Category: Education

Mammograms, CT scans, X-rays: Assessing the risk of all that radiation

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An X-ray for knee pain. A CT scan for a head injury. Mammograms every other year, starting at age 50. Over a typical lifetime of radiation exposure from medical tests, a person can start to wonder: How much is too much?

There’s no formula for answering that, experts say, in part because the health effects of radiation don’t add up in a linear way. And while massive doses of radiation are known to be harmful, the small doses used in routine tests are usually safe, especially compared with other health-care choices people make without thinking twice.

“Radiation does have some risk,” says Russ Ritenour, a medical physicist at the Medical University of South Carolina in Charleston. “But it is important for medicine. And in most cases, the risk is quite small compared to the risk of taking too much Advil over your life and other things like that.”

Ionizing radiation – the type that can damage cells – is a daily fact of life even for people who never go to the doctor. Rocks and soil contain radioactive materials, which also appear in our food, our bones and the air we breathe. Cosmic rays barrage us with radiation from space, with higher doses at altitude and on airplanes.

Overall, a person in the United States gets an annual average of about 3 millisieverts (mSv) of background radiation. (Millisieverts are units that measure radiation absorbed by our bodies.)

Added exposure, totaling another 3 mSV each year for the average American, comes from such man-made sources as power plants that run on coal and nuclear fuel, and consumer products including TVs and computer screens. But most of the extra radiation we get comes from X-rays and CT scans, Ritenour says.

Most routine diagnostic tests emit extremely small amounts of radiation. A patient will get about 0.001 mSv from an arm X-ray, 0.01 mSv from a from a panoramic dental X-ray, 0.1 mSv from a chest X-ray and 0.4 mSv from a mammogram, according to Harvard Medical School. (Those estimates vary somewhat, depending on the source and on the specific device used, the size of the patient and other factors.)

CT scans, which take multiple X-rays to create cross-sectional images, deliver higher doses: 7 mSv for a chest CT, and 12 mSV for a full-body scan, according to the National Cancer Institute. Studies have found doses of 25 mSv or more from a PET/CT, an imaging test that requires ingesting a radioactive substance.

With the increasing availability and affordability of imaging technologies, people are getting more tests than they used to. Today, Americans receive more than 85 million CT scans each year, compared with 3 million per year in the 1980s.

Many of those tests may be excessive, argue some researchers, who have been trying to quantify the risks of our increasing use of ionizing radiation in medical imaging. A 2009 study by scientists at the National Cancer Institute estimated that 2 percent – or about 29,000 – of the 1.7 million cancers diagnosed in the United States in 2007 were caused by CT scans. In a 2004 study, researchers estimated that a 45-year-old who planned to get 30 annual full-body CT exams would have a nearly 2 percent lifetime risk of dying of cancer. Other studies are underway to clarify risks, including in children.

But evaluating an individual’s chances of experiencing a bad outcome from any given test or a combination of tests is tricky. Some of the most definitive data on radiation’s health effects come from long-term studies of tens of thousands of people who survived the atomic bombings of Hiroshima and Nagasaki in 1945. Sudden exposure to 1,000 mSv, those studies have found, increased the risk of getting cancer by 42 percent and increased the risk of dying of cancer by 5 percent.

Risks of secondary cancers also rise with the high doses of radiation used in some cancer treatment – a trade-off that often makes sense because doing nothing would be even riskier.

Evidence is murkier about health consequences from lower doses. The Food and Drug Administration estimates that 10 mSv of radiation, an amount typical for a CT of the abdomen, increases lifetime cancer risk by 1 in 2,000. But that calculation assumes that risks are proportional to dose, which has not been proved. Below 10 mSv, there is not enough good data to draw clear conclusions.

There is also no absolute number of scans that constitute a tipping point for health, Ritenour says, in part because our bodies have repair mechanisms that can fix cells damaged by radiation. So while every scan adds to the chances that a problem will occur, radiation doesn’t build up in the body. And damage doesn’t accumulate like water poured into a glass. Theoretically, he adds, 10 mammograms in one day would be riskier than one mammogram a year for 10 years.

“All you can really say is that there’s very little chance a problem can happen” at low doses, says Ritenour, who often consults with patients who have questions about radiation. “It is very unsatisfying in a way. You can’t say, ‘You will definitely have no problems.’ ”

Although health risks from most imaging tests are extremely small, fear can be hard for people to rationalize away. There is a one-in-a-million chance of getting cancer from a chest X-ray, Ritenour says, the same tiny chance of getting cancer from toxins in peanut butter.

Making decisions about diagnostic tests ultimately requires comparing their potential benefits with their potential harms. That balance can be easy to measure if someone has a broken leg or a bullet fragment lodged in their body. But decisions become more nuanced for tests such as mammograms, which catch breast cancers in some women but also produce false alarms that cause unnecessary anxiety and follow-up testing that entails even more radiation. Given the trade-offs, the U.S. Preventive Services Task Force offers evidenced-based advice about many screening tests, and those guidelines can be helpful starting points for conversations with your doctor.

Online calculators can also offer food for thought. When I entered my location, estimated miles traveled by airplane and other information into a tool maintained by the Nuclear Regulatory Commission , I learned that I absorb an estimated 318 millirems, or 3.18 mSv, of radiation each year. Each millirem, according to this government agency, equates to a 1.2-minute reduction in life span, the same accrued from eating 10 extra calories (assuming I’m overweight) or crossing the street three times. In other words, I am likely to die 4 1/2 hours sooner than I would if I could avoid radiation altogether.

While some researchers work to better understand and communicate the risks of radiation, others are refining technologies and procedures, adds Louis Wagner, a diagnostic medical physicist at McGovern Medical School at the University of Texas Health Science Center at Houston. And the field has come a long way.

For example, after studies found an elevated risk of breast cancer among women who had received X-rays for childhood scoliosis, experts say, many health centers switched from taking images from the front of the body to taking images from behind to reduce the cancer risk.

Technicians have made mistakes, such as using higher doses of radiation than needed during scans, and some mistakes have led to expensive legal cases, Wagner says. But those cases are rare. And most machines are now equipped with safety features to avoid overexposure.

“The profession has sought to make use of radiation very, very beneficial to patients with minimal and, I believe, unrecognizable risks,” Wagner says. “I want patients to know the medical profession is avidly pursuing better ways to use radiation to increase the benefits-to-risks ratio. I think good progress is being made.”

DeVos Ends Obama-Era Safeguards Aimed at Abuses by For-Profit Colleges

hospitalWASHINGTON — Education Secretary Betsy DeVos formally moved Friday to scrap a regulation that would have forced for-profit colleges to prove that the students they enroll are able to attain decent-paying jobs, the most drastic in a series of policy shifts that will free the scandal-scarred, for-profit sector from safeguards put in effect during the Obama era.

In a written announcement posted on its website, the Education Department laid out its plans to eliminate the so-called gainful employment rule, which sought to hold for-profit and career college programs accountable for graduating students with poor job prospects and overwhelming debt. The Obama-era rule would have revoked federal funding and access to financial aid for poor-performing schools.

After a 30-day comment period, the rule is expected to be eliminated July 1, 2019. Instead Ms. DeVos would provide students with more data about all of the nation’s higher education institutions — not just career and for-profit college programs — including debt, expected earnings after graduation, completion rates, program cost, accreditation and other measures.

“Students deserve useful and relevant data when making important decisions about their education post-high school,” Ms. DeVos said in a statement. “That’s why instead of targeting schools simply by their tax status, this administration is working to ensure students have transparent, meaningful information about all colleges and all programs. Our new approach will aid students across all sectors of higher education and improve accountability.”

But in rescinding the rule, the department is eradicating the most fearsome accountability measures — the loss of federal aid — for schools that promise to prepare students for specific careers but fail to prepare them for the job market, leaving taxpayers on the hook to pay back their taxpayer-backed loans.

The DeVos approach is reversing nearly a decade of efforts to create a tough accountability system for the largely unregulated for-profit sector of higher education. In recent years, large for-profit chains, which offer training for everything from automotive mechanics to cosmetology to cybersecurity, have collapsed under mountains of complaints and lawsuits for employing misleading and deceptive practices.

The implosions of ITT Technical Institute and Corinthian Colleges generated tens of thousands of complaints from student borrowers who said they were left with worthless degrees. The Obama administration encouraged the expansion of public community colleges as it forgave at least $450 million in taxpayer-funded student debt for for-profit graduates who could not find decent jobs with the degrees or certificates they had earned.

The regulations passed in the wake of those scandals remade the industry. Since 2010, when the Obama administration began deliberating the rules, more than 2,000 for-profit and career programs — nearly half — have closed, and the industry’s student population has dropped by more than 1.6 million, said Steve Gunderson, the president of Career Education Colleges and Universities, the for-profit industry’s trade association.

Even for-profit leaders concede the gainful employment rule has had its intended effect. Mr. Gunderson said that for-profit institutions had to adjust programming to be more affordable and responsive to the job markets.

READ MORE: https://www.nytimes.com/2018/08/10/us/politics/betsy-devos-for-profit-colleges.html?hp&action=click&pgtype=Homepage&clickSource=story-heading&module=first-column-region&region=top-news&WT.nav=top-news

AFRICA BY THE AFRICANS: Young Tastemakers Aim to Challenge Stereotypes

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The stereotypes about Africa/Africans are too many to list here. They’re mostly negative, myopic depictions that focus on war, famine, abject poverty, disease, and corruption. In other oversimplifications, Africans are written up as model immigrants, overachieving geniuses, or displaced chiefs moonlighting as gas station attendants. Outside of these caricatures, many Africans are going to work and school, voting in their local elections, and spending way too much time on Facebook. And they’re over the ignorance that has collectively miscast them. In response, a swelling movement of young Africans are launching concerted efforts to wrest the image of Africa from entities and interests that don’t promote a balanced understanding of the continent.

Among this group is South African professor Sean Jacobs who founded the incisive Africa is a Country, billing it as “the media blog that’s not about famine, Bono, or Barack Obama.” Ghanaians Sandra Appiah and Isaac O. Babu-Boateng launched Face 2 Face Africa Magazine to combat portrayals of Africa as pathological and troubled.

Likewise, Nigerian-American Enyinne Owunwanne started ecommerce boutique Heritage 1960 to promote what she says is “the best of the best, when it comes to African fashion, lifestyle and culture”. Fellow Nigerian-American Ngozi Odita initiated AFRIKA21 to broaden the conversation around what 21st century Africa really looks like, apart from the stereotypes. CONTINUE READING..

Gangsta’s paradise? U. of Arizona offers minor focusing on hip-hop

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Universities across the nation have offered courses on hip-hop culture for several years, but the University of Arizona has decided to take its program further, adding the subject as as a concentrationin its Africana Studies minor program. The decision, announced in December, is part of a trend to give serious academic study to the subject. And the new curriculum is bound to be a hit with Arizona students, said Alain-Philippe Durand, interim director of the Tucson school’s Africana Studies Program. The university has offered hip-hop courses since 2004. Last spring, a class on hip-hop cinema at the university filled up in a matter of hours with students emailing the teacher in an attempt to add the course. “Rap and hip-hop in general has become super-popular around the world,” Durand said. “The main reason for that is that it affects every single discipline and aspects of society.” News of the minor is exciting news, said Steven Pond, associate professor and chair of the Cornell University’s music department. Cornell is at the forefront of applying serious study to the hip-hop movement, touting the largest hip-hop collection of music recordings, rare fliers, artwork, photography and other memorabilia. “It’s a very good development and an exciting one … the idea of acknowledgment of the deep impact hip-hop has in many areas, across cultures,” Pond said.  “I think it’s a very positive development to see hip-hop enter the  academy, even if it’s a decade or even a generation late.” Arizona students hoping for an easy minor of just sitting back and listening to Jay-Z probably shouldn’t enroll, Durand said.

The curriculum goes beyond the stereotypical gang and drug cultures to examine the movement’s intersection with politics, marketing, fashion and other academic disciplines. Durand, author of “Black, Blanc, Beur: Rap Music and Hip-Hop Culture in the Francophone World,” said the idea to start a minor in the subject came to him after he noticed that he and his colleagues had expertise on hip-hop culture across various disciplines, such as film and music. They had enough courses among them to create a minor. Durand and his colleagues made their best pitch to university decision makers who obliged.

“The university itself is known for taking innovative steps like that,” Durand said, citing the university’s success in interplanetary exploration. “We break borders in astronomy and we break borders in hip-hop now.”