To be or not to be – that is the question: Whether ’tis nobler in the mind to suffer the slings and arrows of outrageous fortune, or to take arms against a sea of troubles and, by opposing, end them. Thus goes Hamlet’s soliloquy in Shakespeare’s famous play. In our case; to x-ray or not to x-ray – that is the question. Since initiating practice in 1986 patients continue to ask this very question. Some doctors utilize x-rays known as ionizing radiation as part of a routine examination. I choose not to use x-rays for routine diagnostic purposes and reserve exposure when absolutely clinically necessary.
According to the United States Environmental Protection Agency Fact Book (EPA-402-F-06-061) dated March 2007 relates x-rays ionizing radiation is the single largest source of man-made radiation exposure. The Fact Book further explains we humans are primarily exposed to natural radiation from the sun, cosmic rays, and naturally-occurring radioactive elements found in the earth’s crust. Cosmic rays from space include energetic protons, electrons, gamma rays, and x-rays. Radon gas, which emanates from the ground, comes from the decay of naturally-occurring radium and is a major source of radiation exposure. The primary radioactive elements found in the earth’s crust are uranium, thorium, and potassium, and their radioactive decay products. These elements emit alpha particles, beta particles, and gamma rays.
Adding to the naturally occurring radiation is that of manmade radiation which is radiation produced in devices, such as x-ray machines, and artificially produced radioisotopes made in a reactor or accelerator. This type of radiation is used in both medicine and industry. Main users of man-made radiation include: medical facilities, such as hospitals and pharmaceutical facilities; research and teaching institutions; nuclear reactors and their supporting facilities, such as uranium mills and fuel preparation plants; and federal facilities involved in nuclear weapons production.
Many of these facilities generate some radioactive waste, and some release a limited amount of radiation into the environment. Radioactive materials are used in consumer products, such as smoke detectors and self-illuminating exit signs. In addition to exposure from external sources, radiation exposure can occur internally from ingesting, inhaling, injecting, or absorbing radioactive materials. Both external and internal sources may irradiate the whole body or a portion of the body.
The amount of radiation exposure is expressed in a unit called millirem (mrem). In the United States, the average person is exposed to an effective dose equivalent of approximatly 360 mrem (whole-body exposure) per year from all sources (NCRP Report No. 93).
With all these sources of radiation in everyday life one may begin to ponder what the effect LONG TERM exposure may have on your health. Ponder you should because radiation affects people by depositing energy in body tissue, which can cause cell damage or cell death. In some cases there may be no noticeable effect. In other cases, the cell may survive but become abnormal, either temporarily or permanently. Additionally, an abnormal cell may become malignant. Both large and small doses of radiation can cause cellular damage. The extent of the damage depends upon the total amount of energy absorbed, the time period and dose rate of the exposure, and the particular organs exposed.
By damaging the genetic material (DNA) contained in the body’s cells, radiation can cause cancer. Damage to genetic material in reproductive cells can cause genetic mutations that can be passed on to future generations. In rare occurrences where there is a large amount of radiation exposure, sickness or even death can occur in a limited amount of hours or days.
Chronic exposure is continuous or intermittent exposure to low doses of radiation over a long period of time. With chronic exposure, there is a delay between the exposure and the observed health effect. These effects can include cancer and other health outcomes such as benign tumors, cataracts, and potentially harmful genetic effects
Acute exposure is exposure to a large, single dose of radiation, or a series of moderate doses received during a short period of time. Large acute doses can result from accidental or emergency exposures or from specific medical procedures (radiation therapy). For approved medical exposures, the benefit of the procedure may outweigh the risk from exposure.
In most cases, a large acute exposure to radiation causes both immediate and delayed effects. Delayed biological effects can include cataracts, temporary or permanent sterility, cancer, and harmful genetic effects. For humans and other mammals, acute exposure to the whole body, if large enough, can cause rapid development of radiation sickness, evidenced by gastrointestinal disorders, bacterial infections, hemorrhaging, anemia, loss of body fluids, and electrolyte imbalance. Extremely high dose of acute radiation exposure can result in death within a few hours, days, or weeks.
All people receive chronic exposure to background levels of radiation present in the environment. Many people also receive additional chronic exposures and relatively small acute exposures. For populations receiving such exposures, the primary concern is that radiation could increase the risk of cancer or harmful genetic effects.
The probability of a radiation-induced cancer or harmful genetic effects is related to the total amount of radiation accumulated by an individual. Based on current scientific evidence, any exposure to radiation can be harmful (e.g., can increase the risk of cancer); however, at very low exposures, the estimated increases in risk are very small. For this reason, cancer rates in populations receiving very low doses of excess radiation (doses of radiation above background) may be similar to the rates for average populations.
Evidence of injury from low or moderate doses of radiation may not show up for months or even years. For example, the minimum time period between the radiation exposure and the appearance of leukemia (latency period) is 2 years. For solid tumors, the latency period is more than 5 years. The types of effects and their probability of occurrence can depend on whether the exposure was chronic or acute. It should be noted that all of the long-term health effects associated with exposure to radiation can also be caused by other factors.
Getting back to the original question of to x-ray or not to x-ray; I treat each patient who seeks my care how I want to be treated. Feeling I receive enough background radiation I do not want the extra ionizing radiation from an x-rays unless absolutely necessary. During an examination encounter there are many tests designed to answer this very question.
Now a related article for your further enjoyment.
FDA Calls for Reducing Unnecessary Radiation Exposure from Three Devices by Janice Simmons, for HealthLeaders Media, February 9, 2010
A new three-pronged initiative to reduce unnecessary radiation exposure from three types of medical imaging procedures-computed tomography (CT), nuclear medicine studies, and fluoroscopy-was announced by the Food and Drug Administration (FDA) on Tuesday.
These combined procedures are considered the leading contributors to total radiation exposure in the U.S., because they use higher radiation doses than other radiographic procedures, such as standard X rays, dental X rays, and mammography, according to the FDA.
Of concern is exposing patients to ionizing radiation-a type of radiation that can increase an individual’s lifetime cancer risk. “The amount of radiation Americans are exposed to from medical imaging has dramatically increased over the past 20 years,” said Jeffrey Shuren, MD, JD, director of FDA’s Center for Devices and Radiological Health, in a statement. “The goal of FDA’s initiative is to support the benefits associated with medical imaging while minimizing the risks.”
As the first prong of the initiative, FDA said it intends to issue targeted requirements for manufacturers of CT and fluoroscopic devices. These requirements address safeguards in the design of their machines and provide appropriate training to support safe use by practitioners. FDA said it will hold a public meeting on March 30 31 to solicit input on what requirements to establish.
For the second part of the initiative, FDA and the Centers for Medicare and Medicaid Services will work together to incorporate key quality assurance practices into the mandatory accreditation and conditions of participation survey processes for imaging facilities and hospitals.
FDA is recommending that healthcare 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, and capture dose information from a variety of imaging studies.
For the third prong, FDA said it is working to empower patients and increase awareness by collaborating with other organizations to develop and disseminate a patient medical imaging history card. This tool, which will be made available on the FDA’s Web site, will permit 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.
The FDA action follows an announcement made a week earlier by the National Institutes of Health (NIH) that its physicians will begin recording radiation doses for patients in their medical records, according to an announcement in the recent issue of the Journal of the American College of Radiology.
A radiation reporting policy has been developed at the NIH Clinical Center in Bethesda, MD, that will be used in cooperation with major equipment vendors–beginning with exposures from CT and PET/CT.
All vendors that sell imaging equipment to the clinical center will be required to “provide a routine means for radiation dose exposure to be recorded in the electronic medical record,” said David A. Bluemke, MD, the study’s lead author and director of Radiology and Imaging Sciences at the Clinical Center.
In addition, radiology at NIH also will require that vendors ensure radiation exposure can be tracked by patients in their own personal health records. This approach is consistent with the American College of Radiology’s and Radiological Society of North America’s stated recommendation that “patients should keep a record of their X ray history.”