners. The agency intends to hold a public meeting on March
30-31, 2010, to solicit input on what requirements to establish.
Examples could include a requirement that these
devices display, record, and report equipment settings and radiation
dose, an alert for users when the dose exceeds a diagnostic reference
level (the optimal dose for most patients), training for users, and a
requirement that devices be able to capture and transmit radiation dose
information to a patients electronic medical record and to national
dose registries.
In addition, the FDA and the Centers for Medicare
and Medicaid Services are collaborating to incorporate key quality
assurance practices into the mandatory accreditation and conditions of
participation survey processes for imaging facilities and hospitals.
These quality assurance practices will improve the quality of oversight
and promote the safe use of advanced imaging technologies in those
facilities.
The FDA recommends that health care professional
organizations continue to develop, in collaboration with the agency,
diagnostic radiation reference levels for medical imaging procedures,
and increase efforts to develop one or more national registries for
radiation doses.
A dose registry would pool data from many imaging
facilities nationwide, capturing dose information from a variety of
imaging studies. This registry will help define diagnostic reference
levels where they do not yet exist, validate levels that do exist, and
provide benchmarks for health care facilities to use in individual
imaging studies.
In a bid to empower patients and increase
awareness, the FDA is collaborating with other organizations to develop
and disseminate a patient medical imaging history card. This tool, which
will be available on the FDAs Web site, will allow patients to track
their own medical imaging history and share it with their physicians,
especially when it may not be included in their medical records.
Feb. 9, 2010 In response to growing concern about
cancer risks being increased by radiation exposure from medical imaging
procedures, the Food and Drug Administration today announced an
initiative to reduce unnecessary radiation exposure from three types of
these procedures: computed tomography (CT), nuclear medicine studies,
and fluoroscopy. 