[HN Gopher] US surgeons perform first whole eye transplant
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US surgeons perform first whole eye transplant
Author : PaulHoule
Score : 174 points
Date : 2023-11-15 15:09 UTC (7 hours ago)
(HTM) web link (medicalxpress.com)
(TXT) w3m dump (medicalxpress.com)
| root_axis wrote:
| Pretty incredible, though I am doubtful of the optic nerve
| regeneration because of the absolutely insane density of the
| nerve fiber. Seems like something that will be beyond the grasp
| of science for the foreseeable future, but the possibility of the
| unexpected is exciting.
| david-gpu wrote:
| _> I am doubtful of the optic nerve regeneration because of the
| absolutely insane density of the nerve fiber. Seems like
| something that will be beyond the grasp of science for the
| foreseeable future_
|
| It's been done quite successfully in mice [0]. Last I checked,
| it was being tested on primates. The method relies on
| activating the Yamanaka factors used in stem cell research.
|
| [0] https://hms.harvard.edu/news/vision-revision
| jessriedel wrote:
| Your link is about gene therapy in the eyes of mice, and is
| specifically a method designed as an _alternative_ to
| transplant:
|
| > "This new approach, which successfully reverses multiple
| causes of vision loss in mice without the need for a retinal
| transplant, represents a new treatment modality in
| regenerative medicine."
|
| And that's just retinal transplant, much less whole-eye
| transplant.
| david-gpu wrote:
| The link provided is also about about a method to produce
| _optic nerve regeneration_ , regardless of whether there
| has been a transplant or not. Unless you have a reason to
| believe that it would not work in the case of a transplant.
| westurner wrote:
| Retina or optic nerve: how do the regenerative methods
| differ?
|
| Visual system > System overview:
| https://en.wikipedia.org/wiki/Visual_system :
|
| > Mechanical: _Together, the cornea and lens refract
| light into a small image and shine it on the retina. The
| retina transduces this image into electrical pulses using
| rods and cones. The optic nerve then carries these pulses
| through the optic canal. Upon reaching the optic chiasm
| the nerve fibers decussate (left becomes right). The
| fibers then branch and terminate in three places.
| [1][2][3][4][5][6][7]_
|
| >Neural: _Most of the optic nerve fibers end in the
| lateral geniculate nucleus (LGN)._
|
| https://news.ycombinator.com/item?id=36912925 , ... :
|
| - "Direct neuronal reprogramming by temporal identity
| factors" (2023)
| https://www.pnas.org/doi/10.1073/pnas.2122168120#abstract
|
| - "Retinoid therapy restores eye-specific cortical
| responses in adult mice with retinal degeneration" (2022)
| https://www.cell.com/current-
| biology/fulltext/S0960-9822(22)...
|
| - "Genetic and epigenetic regulators of retinal Muller
| glial cell reprogramming" (2023) https://www.sciencedirec
| t.com/science/article/pii/S266737622...
|
| - https://en.wikipedia.org/wiki/Tissue_nanotransfection#T
| echni... Ctrl-F "neurons"
|
| Regeneration in humans > Induced regeneration: https://en
| .wikipedia.org/wiki/Regeneration_in_humans#Induced...
| jessriedel wrote:
| I absolutely have a reason to think optic nerve
| regeneration will be less effective in a transplant. In a
| transplant, the nerve has been severed!
| s1artibartfast wrote:
| The article mentions that vision has been at least partially
| restored following transplantation in animals.
| jessriedel wrote:
| I couldn't actually find anything optimistic after a quick
| search though. This 2017 study just looked at the biological
| viability of the eye, not function:
|
| https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5417899/
|
| And indeed, a popular article from a few days ago has this
| quote:
|
| > "Whole eye transplants in animal models have shown that a
| whole eye transplant is surgically feasible, in that the
| tissue can be transplanted and major blood vessels and nerves
| can be reconnected, and the graft can survive in the short
| term," [ophthalmologist Yvonne Ou] said. "However, no models
| have demonstrated restoration of vision, which is a major
| challenge to the field."
|
| https://www.aao.org/eye-health/news/did-surgeons-just-
| transp...
|
| My guess is that the OP article is just wrong, possibly
| because they confused corneal and retinal transplants (which
| can restore some vision) with whole-eye transplants.
| csdvrx wrote:
| > the graft can survive in the short term,"
| [ophthalmologist Yvonne Ou] said. "However, no models have
| demonstrated restoration of vision,
|
| So the power lines (VCC, GND) are connected, but the IO
| lines are not.
| throw1234651234 wrote:
| I thought we just recently learned to sort-of, kind-of
| reconnect nerves. The solution for spinal tears was essentially
| to bluetooth (literally device on one side of tear and one on
| the other) data between torn spinal cord, and this was a huge
| accomplishment.
|
| So, in short, this seems to be a bionic glass eye in the short
| term? Still cool.
| Sohcahtoa82 wrote:
| > A team of surgeons in New York has performed the world's first
| transplant of an entire eye in a procedure widely hailed as a
| medical breakthrough, _although it isn 't yet known whether the
| man will ever see through the donated eye._
|
| That's an important bit to know, and I imagine there will be a
| lot of people reading just the headline and not realizing that
| sight has not been granted with this transplant.
| freedomben wrote:
| Indeed, if they just slapped it in there like a modular
| daughter-card and hooked it up the the power supply (blood,
| etc) but it doesn't actually work for what most people consider
| eyes to be most useful for, it's a significant datum that
| radically changes the interpretation. Still cool, but important
| detail.
| furyofantares wrote:
| I think maybe the reason people will read the headline and
| expect a fully functional eye is because most people will
| drastically underestimate what an incredible feat this is. It
| isn't much of a stretch to say eyes are a part of the brain
| that's sticking out.
|
| If a headline talked about the first dorsal amblugda
| transplant (or some non-made-up component of the brain's
| anatomy), I would not expect it to be functional. I would be
| very impressed that they managed to "slap it in there like a
| modular daughter-card and hook it up the the power supply"
| although it wouldn't occur to me to use a metaphor that makes
| it sound in any way simple.
| standardUser wrote:
| I imagine a lot of people reading the comments won't realize
| that this same procedure has restored partial sight in animals.
| qup wrote:
| If we stick a visual input into the brain, it's almost
| certainly going to use it in some capacity, even if it
| doesn't become "normal" vision.
|
| Maybe re-introduce some neuroplasticity...
| reactordev wrote:
| Given the signal isn't blocked by scar tissue on nerve
| endings, I see this happening. The brain is amazing. It can
| reroute. It can form new routes given stimulus and a need.
| I have no doubt that if the patients nerve endings are good
| and the eye was attached proper (sounds like it was) then
| it's a matter of time before the brain reconnects the
| shutdown pathways.
|
| It takes some effort, some real effort, on the patients
| part though. Meditation. Visualizing the brain making the
| connections. Eating right. Exercising. And healing.
|
| Not guaranteed but the best environment is crucial to
| regain mobility/ability.
|
| This is coming from someone who has broken their back,
| their legs, arms, fingers, wrists, skull, and a few broken
| toes. Obviously not all at once. I have had 1 surgery, the
| rest I declined. The body knows itself. Don't get in the
| way of it correcting itself. Just provide the best
| environment you can. You may not be able to reach your bum
| today, but you will.
| karaterobot wrote:
| > The transplanted left eye appears very healthy, said retinal
| ophthalmologist Vaidehi Dedania. It has a good blood supply, is
| maintaining its pressure, and is generating an electrical
| signal, though James is not yet able to see. "But we have a lot
| of hope," she added.
|
| Not that it didn't work, but that it's too early to tell.
| Fingers crossed.
| Liquid_Fire wrote:
| Though later on the article also says, less optimistically:
|
| > Given the time that has passed since the surgery,
| Washington said she did not think it likely that James's eye
| would regain vision, but "I never say something is
| impossible," she added.
| neogodless wrote:
| Also see previous discussion:
|
| https://news.ycombinator.com/item?id=38209680
|
| _Doctors complete first successful face and whole-eye
| transplant_ (scientificamerican.com) 5 days ago | 70 comments
| aurizon wrote:
| As qup says, >>Maybe re-introduce some neuroplasticity... Would
| the Yamanaka factors and brain-nerve remapping(that it might
| invoke) be a path?
| sethhochberg wrote:
| Also amazing to read in the article that this was done as part of
| a face transplant which is now considered standard care for
| severe disfigurement instead of experimental! It doesn't feel
| like all that long ago we were reading about the first successful
| face transplant ever performed.
|
| Love the patient's attitude about already getting a new face, so
| why not try the eye too and see how well it works since he'd be
| doing transplant care regardless. Seems like he completely
| understands it might not work fully or at all, but that there was
| stuff to be learned regardless.
| graphe wrote:
| The amount of elective cosmetic surgery to the body and face
| this last decade and the normalization of it has made that
| statement sounds too obvious to me.
| itishappy wrote:
| "Transplant" is the critical factor here. Introducing foreign
| tissue is significantly more complicated than shuffling
| around native tissue.
| graphe wrote:
| You're right I confused it with grafting. I thought that
| facial transplants meant grafting 'extra' skin onto the
| face. Still think there's carryover from other fields like
| plastic surgery and probably cancer treatments to make this
| easier.
| spondylosaurus wrote:
| Plastic surgery isn't inherently cosmetic; plastic
| surgery training includes things like facial
| reconstruction/burn grafts, plus some minor training in
| related cosmetic procedures. Cosmetic surgery training
| OTOH focuses _strictly_ on cosmetic procedures.
|
| It's not uncommon for a single doctor to be both a
| licensed plastic surgeon and a licensed cosmetic surgeon,
| but they are distinct licenses.
| hwillis wrote:
| It's not the standard of care, a doctor said it SHOULD be
| standard of care. Transplants for nonvital organs are very
| rare. It has been possible to transplant things like arms and
| legs for a long time- see Gudmundur Felix Gretarsson, who is
| able to feel things in his arms now and use them for light
| tasks.
|
| https://en.wikipedia.org/wiki/Gu%C3%B0mundur_Felix_Gr%C3%A9t...
|
| But maybe 100 people total have transplanted arms. They are
| rare because insurance doesn't cover them; medically they're
| considered investigational. Growing nerves back is still a
| complete crapshoot, and you'll certainly never get back normal
| function.
|
| That's a pretty significant issue, because even arm transplants
| compromise your life in new and terrible ways. You're required
| to take prednisone, ciclosporin etc for the rest of your life.
| You trade off one crippling disability for another- a massively
| compromised immune system. Potentially that can kill you, if
| you get sick and are unlucky.
|
| You can open a door and use a broom with a hook. You get very
| little quality of life from feeling tingles in your elbow. Is
| that worth risking your life and taking expensive steroids
| every day which can drastically change the way you think and
| feel? Probably not.
|
| Is it worth it to be able to hold hands with your wife? To be
| able to feel the heat of a coffee mug? To not need help putting
| your arms on? Medical literature does not typically value those
| things. Objectively they're small, momentary inconveniences.
| Many, many people are happy without them. They might mean the
| world to others.
|
| In cases like the OP it's cut and dry, IMO. Look at him (image
| fairly disturbing):
| https://static.scientificamerican.com/sciam/assets/Image/202...
|
| That tissue on his face, even after 50+ surgeries, is
| agonizing. There just isn't enough skin and what's left is
| fragile. Cuts and blisters get pulled open and don't want to
| heal. Every movement sucks. That person would not mind wearing
| someone elses face; they aren't wearing their own face any
| more. It's completely unsurprising that their quality of life
| is improved, even with all the immunosupressants.
| irrational wrote:
| What if a colorblind person received a non-colorblind person's
| eyes? I wonder if the brain would have trouble with the new color
| information?
| graphe wrote:
| I spoke to Sunwoo Kwon about human optics.
| https://scholar.google.com/citations?user=3Lrjfs4AAAAJ&hl=en
|
| He deals with restoring partial sight when normal methods fail,
| and talks about primative eye tracking like the ability to sense
| direction can still be signaled even if there is no "sight".
| Blind cave fish for example still use their eyes to track even
| with no vision. It is possible the eye can not "see" but still
| signal.
| everforward wrote:
| I think this is the relevant paper [1]. It appears to be about
| the inverse problem, though. The guy in the article has a
| healthy brain but damaged eyes, so his brain isn't getting any
| visual signals to interpret. The patients in the paper have
| healthy eyes but damaged brains, so their brain is getting
| visual signals but it can't interpret them.
|
| That is interesting regardless. It's like the brain lost the
| ability to process visual data into images, but is still able
| to derive some information from it. Makes me wonder how many
| variations of sight there are. Is it possible to detect motion
| without sight? Or to have depth perception without sight? I
| guess depth perception without sight would be like complete
| colorblindness, almost like lidar.
|
| 1: https://elifesciences.org/articles/67573
| mogadsheu wrote:
| Does anybody remember that movie Minority Report with Tom Cruise?
|
| Eye transplants were available in that realist dys/utopian
| future.
| encoderer wrote:
| This was the first movie I tried to pirate. I think I was
| downloading in divx format from LimeWire or Kazaa over my 1mbs
| cable modem.
|
| I came back a couple hours later and I had about 20 minutes of
| the movie that I could start to play while the rest downloaded.
| I remember it started so hard that I just ended up leaving and
| going to the movies to see the rest of it.
|
| I realized then that damn these movie studios are doing it all
| wrong.
| baby wrote:
| It's the best scifi movie out there by far. Of course everyone
| remembers it.
| dudul wrote:
| Should have ended after he gets put in jail. But no,
| Spielberg had to Spielberg and shoe horn a happy ending.
| tibbydudeza wrote:
| The retina technically is part of the brain. It does all sorts of
| signal compression and visual pre-processing before sending the
| signal (not pixels) to the visual cortex via the optical nerve.
|
| Somebody made some calculations on Quora - it is a factor of 6600
| to 1 compression ratio or 40 exabytes from the rod/cone cells
| down to 6 petabytes along the optic nerve.
| cbeach wrote:
| Interesting stats. Could you elaborate on the data you
| mentioned please? What does the 40 exabytes represent? Is that
| a single "frame" of an image captured by the eye? Or perhaps
| its data per second?
| norwalkbear wrote:
| Tldr: no sight
| pionar wrote:
| _yet_
| xchip wrote:
| What is the ETA?
| neogodless wrote:
| We have to wait and see.
| hwillis wrote:
| It has been 6 months. This is a CNS nerve, so you'd usually
| expect to see something in 3-6 months. CNS nerves are much
| less likely to heal, and it was 3 months between the eye
| being removed and the transplant.
|
| IMO it seems unlikely that there will be any restoration of
| vision, but having an eye at all is an absolutely
| incredible accomplishment surgically. All those tiny things
| being attached inside the skull is just amazing.
| xchip wrote:
| thanks
| yonatan8070 wrote:
| This is incredible, but I can't help but wonder where they got
| the new part of the face and the eye?
|
| A donor can't just donate that like they can with blood or a
| kidney. Is it only done with donations after death?
| windowshopping wrote:
| almost certainly a post-mortem donation. there's no shortage of
| people dying, after all. 150,000 a day, and not all elderly.
| johntiger1 wrote:
| Unfortunately, very few people opt-in for organ donation.
| Thousands of people die a year waiting for transplants.
| Enginerrrd wrote:
| >Unfortunately, very few people opt-in for organ donation.
|
| Wait, really?
|
| This always seemed like a no-brainer to me. Why would
| people be opposed to this?
| groestl wrote:
| I'm thankful I live in a country where opt-out is the norm.
| hwillis wrote:
| > "The donor hero was a young man in his 30s who came from a
| family that strongly supports organ donation. He, in support by
| his family, generously donated tissues leading to this
| successful face and eye transplant, but also saved three other
| individuals between the ages of 20 and 70, donating his
| kidneys, liver, and pancreas," said Leonard Achan, RN, MA, ANP,
| president and CEO of LiveOnNY.
|
| https://nyulangone.org/news/nyu-langone-health-performs-worl...
| w10-1 wrote:
| Unmentioned is whether the optic muscles were connected and/or
| usable: iris, cilia, 6 motor muscles/nerves to move the eyeball.
| The cosmetic benefit over a glass eye depends entirely on whether
| the eyeball moves somewhat normally, if not the iris responding
| normally.
|
| Beyond that I'd offer zero hope of restoring any kind of visual
| acuity.
|
| The term "Nerve" is used both for the bundle of neurons and for
| each neuron. Virtually all neurons, but particularly those in the
| eye, have a body-mapping to a corresponding area in the brain
| (and in the case of vision, across 2 sets of neurons). For
| vision, these nerves end in a columnar organization such that
| secondary neurons essentially observe these primary ones to
| detect e.g., motion across an axis at that point.
|
| Even if you just clipped one optic nerve bundle and then tried to
| have it grow back together, there's no way you'd get even most of
| the connections right for the million+ neurons. So I see no hope
| for doing that with someone else's eye. So there's no real
| visual-function reason to try the eye transplant.
|
| Worse, transplant drugs generally suppress the body's
| immunological response, in the normal compartments (blood and
| lymph). I'm not sure anyone's really tested transplantation in
| the brain compartment. I suppose an option for rejection is to
| remove the eye, but how much of the nerve would have to be
| removed? How much brain surgery would be require for that?
|
| Or perhaps worse, imagine signals do get through but hugely
| messy. If/since flashing lights and swerving horizons can produce
| headache and nausea, I can't imagine what this visual garbage
| would do.
|
| In this case, I'd be concerned this electrical lineman was caught
| up in the surgeon's desire to make a name for himself.
| thomastjeffery wrote:
| The brain is not a permanently shaped integrated circuit.
| Neuroplasticity could potentially accommodate the difference in
| nerve mapping.
|
| We shouldn't be so bold as to rule out the possibility.
| johntiger1 wrote:
| > caught up in the surgeon's desire to make a name for himself.
|
| Clinical trials often give people a ray of hope and I would
| imagine this trial was done without coercion. Remember that
| insulin, coronary bypass surgery and literally every medical
| treatment today was once experimental.
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