Dental X-Rays Linked To Common Brain Tumor

[ElNono]

"A new study suggests people who had certain kinds of dental X-rays in the past may be at an increased risk for meningioma (http://www.ibtimes.com/articles/326037/20120410/meningioma-dental-x-rays-common-brain-tumor.htm), the most commonly diagnosed brain tumor in the U.S. Dr. Elizabeth Klaus, the study's lead author and a professor at the Yale School of Medicine, discovered that dental X-rays are the most common source of exposure to ionizing radiation — which has been linked to meningiomas in the past — and that those diagnosed with meningiomas were more than twice as likely as a comparison group to report ever having had bitewing images taken. And regardless of the age when the bitewings were taken, those who had them yearly or more frequently were at between 40 percent and 90 percent higher risk at all ages to be diagnosed with a brain tumor."

[Agloco]

The findings cannot prove that radiation from the imaging caused the tumors, and the results are based on people who were likely exposed to higher levels of radiation during dental X-rays than most are today.

"It's likely that the exposure association we're seeing here is past exposure, and past exposure levels were much higher," said Dr. Elizabeth Claus, the study's lead author and a professor at the Yale School of Medicine in New Haven, Connecticut.

This passage in particular deserves a bit more scrutiny. The biggest problem is that at diagnostic energies and techniques, we are imparting dose which results in stochastic tissue effects. Definitive radiobiologic determination of tissue response to ionizing radiation requires the presence of deterministic effects, which we don't have here.

Further confounding the issue is that the cellular response to ionizing radiation is time and energy dependent. Were the employed imaging techniques consistent? Neural tissue is fairly radioresistant in general making any induced biologic effect more dependent on dose rate rather than total dose. Herein lies another problem, one of threshing out the exact radiation quality those old machines were imparting.

Lastly, a footnote about dental imaging in general: Dental imaging is largely unregulated. That is, unlike conventional radiology and radiation oncology, the dentists and techs are not beholden to the same radiation quality controls and dose limitation practices that your friendly physicists are there to enforce. Its quite scary. Yes, your dentist and their techs are free to use whatever techniques and number of exposures they feel are necessary to get the images they need (within machine limits of course, but they are still adjustable). Machine QA is not required to be done by a licensed physicist either.

At any rate, just some FYI. Back to proton vault designs.

[DarrinS]

To put that in perspective, Dr. Paul Pharoah, a cancer researcher at the University of Cambridge said in a statement the results would mean an increase in lifetime risk of intracranial meningioma in the U.K. from 15 out of every 10,000 people to 22 in 10,000 people.

Holy shit! An increase of 0.0005%!!!!!!?

[ElNono]

This passage in particular deserves a bit more scrutiny. The biggest problem is that at diagnostic energies and techniques, we are imparting dose which results in stochastic tissue effects. Definitive radiobiologic determination of tissue response to ionizing radiation requires the presence of deterministic effects, which we don't have here.

Further confounding the issue is that the cellular response to ionizing radiation is time and energy dependent. Were the employed imaging techniques consistent? Neural tissue is fairly radioresistant in general making any induced biologic effect more dependent on dose rate rather than total dose. Herein lies another problem, one of threshing out the exact radiation quality those old machines were imparting.

Lastly, a footnote about dental imaging in general: Dental imaging is largely unregulated. That is, unlike conventional radiology and radiation oncology, the dentists and techs are not beholden to the same radiation quality controls and dose limitation practices that your friendly physicists are there to enforce. Its quite scary. Yes, your dentist and their techs are free to use whatever techniques and number of exposures they feel are necessary to get the images they need (within machine limits of course, but they are still adjustable). Machine QA is not required to be done by a licensed physicist either.

At any rate, just some FYI. Back to proton vault designs.

At this day and age I can't think you can't have a set of rules that regulate the electronics on machines not to dispense harmful dosages or detect miscalibration. There's no technology barrier here.


Holy shit! An increase of 0.0005%!!!!!!?

Actually, that's 0.07%. But do you want to be one of those 7 people with cancer? And the better question: can we avoid it?

[greyforest]

Many cancers are very hard to link to a cause due to the nature of the disease. They can take years, even decades to develop after the initial trigger.

Dental x-rays are taken once every couple of years or so. I'd be much more worried about the scanners in all of our airports running constantly with millions of people adjacent to them.

[Spurminator]

Holy shit! An increase of 0.0005%!!!!!!?

lol @ this from Mr. Widespread Voter Fraud.

[Agloco]

At this day and age I can't think you can't have a set of rules that regulate the electronics on machines not to dispense harmful dosages or detect miscalibration. There's no technology barrier here.

Couple of double negatives in there, but I assume you meant that you can't imagine machines that do not fail safes? The answer is they do, but are easily overridden with the click of a mouse or with a "research" key. Usually the operator gets a benign message such as:

"Warning, you are setting this machine outputs above the recommended manufacturer presets. Proceed?"

Not:

"Continuing with these inputs will result in a twofold increase in the lifetime risk for cancer in this patient, and exceeds the ICRP limits. Proceed?"

Obviously if I, or some with my background, were at the controls we would abort or reset the machine even with the first message. A dental tech? A dentist? Hell, a radiologist? Odds are much lower. Remote actually, since the image must be obtained for care to proceed right?

Additionally, the scans can be repeated.......ad-infinitum. This is where the danger really multiplies. Very few people outside of radiation protection experts really understand or appreciate the risks involved with CT or x-ray, much less with repeating those scans. I'd be willing to be that most if not all of those cases were due to "re-scanning" multiple times.

Detection of miscalibrations is not something that's done for each scan. It's part of daily QA that physicists perform in radiology and radiation oncology departments, usually in the morning before the machines are used clinically. Machine outputs are tested using ionization chambers and the outputs are verified/compared with those on the treatment monitors.

Keeping a dosimeter in the FOV or treatment field perturbs it (think of Schrodingers cat here). This leads to dose inaccuracies and inhomogeneities in the case of a linear accelerator or gamma knife, etc. It degrades image quality in the case of a CT or x-ray.


Actually, that's 0.07%. But do you want to be one of those 7 people with cancer? And the better question: can we avoid it?

We'd need a non-ionizing imaging modality that offers the same contrast as ionizing modalities between materials with higher and lower Z. Do that, and the case is closed. You're also set for life. :toast

[Agloco]

Holy shit! An increase of 0.0005%!!!!!!?


Damn. You really didn't even try to fact check this.

Damn. You really didn't did you?

smh.

[DarrinS]

Actually, that's 0.07%. But do you want to be one of those 7 people with cancer? And the better question: can we avoid it?

My bad.

[ElNono]

Couple of double negatives in there, but I assume you meant that you can't imagine machines that do not fail safes? The answer is they do, but are easily overridden with the click of a mouse or with a "research" key. Usually the operator gets a benign message such as:

"Warning, you are setting this machine outputs above the recommended manufacturer presets. Proceed?"

Not:

"Continuing with these inputs will result in a twofold increase in the lifetime risk for cancer in this patient, and exceeds the ICRP limits. Proceed?"

Obviously if I, or some with my background, were at the controls we would abort or reset the machine even with the first message. A dental tech? A dentist? Hell, a radiologist? Odds are much lower. Remote actually, since the image must be obtained for care to proceed right?

Additionally, the scans can be repeated.......ad-infinitum. This is where the danger really multiplies. Very few people outside of radiation protection experts really understand or appreciate the risks involved with CT or x-ray, much less with repeating those scans. I'd be willing to be that most if not all of those cases were due to "re-scanning" multiple times.

Detection of miscalibrations is not something that's done for each scan. It's part of daily QA that physicists perform in radiology and radiation oncology departments, usually in the morning before the machines are used clinically. Machine outputs are tested using ionization chambers and the outputs are verified/compared with those on the treatment monitors.

Keeping a dosimeter in the FOV or treatment field perturbs it (think of Schrodingers cat here). This leads to dose inaccuracies and inhomogeneities in the case of a linear accelerator or gamma knife, etc. It degrades image quality in the case of a CT or x-ray.

We'd need a non-ionizing imaging modality that offers the same contrast as ionizing modalities between materials with higher and lower Z. Do that, and the case is closed. You're also set for life. :toast

I guess I didn't express myself correctly. What I mean is that there's no reason in this day and age for technology to be used so that it enforces certain regulations.

That current tech has easy bypass features doesn't mean that you can't take those away, from a tech standpoint. Hope that's more clear :D

[Agloco]

I guess I didn't express myself correctly. What I mean is that there's no reason in this day and age for technology to be used so that it enforces certain regulations.

That current tech has easy bypass features doesn't mean that you can't take those away, from a tech standpoint. Hope that's more clear :D

Ah, ok. I misunderstood. Disregard then.:toast

[mouse]

This topic reminds me of when Milli Vanilli got busted for lip syncing someone else's songs. Looks like Agloco's chickens have come home to roost.


Sad thing is instead of a modest intelligent reply he goes deeper in the pit if denile and supports his deadly radiation God even more.

Very disturbing.

[Wild Cobra]

This topic reminds me of when Milli Vanilli got busted for lip syncing someone else's songs. Looks like Agloco's chickens have come home to roost.


Sad thing is instead of a modest intelligent reply he goes deeper in the pit if denile and supports his deadly radiation God even more.

Very disturbing.

I thought it was a good answer.

I'm curious Mouse...

Do you avoid all potassium in your lifestyle since it's radioactive? Or just Bananas?

Did you know that Potassium deficiency is a cause for erectile dysfunction?

[mouse]

The Banana card has been pulled already numerous times how you can be so closed minded as to equate eating a Banana to millions of brain tumors is beyond human comprehension.

[Wild Cobra]

The Banana card has been pulled already numerous times how you can be so closed minded as to equate eating a Banana to millions of brain tumors is beyond human comprehension.
Maybe I'm wrong. It wouldn't be the first time, but isn't it you who stated does not eat bananas because of the radioactive potassium in them?

Now again, I may be wrong but I don't think you can get radiation free potassium anywhere, unless you pay some really big bux for manufactured purity.

Potassium is a necessary element for our bodies. So... how can you maintain any level of proper health if you avoid potassium?

[Wild Cobra]

Wiki: Hypokalemia (http://en.wikipedia.org/wiki/Hypokalemia)

[mouse]

When your serious to talk about the effects of radiation exposure w/o bringing up your Ancestors diet feel free to let me know.

[Wild Cobra]

Am I right or wrong about you bringing up a big stink about bananas?

[TDMVPDPOY]

man made machines increasing the selective selection process, nothing wrong with that

more kents die, the merrier

[mouse]

Am I right or wrong ?


on this subject, your Dead wrong.

[Wild Cobra]

on this subject, your Dead wrong.
OK, then I'm wrong.

Was that so hard?

Who was it in the Tsunami thread complaining about the radiation in bananas. Do you remember? I did think it was you. For that, I'm sorry.

[Agloco]

This topic reminds me of when Milli Vanilli got busted for lip syncing someone else's songs. Looks like Agloco's chickens have come home to roost.


Sad thing is instead of a modest intelligent reply he goes deeper in the pit if denile and supports his deadly radiation God even more.

Very disturbing.

Fear of the unknown. Its natural tbh.

fwiw, I was pointing out some of the dangers posed by unregulated medical imaging. You're far too busy trying to make me out to be some sort of callous profiteer to realize it though.


Looks like Agloco's chickens have come home to roost.

Elaborate for us slower-witted minds please.

[Agloco]

Who was it in the Tsunami thread complaining about the radiation in bananas. Do you remember? I did think it was you. For that, I'm sorry.

All the while he's too wrapped up in the banana danger to realize that he's irradiating himself with the very same isotope each and every day. smh.

[Wild Cobra]

All the while he's too wrapped up in the banana danger to realize that he's irradiating himself with the very same isotope each and every day. smh.

At least he means well.