It’s wild that the bottleneck keeping us from buying more MRI machines, achieving economies of scale for a no-radiation way of viewing soft tissues in high resolution, is supposedly the specialized technicians, and here we had a technician who couldn’t manage to turn it off in time when something went wrong, and apparently didn’t keep metal objects out of the room. (We use metal detectors any time you walk into a sporting event, why not an MRI room?)
I expect this story to be promoted by people who benefit from sales of x-ray / CT machines though. MRIs and all of their promise for public health could continue to be set back.
You can't turn it off, it's a static magnet with hundreds of amps flowing in a closed loop in a giant superconducting coil. The usual comparison is that a charged magnet has the same kinetic energy as a loaded 747 coming in to land. To "turn it off" you can bring it above superconducting temp, dissipate all that power as heat, and boil off thousands of liters of helium (fun fact, they usually have ducts to outside for this so everyone doesn't suffocate during a quench). Which might have happened in this case due to physical damage to the magnet, but is not as easy as flicking a switch and having it be "off".
> The usual comparison is that a charged magnet has the same kinetic energy as a loaded 747 coming in to land.
That sounds like it a bit of an overstatement. 200 tonnes of 747 at 250kph is nearly 500 MJ. Even the biggest, baddest high-tesla MRIs are maybe 10MJ. Which is still a 67-tonne M1 Abrams at 40 mph, so it's not like it's an unimpressive amount of energy!
Sure, a tank can stop from 40mph in not much time due to a very big braking system (https://youtu.be/f5XUQ2beGfM?t=85), but also a tank at 40mph will utterly demolish an MRI suite, patient and all if it drives into it.
A magnet yanking a chain around your neck isn't going to slowly suffocate you either. It's going to instantly crush your trachea and maybe your spinal chord, like a drop from a hanging.
The facts as reported in the article indicate that he was able to say goodbye before being suffocated. I wouldn't call that "instantly crush your trachea and maybe your spinal chord".
Okay, this sounds more serious than I thought. But then, why was someone able to walk into that room with metal around their neck if it was clearly so life-threatening?
Anyway, I’m complaining as someone who personally has turned down recommended medical procedures after checking radiation cancer risk numbers and realizing the radiation risk was being downplayed. When I saw the numbers, to me the cancer risk wasn’t worth it, so I went without a solution to my health problem. Had an MRI been an option, I would have more likely said yes.
> But then, why was someone able to walk into that room with metal around their neck if it was clearly so life-threatening?
Take a look at the Google Street View link someone posted. It's pretty clear this facility -shouldn't- have been able to acquire an MRI machine in the first place.
It also elucidates how such an accident could happen, i.e they clearly don't have the trained staff and protocols necessary given the danger of an MRI machine.
It's very likely the poor gentleman didn't understand the immense danger the machine poses.
They are expensive and rare for a reason IMO. Yes it would be great to have more of them but the best place for more of them is within proper hospitals and leveraging economies of scale to share technicians across a fleet of them in a well run facility.
You got the MRI magnet dissipation-time completely wrong, but it hasn't influenced your opinion on the radiation risk in other similarly sophisticated equipment that could save your life?
A hasty incorrect assumption that I revised on new information is obviously not the same as hard data on radiation doses and cancer implications considered over weeks.
The “could save my life” odds were not very clear and the risk of cancer for that radiation dose had been long ago quantified by scientists, though without considering the immunosuppressants I was taking at the time that elevate cancer risks, making those rates more of a best-case scenario than something to count on. Above all else, the number known to the healthcare facility was the dollar amount to bill to my insurance, with the facility receiving nothing but money in exchange for taking those risks with patients’ lives.
For reference, in exchange for 10 mSv of radiation, a moderate dosage for a CT scan, the cancer risk for a young adult is something like 1/1000 over the course of their life. This means that out of every 1000 young adults who receive a 10 mSv CT scan, 1 would go on to get cancer they otherwise would not have gotten, assuming those 1000 aren’t already at higher risk of dying sooner (this assumption is important to weigh but is not straightforward). Those odds sound low, but if there was a revolver with 1000 chambers and one bullet, would you play Russian roulette with that if your life wasn’t on the line? The risk of cancer for the same radiation dose is much higher for children.
A technically clear answer to this is to use MRIs wherever practical, and to make MRIs more practical as much as we can. Why accept 10 mSv of radiation when you could just do an MRI instead? We should be making MRIs more and more practical. I’m concerned about the potential fear-mongering over times like this one when the facility fails to perform an MRI safely, where the impression people get could be that MRIs are dangerous, when the hazard was really the facility doing a bad job. By contrast, a perfectly performed CT scan will deliver a known radiation dose to the patient every time.
> The usual comparison is that a charged magnet has the same kinetic energy as a loaded 747 coming in to land
So once you divide by the "lying to people allegedly for their own good and trading away credibility in the process" factor what does that come out to? A semi truck at highway speeds? Those can stop in under 10sec.
It isn't a binary like that with the MRI though. If it stops strangling you in 10sec you're great, 15 you're fine, 20 you need to be woken back up.
Edit: Per the article that you have all supposedly read, he wasn't instantly incapacitated. He was pinned onto/into the machine with enough weight on him that he suffocated over seconds and ultimately died at the hospital. This would have been a "close call" with an E-stop (which they likely had, just wasn't hit soon enough).
I don't know, I imagine getting suddenly jerked across the room by your neck is not a slow and gentle strangulation event. In addition, as I understand it, currents can be induced in metal objects causing them to heat up. So no, I'm not sure that 15 seconds of violent burning strangulation of an elderly individual is fine. It's not clear this fellow died from strangulation.
I expect this story to be promoted by people who benefit from sales of x-ray / CT machines though. MRIs and all of their promise for public health could continue to be set back.