Japan Aerospace Exploration Agency astronaut Aki Hoshide makes a space walk outside the International Space Station in 2012.
April 2, 2014 Risks to astronauts on extended missions include vision impairment, weakened bones and radiation exposure. There are also psychological risks from facing danger while being stuck inside a small craft.
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CT scans are valuable for finding cancers, but deliver a lot of radiation in the process. That's an especially big concern for children.
February 20, 2014 CT scans are good at finding cancer, but their hefty dose of X-rays increases the risk of future cancers. Children are especially vulnerable. A new form of MRI can find tumors without radiation.
Use of CT scans has doubled for children under five and tripled for older children.
June 11, 2013 Children are getting too many CT scans, a study says, and that's boosting their risk of cancer later on. Parents can ask for alternatives like ultrasound and MRI or ask for CT scans that use less radiation.
May 30, 2013 The dose of radiation an astronaut would experience on a trip to Mars is higher than the annual limit set for workers at nuclear power plants. But Mars enthusiasts say the radiation threat isn't high enough to cancel the trip.
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Radiation therapist Jean Etienne holds a range compensator, which shapes the depth to which the proton beam enters a patient's body to target a tumor.
October 29, 2012 Proton therapy can be targeted much more precisely than regular radiation. The hope is that it translates into far fewer side effects, such as impotence and incontinence. But it also costs twice as much as regular radiation. And there's no proof it's more effective — it could potentially be worse, say some radiation experts.
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Easy does it on the X-ray doses for kids.
May 9, 2012 The Food and Drug Administration is proposing that manufacturers of X-ray machines and CT scanners do more to protect children from radiation exposure. If companies don't take steps to limit X-ray doses, the agency may require a label on their new equipment recommending it not be used on children.
This illustration shows a device made by MammoSite used to deliver targeted doses of radiation as part of brachytherapy.
Courtesy Radiological Society of North America
April 9, 2012 The use of brachytherapy is gaining popularity, but some medical experts worry that not enough research has been done to make sure it works as well as the traditional approach to radiation.
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A sign at Chicago's Midway Airport informs travelers about the millimeter wave scanners used to screen passengers.
Scott Olson/Getty Images
July 21, 2011 Over the next few months the Transportation Security Administration says it will retrofit 241 of its 488 airport scanners with software that's so unrevealing anybody, including passengers, can look at the pictures.
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