[HN Gopher] Philips recalls 340 MRI machines because they may ex... ___________________________________________________________________ Philips recalls 340 MRI machines because they may explode in an emergency Author : LinuxBender Score : 66 points Date : 2023-12-24 19:24 UTC (3 hours ago) (HTM) web link (www.theregister.com) (TXT) w3m dump (www.theregister.com) | BobaFloutist wrote: | Well that's definitely not what they're supposed to do. | jt2190 wrote: | The Food and Drug Administration's web page about the recall is | clearly written: | | (edit: actually not a recall but a requirement that the machines | are not used until they're serviced) | | https://www.fda.gov/medical-devices/medical-device-recalls/p... | akira2501 wrote: | That's absolutely a recall. An FDA recall means the product is | in violation of the law. Those violations must be corrected or | the device must be destroyed, and if not, then the FDA has the | right to seize it. | | The recall strategy in this case is not to ship it back to the | manufacturer, but to have the manufacturer come out and service | the device until it is again compliant with the law. | s1artibartfast wrote: | It has very little to do with the violations of the law. | There is no law that states mri machines must have <X% chance | of exploding. | | The way these things work is that the firm has decided based | on their data and reports to issue a recall and notify the | FDA. The manufacturer recommends hospitals not use the | device, however there is the possibility that they continue | to do so (the probably won't for liability reasons). | pkaye wrote: | Take the number of MRI machine in the field, A, multiply by | the probable rate of failure, B, multiply by the average | out-of-court settlement, C. A times B times C equals X. If | X is less than the cost of a recall, they don't do one. | Jabbles wrote: | _There has been one reported event of an explosion in 22 years | of use. There have been no reports of injury or death._ | | I wonder what the total negative health consequences of not | being able to use all those MRI machines until they are | serviced will be. | fnordpiglet wrote: | Also doesn't say it happened to a Phillips machine, my read | is that's for any MRI machine - ever. | | So, yeah, a recall, but nothing ominous about it. Things get | recalled all the time. | sverhagen wrote: | Yet the press this is getting is, like the article said, a | black mark on Philips. They were a very diverse company, | until they chose a few specific markets in which not to | divest, healthcare being one of them. This must be quite | the chill at headquarters. | pstuart wrote: | It's a pity that the helium is vented out, considering its | increasing rarity. | | I'm guessing that capture and reuse probably would add way too | much to the price of the machine. | Metacelsus wrote: | It can be recovered, see for example: | https://news.ucsc.edu/2019/12/helium-recovery.html | fabian2k wrote: | This is about quenching, which happens in emergencies or | failure. During regular use helium is recycled in similar | systems often today. But it's simply not feasible to do that | when all the liquid helium in there evaporates at once | cperciva wrote: | If you suddenly have thousands of L of He gas on your hands, | venting is better than exploding. | namibj wrote: | The issue in that respect is that they flood the coils in a | helium bath, instead of utilizing additional structures like | channels/nozzles to provide the same rate of freshly cooled | helium to the heat sources as the bath does, but with far less | helium required in the system. | fabian2k wrote: | I don't think any similar magnet exists that doesn't embed | the magnet in a dewar full of liquid helium. And it probably | doesn't make any sense to do it differently, even if it were | possible. | | You need some mass here for the helium anyway as you never | ever must run dry and it constantly evaporates. | ars wrote: | This only happens in an emergency, not during normal operation. | | Pretty much the only time you would do it when a person is | stuck in the machine by some piece of metal that is attracted | to the magnet. You hit the quench button which vents all the | helium, but more importantly also halts the magnet (all the | energy released from halting the magnet goes into boiling the | helium), and then you can release the person. | | You don't do this for any other purpose, for example if some | metal cart is stuck in the machine, but no one is at risk, you | use a slower method to shut down the magnet (i.e. drain the | energy) that doesn't vent the Helium. | londons_explore wrote: | I was under the impression that metal 'sticks' to an MRI | machine with so much force it will usually puncture the | machine and all the helium will leak out .. | fabian2k wrote: | Large metal objects can cause a quench. Smaller and medium- | sized ones usually won't, they will just stick to the | magnet until you release them. | akira2501 wrote: | Liquid helium has a 745:1 expansion ratio when converting into a | gas. So, that's not a fun problem to have. | lnxg33k1 wrote: | Its unbelievable the decline of philips, i used to buy their | stuff out of trust, but given their story with ventilators, this | one, and other personal ones with razors, waterfloss and | toothbrushes, I wouldn't touch anything from them with a ten foot | pole | terom wrote: | > There has been one reported event of an explosion in 22 years | of use. There have been no reports of injury or death. | lnxg33k1 wrote: | So they don't explode when they're new, but after a while? | How old was the machine exploding? | | Not sure how your message disproves mine, this would be the | second recall in few years for philips, whatever, doesn't | come through as high quality | krisoft wrote: | > So they don't explode when they're new, but after a | while? How old was the machine exploding? | | No. What they say that the problem occurs only very rarely. | The first of this MRI model was introduced in 2001, there | are hundreds of them used all the time and only one | explosion happened. Presumably that is the explosion which | has shown them that there is something wrong with the | model, and now they are taking corrective action. | | > this would be the second recall in few years for philips | | It is a huge company doing a lot of things. The safest way | to never make a mistake is by sitting on your hand and | refusing to do anything. | | Some of the affected MRIs are old enough now to buy you a | alcohol, how is this an evidence of anything recent with | Philips? | | > whatever, doesn't come through as high quality | | They found a rare but potentially high impact issue and are | fixing it in decades old equipment on their own dime. | | Show us that you have done things of similar complexity | better. What equipment you have designed is in constant | operation since 22 years? How do you know it doesn't have | any low probability, high consequence failure modes? | CharlesW wrote: | The parent commenter isn't just talking about this recall, | but what appears to be a developing pattern: | https://www.nytimes.com/2023/09/07/health/cpap-defect- | recall... (https://archive.is/gvqmN) | | > _The lawsuits have claimed that flaking foam and gasses | emitted from the machines were linked to health issues | including respiratory illnesses, lung cancer and death. The | foam was used in the machines to reduce noise and vibration._ | | > _In June 2021, the Food and Drug Administration announced a | recall of Philips machines that also included BiPAP devices | and ventilators made since 2009, warning that foam | deterioration in the products could cause "serious injury" to | users. Philips initially released a memo to doctors saying | the foam breakdown posed risks of "toxic carcinogenic | effects," but the company has since released updates | reporting a far lower level of concern._ | hinkley wrote: | "I don't wanna explode." | trebligdivad wrote: | I dont understand what the fault is - quenching is bad but | happens. Blocking the quench path sounds bad - is it saying that | something is causing it to be blocked or is the machine supposed | to do something else if hte quench path is blocked (what can it | do??) | EA-3167 wrote: | The rapid conversion from liquid or solid to gas, and the means | to (briefly) contain that... is a _bomb_. The reason you don 't | block the emergency relief is that you turn a quench from an | emergency involving asphyxiation, to something resembling a | detonation. | trebligdivad wrote: | Right, but that's true of all MRI's - so what's different in | this one? | refulgentis wrote: | "During a quench, which is not common, a large amount of | helium evaporates and is vented outside the building | through a venting system," the recall explains. "If an | unknown blockage is present in the venting system and the | pressure exceeds design limits, the structural integrity of | the system could be compromised." | op00to wrote: | This is a risk of any mri machine that uses helium to | cool a magnet. Why are only these machines being recalled | when if you block the exhaust of any mri scanner it will | blow up? | jabiko wrote: | This is just speculation, but maybe there is a secondary | rupture disk that vents the helium inside the room when | the primary path (the exhaust to the outside) is blocked. | And maybe that secondary rupture disk is too strong, so | another random part of the helium containment fails, | blowing up the machine and possibly injuring the patient. | But please note again that this is pure speculation. | s1artibartfast wrote: | That doesn't explain what is different. I assume that is | a feature common to all machines. | Piezoid wrote: | Why not add a pressure relief valve on the quench path | with a very loud whistle? That should be enough to take | care of such rare and compounded failures. | | What does recall means in this context? De-energizing the | superconductor and shipping it back? Seems like a waste | and a planning nightmare. | userbinator wrote: | I suspect this recall is precisely because someone | figured that the relief path wouldn't work. | crest wrote: | The Helium used for cooling expands a lot going from liquid to | gas during a quench (iirc by a factor of ~1800). The pressure | built-up from the phase change has to be relieved *quickly* | before the machine turns into a crude pipe bomb. Oh and you | can't get enough Oxygen from the air if most of it has been | replaced with leaked Helium. | jokoon wrote: | I worked in x ray imaging software in a company that assembled | them. | | Risk assessment and traceability are not fun, but it's | interesting to see how to make safe things. | | I wish general software had similar constraints or designs, or at | least insurance companies would lobby the government to force | software companies to proof read their code. | | I don't want rust everywhere, but it should still be possible too | approach what rust is doing by other means. | serial_dev wrote: | Toxic teams and lazy developers will also find way to produce | crappy software with Rust. | | The Rust developers of today might produce better software, | because they are the early adopters who care about performance, | safety and correctness, but I believe (assuming Rust becomes | mainstream) if you give regular developers Rust to code in, | they will produce the same quality as they do with Java, | Javascript, or C. | | The environment and the individuals are significantly more | important than the programming language they use. | refulgentis wrote: | Where would i go to learn the fine details of how things like | risk assessment and traceability work in practice? | cperciva wrote: | Note: MRIs are incredibly safe. Your risk of dying due to an MRI | machine exploding is significantly less than your risk of dying | due to falling while climbing into the machine. | fabian2k wrote: | You should respect the magnet though. Those warnings aren't | there without reason, getting between an MRI or NMR and a | magnetic piece of metal is a bad idea | cperciva wrote: | Oh, absolutely. MRI machines are incredibly dangerous if not | handled properly. But the overwhelming majority of MRI- | related dangers are well understood and avoidable. | pengaru wrote: | Case in point: https://www.miamiherald.com/news/nation- | world/national/artic... | figmert wrote: | ~~I don't know why this is relevant, and quite frankly I find | comment odd. Just because y is safer than z, does not mean we | should ignore reasons why z isn't safe.~~ | | See OP's response for why this is crossed out (assuming HN | supports it). | cperciva wrote: | I think it's an important point to reinforce because news | stories like this can make patients afraid of MRIs, | potentially resulting in them avoiding necessary imaging. | Most people on HN are probably not going to make that error | -- but I think we have a responsibility to help communicate | to the broader community in this regard. | serial_dev wrote: | Each man is the architect of his own destiny. | | If someone is afraid of MRI machines exploding (I've never | met anyone like that), they will need to live with the | consequences of that decision. | s1artibartfast wrote: | Of course. But that doesn't mean it isn't worthwhile to | be clear on what the factual risks are. | figmert wrote: | Great point, and it makes sense. Thanks for clarifying. | dukeofdoom wrote: | At what point are less safe but cheaper machines worth it. | Hospitals ration MRI machine access through out the world. Even | in Canada, you have to wait on a list to get access. | | "Canada could expect to wait a median of 5.4 weeks for a CT scan | and 10.6 weeks for an MRI scan" | lnsru wrote: | Is it not the case, that wait time goes to zero if you pay in | cash immediately? | mattlondon wrote: | FWIW in the UK I was able to get a MRI the next day when | going private. They even gave me a CD with the images. | | They would have even done it the same day but _I_ wasn 't | available. | | I suspect in the NHS I wouldn't have even got a MRI at all | (it was for a mildish running injury to my knee and just | needed some physio in the end, so MRI seemed like overkill!) | LegitShady wrote: | thats because Canada has less than 20% the MRI machines | proportionally to population as Japan, and 25% of the MRI | machines as the US. We're down near the Czech Republic and | Turkey. | | From 2019: | | https://www.statista.com/statistics/282401/density-of-magnet... | | I didn't look very long so maybe there's more recent numbers | available. ___________________________________________________________________ (page generated 2023-12-24 23:00 UTC)