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How do MRI Headphones work? (2022)
- riffic 2y agotldr it's a pneumatic tube like a stethoscope. these used to be used within aircraft as well for inflight entertainment.
- lxgr 2y agoI've been on an airplane that used these! I think it even had a channel selector near the plug if I remember correctly (it's been a while).
- riffic 2y agoEDIT i'm wrong the speaker was inside the armrest. I wouldn't be surprised if the channel selector wheel was a simple mechanical acoustic coupler rotating to connect or cap upstream source tubes. I remember it as well flying in the late 80s or early 90s.
- denton-scratch 2y ago> a simple mechanical acoustic coupler I get what you're saying, and I think that's plausible. But as far as I'm concerned, an acoustic coupler is/was a type of modem, into which you plugged an ordinary telephone handset. You had to have a telephone that had hemispherical mike and earphone; it didn't work with e.g. a trimphone. Expected performance: 9,600 bits-per-second.
- riffic 2y ago"coupling" then, whatevs. lemme see if I can dig up a patent number for the channel switcher wheel and put this pondering to rest. seems the inventing corporation is still around haha https://avidproducts.com/2023/12/08/celebrating-70-years-of-avid/ https://avidproducts.com/2023/12/08/celebrating-70-years-of-...
- throwway120385 2y agoYep right next to the ashtray.
- ortusdux 2y agoI remember being able to select the pilot coms. I was nervous on my first flight as a kid, and it was very calming to hear the preflight checklist and ATC communication in the classic pilot cadence. This was pre 9-11. I did wonder on my last flight if I could use SDR & android to listen in.
- lxgr 2y agoYou can just use LiveATC on your phone these days, since many flights now have gate-to-gate Wi-Fi. I think it's not allowed to actually operate a radio receiver on an airplane in the us: https://travel.stackexchange.com/questions/2322/can-i-listen-to-air-traffic-control-on-a-flight https://travel.stackexchange.com/questions/2322/can-i-listen... Some airlines might still have the "listen to ATC" feature available, but in my experience, it's the pilots' decision whether that's available or not, and I've only ever been able to use it on a United flight once. Sirius XM on JetBlue also has an "ATC channel", but I've only ever heard silence there, and I'm not sure if that's a similar thing (i.e. sourced locally), or just a random ATC feed from somewhere in the country relayed via satellite.
- deleted 2y ago[deleted]
- doctorhandshake 2y agoI used to love trying to surreptitiously unplug my traveling companions’ headphones so I could blow into the end of the tube. Never once pulled it off.
- myfonj 2y ago> The sound is transported along the tube via air — a very simple solution. Though this also explains why they sound absolutely terrible. I see it is simple, but I wonder, would it be possible to use different sound medium ("conductor")? Some liquid, water perhaps? Would elasticity of the tube eat more signal than is lost in the air? Too heavy? Leaky? Questions…
- focusedone 2y agoThis guy also has a post about the hierarchy of socks and underwear which resonated with me. https://tomlingham.com/articles/an-unfortunate-hierarchy-of-socks-and-underwear/ https://tomlingham.com/articles/an-unfortunate-hierarchy-of-...
- thisgoesnowhere 2y agoInteresting how different people's minds are. I find the exact opposite problem, I go with old faithful over new. It's for this reason that when I put my clothes away I simply take the stack of clothes in my dresser out, put all the fresh stuff on the bottom, then put the clothes that were in the drawer stuff on top. I always grab the top sweater, t-shirt socks etc and I don't think about it at all.
- adolph 2y agoFILO is not the standard method of maintaining one's stock of clothes? How else does a person mange wear leveling?
- edward28 2y agoSimply pop from the bottom of the dresser.
- adolph 2y agoThat method seems like it would have more cumulative effort than loading the cleaned clothes under the stack once a week. Additionally, I would probably rumple the stack pulling something out from underneath.
- thfuran 2y agoI use a queue of stacks for each regularly used item type. Laundry is enqueued on one end of the drawer and popped from the other, with stacks slid over as needed.
- djhope99 2y agoI thought these were a nice idea when I had my MRI the other day, little did I know that I would barely be able to hear anything over the noise of the MRI machine. Ear plugs were better, kept out the noise of the MRI machine and let me drift into a trance.
- dylan604 2y agoWhat was your experience with the MRI like? Specifically, did you "feel" it? I've had my knee scanned for ACL damage, and have spoken to a few other acquaintances that have had scans as well. We've all discussed having some sensation in the exact part of the body being scanned. We all just happened to similar sports based knee injuries. It was just the slightest of tingling, but noticeable. Definitely not painful or anything scary. Was it just psychosomatic? Very possibly, but it's interesting that we all experienced it.
- tgv 2y agoMRI can cause a tingling sensation. Apparently, it can be quite noticeable when you make a loop, e.g. with your arms. See peripheral nerve stimulation.
- dylan604 2y agomake a loop? wouldn't that require breaking the cardinal rule of not moving during the scan?
- green-salt 2y agoFor my knee scans I could move into a position that was comfortable for me which actually I think was arms folded across my abdomen, but then you just do not move while the imaging is happening, which will have a distinct sound.
- zrail 2y agoI have had an abdomen MRI. I definitely felt sensations when the machine was doing particular sets of scans. Also, I accidentally left my wedding ring on (I informed them, they were not interested in the slightest). My right felt hot during the scans. Not painful burning hot, but warmer than body temp for sure.
- cuonic 2y agoThey also use a similar mechanism for the "get me out of here ASAP" panic button [0] that staff place in your hand and tell you to squeeze if required, all it does is detect a change in air pressure on the other end of the tubing. [0] https://www.mriequip.com/store/pc/MRI-Non-Magnetic-Magnalarm-Patient-Panic-Alarm-p295.htm https://www.mriequip.com/store/pc/MRI-Non-Magnetic-Magnalarm...
- DennisP 2y agoMy house came with a button like that for the garbage disposal. Previous owner didn't like the idea of using an electrical switch with wet hands.
- Aachen 2y agoA button for garbage disposal before you have a chance to dry your hands? What does this button do, activate some pneumatic tube system so you don't have to carry trash to the bin?
- PufPufPuf 2y agoThey're talking about the "trash blender" that's common to be installed in American sinks
- Tagbert 2y ago“Trash compactor” It is an in-cabinet trash can with a mechanism to compress the trash when you push the button. I don’t know how common they really are. I’ve only know a few people with them. I could see where they might be more popular in apartments where you can’t easily take your trash to an outside trash can. They do require special, heavy-duty trash bags to handle the pressure.
- DennisP 2y agoWhat I'm talking about is an electric grinder that that sink drains into. Lots of people have them in the US.
- FriedPickles 2y agoI was intrigued to see a lady at the crosswalk the other day wearing earbuds with thick tubing instead of wires. Googling it, I discovered they were "EMF free headphones". Apparently enough people think electromagnetic radiation in the ears is a problem that there are now dozens of these headphones on the market that put the driver half way along the cord, with tubes proceeding to the earpiece.
- edward28 2y agoIt would be a real shame if EMF could propagate.
- 77pt77 2y agoAs long as it's slowly maybe you can catch it. It it was at the speed of light we might have a problem.
- gumby 2y agoTo be fair, EMF is 1/r^2 so the transducers (speakers) are indeed far from the ear. Not that they need to be, but...
- jollyllama 2y agoThey're also more durable; i.e. resistant to running over the tube portion with a chair.
- Aurornis 2y ago> Apparently enough people think electromagnetic radiation in the ears is a problem Even Andrew Huberman, one of the most popular health science podcasters, has dabbled into anti-EMF quackery. On one podcast he claimed that his Bluetooth headphones produced notable "heat effects", implying that the electromagnetic energy was enough to produce palpable heat in his body. It's obviously placebo effect to the extreme (physically impossible given the amount of RF energy) but nevertheless he made the claim. Millions of people listen to that podcast. Of course, people are catching on that Andrew Huberman isn't really a good source of scientific information (nor really a good person, given recent revelations) but the damage is done.
- snakeyjake 2y ago>The only headphone tech that I was aware of or that I'd ever really considered I guess I'm old now because this style of headphone was present on every model of passenger aircraft in the sky when I was a young adult.
- mlfreeman 2y agoI remember putting my ear up to the little holes and faintly hearing the audio even without anything plugged in.
- treve 2y agoI've never heard this before! When I started flying it was just the 2 mono jacks that you still see on planes that haven't been updated (always wondered why it wasn't just a stereo jack) Pretty surprising to hear there's air/sound tubes rigged on to every seat on a plane. Seems like the sound tubes ended in the 70's: https://apex.aero/articles/sound-tube-surprising-history-airline-headsets/ https://apex.aero/articles/sound-tube-surprising-history-air...
- riffic 2y agothe inventing company is still around https://avidproducts.com/2023/12/08/celebrating-70-years-of-avid/ https://avidproducts.com/2023/12/08/celebrating-70-years-of-... apparently the speaker was in the armrest.
- ben1040 2y agoI flew some overseas trips on Delta 767s in the late 1990s that still had the tube headphones. I was pretty intrigued by the concept, you could hold your hand up to the tube holes in the arm rest and hear the music echo off your hand. Either on the headphones themselves or in the little overwrap bag there was a note to leave them on the aircraft when you deplane, because they (obviously) wouldn’t work elsewhere.
- helpfulContrib 2y ago[dead]
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- lynx23 2y agoAhh, memories. Roughly 20 years ago, I took part in a research experiment which had as its aim to figure out which brain areas were involved when a blind person reads Braille. TL;DR: They had a hypothesis, which was mostly confirmed. It happens in the visual cortex. Anyways, back then, MRI was still newish tech. FMRI wasnt used much in typical medical settings, but for research. As part of the deal, the MRI technicians did share a lot of gossip and random knowledge during the rather long preparation times. Long story short, this is when I learnt about the tubed earphones. And all the other mechanisms which were constructed to transport the braille strip wthout operating a real motor inside the magnetic field... Was almost worth the 4 hours of having to absolutely lie still...
- koliber 2y agoCompletely tangential story. A few months back I was getting an MRI. I stashed my belt, coins, keys, and phone. The machine started its clicking and thumping when I realized I had my wedding band on my ring finger. Immediately my mind raced to a video I once saw of an MRI machine propelling a fire extinguisher across the room. I braced for my finger to be torn off while I slowly took the wedding band off using only one hand. Luckily it stayed put through the whole scan and nothing happened.
- randlet 2y agoIf it was ferromagnetic you would likely feel it tugging as you got close to the magnet. Gold, silver, titanium are ok in MRI. However, next time, the second you realize you have metal on your person you should immediately inform the techs rather than try to just hold onto it! Aside from the risk of injury, it can be a real pain to get stuck items off the machine.
- lostlogin 2y agoTaking off metal jewellery in the scanner is about the worst thing one can do - it’s then loose. It would be very unlikely to move from a clenched fist, even if ferromagnetic. However having it escape your hand isn’t that difficult. I’ve seen most these things play out. And as you say, it’s exactly what the call bell is for.
- dessimus 2y agoI forgot to take my tungsten carbide wedding band off as well for an MRI, nor did the MRI techs say anything. It was in the middle of the MRI scan that I realized it was still on and then my fingers on the ring hand kind of started to feel fairly warm, but not certain it that was actually the ring picking up magnetic energy or if it was psychosomatic, but no harm became of it. I looked it up afterwards and tungsten apparently as little to no magnetic effects, but depending on the amount of carbon used in it, it can.
- lostlogin 2y ago> little to no magnetic effects Whether or not it’s a conductor is probably more of a concern. The loop likely wouldn’t be large enough to cause any drama though.
- denton-scratch 2y agoI haven't flown for many years; but I think I remember airline headphones that were connected to the seat-handle with a hollow plastic tube. They were awful.
- amelius 2y agoSo they work like a stethoscope. Would they sound better if they used a liquid instead of air for the conduction?
- timvdalen 2y agoI made the mistake of brining an episode of 99% Invisible to an MRI. The sound quality is so bad that you barely can't make out voices. It was excruciating to listen to something I could almost understand for that time.
- EnzymeFestival 2y agoWhat options exist for something superior? These headphones are awful
- astrodust 2y agoStimulating the audio processing part of your brain directly with the MRI machine.
- ricardobeat 2y agoElectrostatic headphones: https://www.audeze.com/blogs/audeze-journal/press-release-for-the-audeze-and-smrt-image-collaboration-for-crbn-electrostatic-mri-headphones https://www.audeze.com/blogs/audeze-journal/press-release-fo...
- Retr0id 2y agoMEMS https://usound.com/usound-introduces-patient-safe-mems-loudspeaker-for-mri-compatible-headphones/ https://usound.com/usound-introduces-patient-safe-mems-louds... Datasheet (PDF) https://usound.com/download/achelous-datasheet/?wpdmdl=746 https://usound.com/download/achelous-datasheet/?wpdmdl=746
- roywiggins 2y agoYou can technically alter the sequence to make the scanner itself produce music. I don't know if anyone actually does this... https://pubmed.ncbi.nlm.nih.gov/26178439/ https://pubmed.ncbi.nlm.nih.gov/26178439/
- lakpan 2y agoHire a non-metal band to play for you in the room.
- DavidVoid 2y agoHigh-end headphone brand Audeze recently made an electrostatic headphone that works in MRI machines.[1] No air tubes needed and much better sound quality (and much more expensive). [1]: https://www.audeze.com/blogs/audeze-journal/press-release-for-the-audeze-and-smrt-image-collaboration-for-crbn-electrostatic-mri-headphones https://www.audeze.com/blogs/audeze-journal/press-release-fo...
- m463 2y ago> [Audeze has since made an audiophile version, called the CRBN headphone, read that story here.] Very vague explanation of how they work, and that link in the middle - I suspect that is the entire point of the press release.
- lmz 2y agoWell it says the headphones are sold by the MRI company: > The CRBN headphones are integrated into the Lumica AV system from SMRTImage that provides images and movies Maybe you can get more info out of them: https://www.smrtimage.com/ https://www.smrtimage.com/
- anfractuosity 2y agoInteresting, sound kind of like a stethoscope. I bought a kind of unusual type of headphone from aliexpress a little while ago, that essentially consists of an induction loop you wear round your neck and tiny magnets you put in your ear, I'm somewhat scared to try them out as I don't especially want them to get stuck in my ear.
- birdman3131 2y agoI must be from a different era because a cup and string was well known as a kid as a way of transmitting sound. This is a very similar process.
- fluidcruft 2y agoOne of my favorite ISMRM posters that I saw in Toronto years ago was titled something like "a low-cost MRI-compatible communication system". It was really well written and you had to look at the photos to fully realize it was actually two Dixie cups connected by a string.
- throwaway2037 2y agoMan, you really nerd sniped me here. First: ISMRM means "International Society for Magnetic Resonance in Medicine" from here: https://www.ismrm.org/ https://www.ismrm.org/ I found a bunch of posters here, but I could not find the exact one that you mentioned: https://www.ismrm.org/19/program_files/DP02.htm https://www.ismrm.org/19/program_files/DP02.htm Maybe lost now? Or a different page?
- fluidcruft 2y agoI'm pretty sure it was the 2008 ISMRM meeting (small chance it may have been 2003). I don't think it was actually submitted, because I couldn't find it in the proceedings even back then. I think whoever it was smuggled the poster into the hall and hung it among the others as a prank. I'm pretty sure the dead salmon fMRI poster was also there at the time but I can't remember if that was in the proceedings. The dead salmon fMRI did end up being published though and making quite a stir.
- jagged-chisel 2y ago> I'm not allowed to have any metals or magnetic materials on me. Loose or easily dislodged materials. My belt buckle was ok to keep on. Had to empty my pockets, take off my ring, metal piercings are disallowed. You don’t want gobs of belongings piling up on your magnet, and you don’t want something large enough to pin the human between it and the magnet. The first scenario is quite expensive to rectify. The second is quite expensive, quite painful, probably fatal, and certainly traumatic.
- roywiggins 2y agoAlso important: no fabrics with metal fibers. https://www.ajnr.org/content/34/5/E47.full https://www.ajnr.org/content/34/5/E47.full
- bpye 2y agoDoes this possibly depend on the field strength? I was asked to change into a hospital gown when I had an MRI a couple years ago.
- lostlogin 2y agoThis is standard practice at many places and should be standard everywhere. The American College of Radiology say the below [1]. ‘it is advisable to require that the patients or research subjects wear site-supplied MR Safe scrubs or gowns in place of their own clothing and undergarments in the region undergoing direct RF irradiation.’ Slightly odd - this appears to be about burns rather than projectile risk. Anecdotally, sites that don’t change patients have more accidents. [1] https://www.acr.org/-/media/ACR/Files/Radiology-Safety/MR-Safety/Manual-on-MR-Safety.pdf https://www.acr.org/-/media/ACR/Files/Radiology-Safety/MR-Sa...
- fortran77 2y agoThis is exactly how headphones on passenger airlines worked several decades ago, until about 1990.
- aitchnyu 2y agoTangential, I saw an episode of House where he put a patient with medical implants into an MRI and they ran it for a few seconds till the burning was too painful. Was this realistic?
- lostlogin 2y agoIt happens sometimes. I’ve been there for it with an infected filling (patient was unaware - they went to a dentist and reported back), with tattooed eyebrows and anyone with a cochlear implant tends to suffer (from the torque, not heating). There is the odd burn - rare, and mostly preventable. Burns are the most common class or MRI injury. I’m an MR tech.
- tsol 2y agoI remember there was an episode where this happens with a prison tattoo-- some of them can contain heavy metals that react in an MRI.
- Traubenfuchs 2y agoOk, interesting, makes sense. Next, explain to me why the MRI machine does not... take itself apart? In an MRI machine without a cover you can see all kinds of micro and macro machinery, cables, fans, plating, sensors, magnetrons, pulse transformators, gun drivers... Pretty much each of those parts would be pulled through the room and get stuck to the MRI machine if brought in individually, or am I wrong? https://www.google.com/search?q=mri+without+cover&tbm=isch https://www.google.com/search?q=mri+without+cover&tbm=isch
- r2_pilot 2y agoThe engineers have accounted for this and appropriately fasten the individual components to the machine rather than bringing the parts in for assembling the machine while the high powered magnetic field is present.
- slowtokyo 2y agoSo how do the microphones that you use to talk to the tech in the MRI machine work?
- jlarocco 2y agoThese are popular with two-way radios, where they're called acoustic tube earbuds. I'd guess the tube is longer in an MRI, though.
- rjmunro 2y agoTV presenters often use them; presumably the clear plastic tube are supposed to be harder to see.