3 ms·

>Scanning is still fairly invasive (w.r.t. radiation/dosages). And in general, the better the resolution, the more damaging. This guy had MRI scans which don't

by mikecsh 12y ago

>Scanning is still fairly invasive (w.r.t. radiation/dosages). And in general, the better the resolution, the more damaging. This guy had MRI scans which don't rely on ionising radiation and have no known adverse effects. >everyone has all sorts of little cancerous growths that are entirely benign When discussing tumours, cancerous and benign mean different things. You cannot have a benign cancerous growth. I think the main reason people aren't scanned routinely is due to the enormous cost of the scanning and the data analysis that currently relies on physicians for interpretation. My personal view is that with ever decreasing costs of MRI and improvements in computer vision and diagnostic algorithms, this could become a viable process in the future. As for not over-treating, that is a physician led decision - just because there is an anomaly on the scan does not mean that it will be removed or even necessarily treated at all.

throwaway47385 12y ago
> This guy had MRI scans which don't rely on ionising radiation and have no known adverse effects. http://www.ncbi.nlm.nih.gov/pubmed/21412810 http://www.ncbi.nlm.nih.gov/pubmed/21412810 Also, the price of a single scan is measured in thousands of dollars.
- sghodas 12y ago
  I skimmed that study, but it looks like all the samples they tested came from the same guy, and they didn't actually test putting people in MRIs.
  - throwaway47385 12y ago
    Yes, the authors did base their paper on in vitro tests from a single individual. Another group attempted to reproduce the results of Lee, et al by performing a similar in vitro experiment, but failed to detect any DNA damage.[1] Nevertheless, in an article commentary published by the European Society of Cardiology [2], DNA damage was detected in an in vivo study of Cardiac MR (CMR) imaging, and a precautionary approach to MR imaging is recommended. They admit, though, that the study could not differentiate between the effects of the contrast agent used in CMR, and the effects MR imaging alone. [1] http://www.ncbi.nlm.nih.gov/pubmed/23679232 http://www.ncbi.nlm.nih.gov/pubmed/23679232 [2] http://eurheartj.oxfordjournals.org/content/34/30/2337 http://eurheartj.oxfordjournals.org/content/34/30/2337
a_c_s 12y ago
While you are technically correct, it appears you've missed the point: being able to detect tumors better doesn't improve lifespan if we end up aggressively treating benign ones. This isn't a theoretical problem, rather one we are seeing right now. Look at thyroid cancer: detection and treatment rates are much higher than they used to be but the death rate has remained steady. Source: http://www.nytimes.com/2014/11/06/health/study-warns-against-overdiagnosis-of-thyroid-cancer.html?_r=0 http://www.nytimes.com/2014/11/06/health/study-warns-against...
- mikecsh 12y ago
  Actually, I addressed this point in my original comment: > As for not over-treating, that is a physician led decision - just because there is an anomaly on the scan does not mean that it will be removed or even necessarily treated at all. Perhaps I wasn't clear. I am saying that having cheaper, better scans with computer aided analysis is likely to be beneficial. I am not saying that every anomaly detected requires treatment. Treatment decisions are influenced by imaging but are not enforced by them.
DanBC 12y ago
> I think the main reason people aren't scanned routinely is due to the enormous cost of the scanning and the data analysis that currently relies on physicians for interpretation. The main reason is that doctors and regulators warn against it because, as patent says, people are chock full of scars and lumps and stuff that shows on scans but that is not in anyway harmful. http://news.bbc.co.uk/1/hi/health/7150583.stm http://news.bbc.co.uk/1/hi/health/7150583.stm > "If 100,000 people undergo a CT scan every five years from age 40 to 70 years...then the estimated impact is approximately 240 excess fatalities." Although that's talking about CT, not MRI, scans.
- mikecsh 12y ago
  Yes, my comments are limited to MRI. A full-body CT scan is a very large dose of radiation.

by mikecsh 12y ago

throwaway47385 12y ago

> This guy had MRI scans which don't rely on ionising radiation and have no known adverse effects. http://www.ncbi.nlm.nih.gov/pubmed/21412810 http://www.ncbi.nlm.nih.gov/pubmed/21412810 Also, the price of a single scan is measured in thousands of dollars.

sghodas 12y ago
I skimmed that study, but it looks like all the samples they tested came from the same guy, and they didn't actually test putting people in MRIs.
- throwaway47385 12y ago
  Yes, the authors did base their paper on in vitro tests from a single individual. Another group attempted to reproduce the results of Lee, et al by performing a similar in vitro experiment, but failed to detect any DNA damage.[1] Nevertheless, in an article commentary published by the European Society of Cardiology [2], DNA damage was detected in an in vivo study of Cardiac MR (CMR) imaging, and a precautionary approach to MR imaging is recommended. They admit, though, that the study could not differentiate between the effects of the contrast agent used in CMR, and the effects MR imaging alone. [1] http://www.ncbi.nlm.nih.gov/pubmed/23679232 http://www.ncbi.nlm.nih.gov/pubmed/23679232 [2] http://eurheartj.oxfordjournals.org/content/34/30/2337 http://eurheartj.oxfordjournals.org/content/34/30/2337

a_c_s 12y ago

While you are technically correct, it appears you've missed the point: being able to detect tumors better doesn't improve lifespan if we end up aggressively treating benign ones. This isn't a theoretical problem, rather one we are seeing right now. Look at thyroid cancer: detection and treatment rates are much higher than they used to be but the death rate has remained steady. Source: http://www.nytimes.com/2014/11/06/health/study-warns-against-overdiagnosis-of-thyroid-cancer.html?_r=0 http://www.nytimes.com/2014/11/06/health/study-warns-against...

mikecsh 12y ago
Actually, I addressed this point in my original comment: > As for not over-treating, that is a physician led decision - just because there is an anomaly on the scan does not mean that it will be removed or even necessarily treated at all. Perhaps I wasn't clear. I am saying that having cheaper, better scans with computer aided analysis is likely to be beneficial. I am not saying that every anomaly detected requires treatment. Treatment decisions are influenced by imaging but are not enforced by them.

DanBC 12y ago

> I think the main reason people aren't scanned routinely is due to the enormous cost of the scanning and the data analysis that currently relies on physicians for interpretation. The main reason is that doctors and regulators warn against it because, as patent says, people are chock full of scars and lumps and stuff that shows on scans but that is not in anyway harmful. http://news.bbc.co.uk/1/hi/health/7150583.stm http://news.bbc.co.uk/1/hi/health/7150583.stm > "If 100,000 people undergo a CT scan every five years from age 40 to 70 years...then the estimated impact is approximately 240 excess fatalities." Although that's talking about CT, not MRI, scans.

mikecsh 12y ago
Yes, my comments are limited to MRI. A full-body CT scan is a very large dose of radiation.