Reducing radiation risk from medical imaging

With the advancement of medical technology, use of improved imaging equipment like Computed Tomography (CT) scan, X-ray, CT Angiogram, heart scan have raised manifolds. But experts are concerned that the growth in imaging use could be exposing patients to too much radiation raising the risk of various adverse health effects especially deadly cancers.
Now a days, people are receiving far more diagnostic radiation than ever before. Among the imaging tools, CT scans are of particular concern because of the amount of ionising radiation they emit. Such radiation can damage cell in the body, giving rise to cancerous tumors. X-rays also emit ionising radiation, but at much lower doses. Magnetic resonance imaging (MRI) and ultrasound emit no radiation.
Radiation is known to cause cancer in humans. Radiation can also cause other adverse health effects, including genetic defects in the children of exposed parents or mental retardation in the children of mothers exposed during pregnancy. Unlike cancer, health effects from acute exposure to radiation usually appear quickly. There are also some acute health effects.
Children are at higher risk of complications from radiation exposure because their organs and tissues are very delicate and still developing. Cancers often take decades to emerge. The younger the patient (exposed to radiation) is, the greater the chance of developing cancer in his/her lifetime. That is why urgent efforts to reduce exposure especially in children due to imaging radiation is taken.
"How much radiation is too much" is still a matter for debate. Most people are exposed to 3 msv (radiation measured in millisieverts or msv) of radiation from natural sources over the course of a year. A standard chest X-ray emits about 0.1 msv, while a mammogram about 0.7 msv. A CT scan, on the other hand, can expose an individual to 10 to 20 msv in a matter of seconds.
Studies of atomic bomb survivors in Japan have shown an increase in cancers in the people farthest from the epicenter, who were exposed to between 5 msv and 150 msv during the bombings, with a mean dose of about 40 msv. That is comparable to the doses involved in just two or three CT scans.
Based on the Japanese data, researchers from Columbia University were able to estimate that 1.5 percent to 2 percent of cancers in the U.S. might be directly attributable to radiation from CT scans.
We have to reduce unnecessary use of radiation in diagnosis and treatment and ensure that technicians, equipment and techniques meet standards for minimising radiation exposure. Since any radiation exposure may carry some risk, it is necessary to decide whether the benefits of radiation justify its use. Health care providers must make the decision to use radiation on a case-by-case basis. Before receiving x-rays or any other type of medical treatment involving radiation exposure, you may discuss the need for and benefits of the procedure and its alternatives with your physician.
Experts suggest the following advices:
1.) Avoid unnecessary exposure to radiation.
2.) Persons working in radiation hazard areas should wear badges to measure their exposure levels.
3.) Protective shields should always be placed over the parts of the body not being treated or studied during x-ray imaging tests or radiation therapy.
Radiation has proven to be an effective way to diagnose disease at early stage, cure diseases and to help with controlling the growth of certain diseases like cancer. However, it must be used in moderation and with protected methods by health care providers and technicians.
There is still unawareness among our medical professionals and certainly they blame them who purchase imaging equipment for their clinic and then stood to profit from referring patients. Others blame the current malpractice environment that encourages over-testing to protect against patient lawsuits.
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