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How do MRI Headphones work? (2022)

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Re: How do MRI Headphones work? (2022)

#131

Post by lostlogin »

caseyohara wrote: post #18
djhope99 wrote: post #9

I 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.

I recently got an MRI and the technician asked me what I wanted to listen to on the headphones. I said "Something relaxing, do you have ambient music?". This turned out to be a terrible choice; the music was so quiet I could barely hear it. Earplugs would have been better. I had some in my pocket that I brought but it was too late. So after the claustrophobic panic subsided and I realized I was left in there with not…

Earplugs and music is the discerning choice.

Most (all?) vendors suggest this - they get well over 100db and the vendor headphones are pretty crappy.

Re: How do MRI Headphones work? (2022)

#132

Post by lostlogin »

riahi wrote: post #24
dylan604 wrote: post #13

Earlier quoted context omitted.

What 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…

The RF pulses and field gradients can directly stimulate the peripheral nerves. I have had involuntary muscle twitching triggered by many pulse sequences. It’s not unheard of. It made me more sympathetic for patients who have motion in images. It could be that the particular combination of pulse sequence and their nerves don’t jive and triggers movement. Source: Radiologist (and personal experience in the bore)

If the patient isn’t twitching occasionally, the resolution is too low. We aim to be just below peripheral nerve stimulation threshold.

I’m sort of joking, but if you aren’t ever getting PNS, the machine is not being run very hard.

However the sensation you get in the region being scanned feels more like heating than PNS to me. You notice it more on high SAR sequences, suggesting that might be the cause. PNS just feels like twitching you can’t control, but ones milage may vary as this is anecdotal.

Source: MR radiographer.

Re: How do MRI Headphones work? (2022)

#133

Post by jrd259 »

wiml wrote: post #105
roughly wrote: post #97

Earlier quoted context omitted.

It was! The whole book plays a lot with various types of consciousness. Although that was a bit of a spoiler, so out of respect I'll give a somewhat obfuscated link and just say if you're reading something by Alastair Reynolds right now you should consider that before following the link: https://openlibrary.org/books/OL26809698M (Reynolds' got enough books in his bibliography I don't feel like I'm spoiling anything b…

Ah, I thought this was going to be Karl Schrœder's Permanence , in which (unless I'm confusing it with a different book) a background point is that consciousness is only really useful in some niches, and most spacefaring species eventually lose it.

John Varley had a short story with that idea, too. A spacefaring race that is only conscious when needed. Good sarcastic lecture about how consciousness is overrated by those who have it.

Re: How do MRI Headphones work? (2022)

#134

Post by unscaled »

vidarh wrote: post #90
AnotherGoodName wrote: post #87

Earlier quoted context omitted.

It was united that I most recently encountered this too. It was 2005ish and they flew a 747 with pull down theatre screens and pneumatic headphones on an australia-us flight. Not sure if that was the backup plane or they were just desperately holding out to upgrade the fleet. Having said that anyone that flew just over 30 years ago would have likely used pneumatic headphones and watched on a shared pulled down theatr…

Shared screens was the norm in Europe too, but pneumatic headphones is something I've never seen on a European carrier at all - not at all ruling out some might use them, after all, there are many of them and I've by no means flown them all. I wonder, though if it's another case of tech that may have been skipped by airlines that e.g. didn't add inflight entertainment as early as others and so got to "skip ahead" a g…

I've also don't remember seeing them in Europe when flying as a child during the 1990s. Yes, there were shared CRTs every 10-15 rows or so, but the earphones were your run-of-the-mill electric earphones, usually with a two prong connector.

I have to add these were all international flights (this was mostly pre-Schengen, and in any case I don't believe I've taken a flight between Schengen Area countries until 2023), so I'm not sure if shorter distance flights would have been different. The mid-distance flights (> 2.5 hours) I've taken would generally have in-flight entertainment if it wasn't a budget option. Some of the cheaper flights had no screens (or maybe they had ones, but didn't want to pay for the movie) and still had earphones slots connect to a set of inflight radio stations (that were also available when there was a movie being played, as an alternative).

So yes, it was an arguably "superior" experience with selectable audio, volume buttons and rather crappy drivers directly inside the earphones.

Re: How do MRI Headphones work? (2022)

#135

Post by littlecranky67 »

jerlam wrote: post #95
vidarh wrote: post #90

Earlier quoted context omitted.

Shared screens was the norm in Europe too, but pneumatic headphones is something I've never seen on a European carrier at all - not at all ruling out some might use them, after all, there are many of them and I've by no means flown them all. I wonder, though if it's another case of tech that may have been skipped by airlines that e.g. didn't add inflight entertainment as early as others and so got to "skip ahead" a g…

I haven't seen a inflight entertainment console in a few years of flying. There's a trend for some carriers in the US to remove them since most passengers would rather use their own tablet, phone, or laptop with much higher quality; and the carrier can sell them wifi. https://www.forbes.com/sites/suzannerowankelleher/2019/10/13...

I've recently been on a plane which had some kind of small phone/tablet mount on the back of the headrests so that you could actually pull it down and put your phone/tablet on it to watch a movie. Great UX, because everybody is on their own devices all the time anyway.

Re: How do MRI Headphones work? (2022)

#136

Post by t0mas88 »

vidarh wrote: post #90
AnotherGoodName wrote: post #87

Earlier quoted context omitted.

It was united that I most recently encountered this too. It was 2005ish and they flew a 747 with pull down theatre screens and pneumatic headphones on an australia-us flight. Not sure if that was the backup plane or they were just desperately holding out to upgrade the fleet. Having said that anyone that flew just over 30 years ago would have likely used pneumatic headphones and watched on a shared pulled down theatr…

Shared screens was the norm in Europe too, but pneumatic headphones is something I've never seen on a European carrier at all - not at all ruling out some might use them, after all, there are many of them and I've by no means flown them all. I wonder, though if it's another case of tech that may have been skipped by airlines that e.g. didn't add inflight entertainment as early as others and so got to "skip ahead" a g…

Same experience here, never seen a "tube" type headphone on any European airline, but several carriers used weird headphone plugs so they could still sell you headphones.

Re: How do MRI Headphones work? (2022)

#137

Post by Traubenfuchs »

Ok, 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

Re: How do MRI Headphones work? (2022)

#138

Post by jamiek88 »

projektfu wrote: post #70
astrodust wrote: post #58

Earlier quoted context omitted.

Twelve channels of the weirdest and/or lamest music you'd ever heard in your life, all in a faint, tinny form that makes AM radio sound audiophile quality.

And, if you're lucky on a longer flight, the audio to a film selected to be inoffensive to everyone on the aircraft.

Sometimes in sync!

Re: How do MRI Headphones work? (2022)

#139

Post by t0mas88 »

Aurornis wrote: post #52
FriedPickles wrote: post #19

I 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.

> 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 (ph…

If Bluetooth headphone batteries can produce significant heat for 8 hours we would have discovered a lot of free energy :-)

Re: How do MRI Headphones work? (2022)

#140

Post by rob74 »

vidarh wrote: post #90
AnotherGoodName wrote: post #87

Earlier quoted context omitted.

It was united that I most recently encountered this too. It was 2005ish and they flew a 747 with pull down theatre screens and pneumatic headphones on an australia-us flight. Not sure if that was the backup plane or they were just desperately holding out to upgrade the fleet. Having said that anyone that flew just over 30 years ago would have likely used pneumatic headphones and watched on a shared pulled down theatr…

Shared screens was the norm in Europe too, but pneumatic headphones is something I've never seen on a European carrier at all - not at all ruling out some might use them, after all, there are many of them and I've by no means flown them all. I wonder, though if it's another case of tech that may have been skipped by airlines that e.g. didn't add inflight entertainment as early as others and so got to "skip ahead" a g…

I guess the airlines went with whatever was cheaper? For a while, pneumatic headphones (in a system with 100+ headphones) probably were cheaper overall than electronic ones, but with the constant decrease of electronics prices, by the 1990s they probably were only still there for legacy reasons...
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