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We Are Giving Ourselves Cancer

nytimes.com

131–140 of 167 posts

Re: We Are Giving Ourselves Cancer

#131
post #74

CT Scan doses vary wildly depending on the type of X-ray (chest, head, limb, etc.), the size of the person, and a lot of other things. The bigger the cross-section of the thing you put in a scanner, the greater the exposure. CT machines themselves also vary considerably. Newer machines are often more sensitive and employ better imaging software, so they can do their job while delivering a much smaller dose. Anyone wh…

While your comment as a whole is thoughtful and well written, I'm surprised to hear you say, "Medical imaging is not done very often..." Medical imaging is commonly overused, and its overuse is recognized as being one of the leading causes of certain types of cancer. For example, the original story explains... "In a 2011 report sponsored by Susan G. Komen, the Institute of Medicine concluded that radiation from medic…

Perhaps it varies wildly between countries. I've never heard of anyone I know having a CT scan, but I know of 3 MRI scans.

Re: We Are Giving Ourselves Cancer

#132
post #74

CT Scan doses vary wildly depending on the type of X-ray (chest, head, limb, etc.), the size of the person, and a lot of other things. The bigger the cross-section of the thing you put in a scanner, the greater the exposure. CT machines themselves also vary considerably. Newer machines are often more sensitive and employ better imaging software, so they can do their job while delivering a much smaller dose. Anyone wh…

While your comment as a whole is thoughtful and well written, I'm surprised to hear you say, "Medical imaging is not done very often..." Medical imaging is commonly overused, and its overuse is recognized as being one of the leading causes of certain types of cancer. For example, the original story explains... "In a 2011 report sponsored by Susan G. Komen, the Institute of Medicine concluded that radiation from medic…

This reminds me of an article about Komen and the abuse of mammograms http://www.nytimes.com/2013/04/28/magazine/our-feel-good-war...

Re: We Are Giving Ourselves Cancer

#133
post #73

When I worked with radiologists (at a PACS vendor, mainly selling to the military and the federal prisons), the radiologists and staff were exercising due care about minimizing radiation exposure from CTs. Personally, I don't care about regular x-rays, particularly digital ones, for any reasonable medical use. I get one every year or two as part of a checkup. CT and C-arm fluoroscopy scare me, as an educated person w…

There seems to be an unfounded fear of gastroscopy here in Austria so people often choose to get fluoroscopy during barium swallows (euphemistically called "stomach x-ray") for check-up on common issues like gastritis, ulcers, etc.

It always boggles the mind how doctors will habitually do fluoroscopy first (approx. 6mSv per session) when gastroscopy as a diagnostic tool is often 100% as effective while being mostly harmless and offering the option for a small biopsy for further diagnosis.

I've had gastroscopy multiple times myself, it's really no big deal and doesn't warrant getting a (general) anesthesia in my opinion but YMMV.

Re: We Are Giving Ourselves Cancer

#134
post #132

Earlier quoted context omitted.

While your comment as a whole is thoughtful and well written, I'm surprised to hear you say, "Medical imaging is not done very often..." Medical imaging is commonly overused, and its overuse is recognized as being one of the leading causes of certain types of cancer. For example, the original story explains... "In a 2011 report sponsored by Susan G. Komen, the Institute of Medicine concluded that radiation from medic…

This reminds me of an article about Komen and the abuse of mammograms http://www.nytimes.com/2013/04/28/magazine/our-feel-good-war...

That is a great, powerful, article. Thank you for posting the link.

> For an individual woman in her 50s, then, annual mammograms may catch breast cancer, but they reduce the risk of dying of the disease over the next 10 years by only .07 percentage points — from .53 percent to .46 percent. Reductions for women in their 40s are even smaller, from .35 percent to .3 percent.

Many people are going to be baffled by risk presented like this. Presenting the numbers differently is helpful to let people understand the risks.

"Imagine 10,000 women like you. Of those X will die from this disease. But if we take those same 10,000 women and give them mammograms we find that Y will die from the disease".

Sometimes X will be 2 and Y will be 1 (50% decrease in risk) or X will be 100 and Y will be 2 or X will be 100 and Y will be 99.

Presenting the numbers this way allows most people to understand the risks better.

Re: We Are Giving Ourselves Cancer

#135
post #86
post #74

CT Scan doses vary wildly depending on the type of X-ray (chest, head, limb, etc.), the size of the person, and a lot of other things. The bigger the cross-section of the thing you put in a scanner, the greater the exposure. CT machines themselves also vary considerably. Newer machines are often more sensitive and employ better imaging software, so they can do their job while delivering a much smaller dose. Anyone wh…

As someone now in Hong Kong about to fly back home to SF, I have always tried to schedule my flights so that I minimize my exposure to day time radiation. I guess I'm in the minority, but it's something to consider when taking international flights.

How do you travel to the airport, and did you factor in the risks of traveling at that different time?

Reducing a tiny risk in exchange for increasing an already large risk feels sub-optimal to me.

Re: We Are Giving Ourselves Cancer

#136

>One in 10 Americans undergo a CT scan every year, and many of them get more than one. For what?

For back pain? More than half of the people at some point in life develop some for back pain. It's scary so if you can afford a scan you get it. Of course there's nothing wrong and the pain goes away by itself in following months, usually after switching chair in which you spend most of your waking hours.

I can't imagine someone in the UK getting scans for lower-back back pain unless there was some clinical need for it.

The advice for most people would tend to be "lose weight, get exercise, check your beds and chairs; and carefully take paracetamol for the pain".

Re: We Are Giving Ourselves Cancer

#137

Earlier quoted context omitted.

I don't know why this was down voted; while in an elevator one is not supposed to use a cell phone, because of this effect. At least in the elevator at work there is a sign that says so. http://microwavenews.com/news-center/using-cell-phone-elevat...

That "in the elevator at work there is a sign that says so" is hardly evidence for anything. People use cellphones in elevators ALL the time, ALL around the world. Especially when continuing a conversation they had as they walked in the building, and for as long as the signal stays.

The evidence was in the link of my post: because of the Faraday cage/screening, part of the radio waves that the cellphone is emitting are reflected back into the elevator; the resulting strength of this fields exceeds the norms by an order of magnitude. this is considered to be within harmful range.

The parent poster mentions the same effect in the context of aeroplanes.

Re: We Are Giving Ourselves Cancer

#138
post #118

Earlier quoted context omitted.

I thought one is not supposed to use a cell phone in the elevator because it doesn't work because elevators are made out of ferrous metals and hence are effectively Faraday cages.

I can make and receive phone calls in lifts. It was weird the first few times. I'm in the UK if that makes any difference.

Could you make and receive phone calls in every lift you were in?

Re: We Are Giving Ourselves Cancer

#139
People who receive CT scans have a higher rate of cancer. This seems like a logical fallacy.

People who receive CT scans are more likely to get cancer. So CT scans must cause cancer.

The alternate hypothesis are that people who are more likely to develop cancer are more likely to have a CT scan. Given the tiny number involved here (in absolute number of people who develop cancer after having a CT scan), is it not possible that these people had a CT scan because of early symptoms of cancer?

Re: We Are Giving Ourselves Cancer

#140
post #131

Earlier quoted context omitted.

While your comment as a whole is thoughtful and well written, I'm surprised to hear you say, "Medical imaging is not done very often..." Medical imaging is commonly overused, and its overuse is recognized as being one of the leading causes of certain types of cancer. For example, the original story explains... "In a 2011 report sponsored by Susan G. Komen, the Institute of Medicine concluded that radiation from medic…

Perhaps it varies wildly between countries. I've never heard of anyone I know having a CT scan, but I know of 3 MRI scans.

MRI is very different from CT. CT use X-rays, which is an ionizing radiation. MRI uses a very strong magnetic field, and as far as we know it doesn’t increase the cancer rates.

The final images are quite similar in appearance (semi transparent films with a black background), but the underlying process is very different.

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