So we think that we can get to that future where people pick MRI based on application and not cost or availability.
I've wondered why there are no MRIs using high temperature super conductors yet, it seems like such an obvious way to cut costs (as you don't need the extreme cryogenics).
High T super conductors will be very interesting in the next decade, I think, but right now there are a few issues that I'm aware of:
1) The high T super conductors are almost all crystals, not ductile metals. This means it can be very difficult to form coils or other structures out of them.
2) High T super conductors generally can't withstand as high a magnetic field as the lower T super conductors. I'm not sure how practical a concern this is for MRI.
The benefit of High T super conductors is that you switch from using liquid helium as your cryogen to liquid nitrogen. This is a major simplification, but we're not all the way to room temp yet, unfortunately.
I'm not in the medical field, but I really believe the future of cancer medicine will strongly lean towards prevention and early detection, as opposed to just cure.
After a bit of reseach I discovered it's a false promise. A lot of people have benign lumps and growths they can carry around for a lifetime without any trouble, and while MRIs are quite safe biopsies are not. If you don't have a reason to think you might have cancer, i.e. the MRI is a screening tool and not being used for a diagnosis, the very small chance you'll die of complications from unnecessary biopsies outweighs the very small chance you'll save your life by discovering a treatable malignant growth.
At least, that was the state of the art 7-8 years ago.
This always seemed to me a terrible indictment of how medicine is practiced. Knowing that, do you have to chase down every lump your screening finds? Can you not consider the benefits of investigating further based on the dangers of doing so, the risk factors the patient has, maybe even what you see in successive scans over time?
I am not a doctor, but there seems something unhealthy about a system in which you are advised to avoid learning information about yourself in order to avoid treatment.
One dilemma I've been thinking about recently is that there's an unfortunate burden put on care providers due to litigation that results in increased cost - the provider or radiologist that sees a "maybe" or a "shadow" on an image has to order a biopsy just to protect themselves from being sued on the off 1% chance that the thing becomes a serious health concern. In an environment where consumers evaluated their medicine based on value/$ they would be further dissuaded from a biopsy, but in America the nature of medical insurance disincentives this sort of cost analysis skepticism.
It's hard to resolve becuse it's not even about money. It may be the doctor who is blaming himself.
So it's not that they can't act with sense and restraint with respect to risk. They clearly can.
With respect to breast cancer specifically, they told me in school that finding it early improved your odds, and the earlier the better, and if you really wanted to do the right thing, you'd physically examine yourself looking for lumps on a monthly basis. That didn't seem unreasonable - and yet when something more accurate and objective is available, it's to be avoided out of a fear of unnecessary biopsies?
Something strange is going on.
That's not the current advice. Current advice is that women become aware of what's normal for their breasts, and look for certain specific changes and not the vaguely described "lumps".
http://www.nhs.uk/chq/pages/1740.aspx?CategoryID=60&SubCateg...
> and yet when something more accurate and objective is available
Is it more accurate? Mammograms are sensitive, but have a high false positive rate, especially for younger women.
(All the sites I can find report sensitivity and false positive rates as percentages, which is a terrible way to report this information.)
https://ww5.komen.org/BreastCancer/AccuracyofMammograms.html
> Overall, the sensitivity of mammography is about 84 percent [9]. This means mammography correctly identifies about 84 percent of women who truly have breast cancer.
> The more mammograms a woman has, the more likely she will have a false positive result that will require follow-up tests. The chance of having a false positive result after 10 yearly mammograms is about 50-60 percent [22-24].
http://www.breastcancer.org/symptoms/understand_bc/statistic...
> In 2017, an estimated 255,180 new cases of invasive breast cancer are expected to be diagnosed in women in the U.S., along with 63,410 new cases of non-invasive (in situ) breast cancer.
Ann, a 45 year old woman, goes for a mammogram. It returns a positive result. What are the chances that Ann has breast cancer? (Scarily lots of doctors can't answer this question if the information is presented as percentages. See Gerd Gigerenzer's book Reckoning with risk for many examples.)
https://www.cancer.gov/types/breast/hp/breast-screening-pdq
> Magnitude of Effect: In the randomized controlled trials (RCTs), for women aged 40 to 74 years, screening with mammography has been associated with a 15% to 20% relative reduction in mortality from breast cancer.[1] Absolute mortality benefit for women screened annually for 10 years is approximately 1% overall, ranging from 4 per 10,000 women who start screening at age 40 years to 50 per 10,000 women who start at age 50 years.[2] Based on the 25-year follow-up from the Canadian National Breast Screening Study (CNBSS), an RCT of breast cancer screening,[3] there is some uncertainty about the magnitude of benefit of mammography in the present day.
The problem is this: How do you when to investigate further and when not to? Unless you can come up with a way to make that choice without just rolling dice, you're not really doing any better.
> ... the risk factors the patient has, maybe even what you see in successive scans over time?
Aside from perverse incentives as mentioned by someone else, there may also be a risk from the scan itself (as in breast cancer screening, e.g.). There's also secondary effects from a positive scan like anxiety before being able to confirm or reject a diagnosis -- this has known health effects. The confirmation itself may have associated risks, etc.
It's far from clear that the benefits outweigh the risks[1], so it seems like overkill to call this an indictment of medicine.
(I should also add that in e.g. breast cancer women who are known to be at risk -- there's specific genes which carry very high risk (BRCA1, BRCA2) and other genetic factors with high penetrance.)
[1] This is also something that many in the medical profession acknowledge, see for example [2] where there's a load of material on breast cancer, specifically.
We do a lot of research scans on healthy volunteers. You scan certain areas with some trepidation. Scanning the liver of a 50 year old is a great way to find yourself in a world of 'incidental finding' paperwork.
I'm imagining new technology here.
You'd take the first scan as a baseline. Whatever lumps you have are assumed harmless. Then you track the diffs from there on.
I assume that, at least after collecting experience, we can learn to tell the bad growths from the ignorable.
It seems only logical that occasionally there would be something detected which is unambiguously cancer. The ones that are ambiguous, we could simply monitor without taking action on.
If having more information about the state of your health is putting you in danger, then the medical system is broken. It's as simple as that.
It's not exactly $20, but I'd hardly call it prohibitive.