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PeteMC
05-08-2017, 06:46 PM
I know this is a bit of a nasty question but exactly how tough is a human eyeball (while still in the head). Is it possible for someone to burst another persons eyes with their hands, say by pressing their thumbs hard enough into them, or would you need to use a sharp implement of some sort? The subject is alive and conscious but restrained, possibly with clamps if needed.

Thanks in advance!

be frank
05-08-2017, 06:51 PM
Eyeballs are damn tough. The cornea is surprisingly leathery, and the sclera (the white) even more so. Something sharp and directly jabbed (with force) is probably your best bet. FWIW, the ideal diameter for an object to puncture an eyeball is 3mm. :)

be frank, who has actually done this (though not on a living subject).

PeteMC
05-08-2017, 06:53 PM
Eyeballs are damn tough. The cornea is surprisingly leathery. Something sharp and directly jabbed (with force) is probably your best bet. FWIW, the ideal diameter for an object to puncture an eyeball is 3mm. :)

be frank, who has actually done this (though not on a living subject).

Thank you! Mildly intrigued that you have actually done this... :)

be frank
05-08-2017, 06:57 PM
Thank you! Mildly intrigued that you have actually done this... :)

*cough*

Um, yeah. I've also severed heads, but that's a story for another day. :)


eta: Oh, and in case you need it, the clamp you use to hold an eye open is called a speculum. (Assuming you want something more fancy than toothpicks, that is).

Albedo
05-08-2017, 06:57 PM
Hah, I was about to say 'page Be Frank'. Just ... don't ask too many questions about her old life.

be frank
05-08-2017, 07:02 PM
Hah, I was about to say 'page Be Frank'. Just ... don't ask too many questions about her old life.

;)

Sadly, not such an old life. Though tomorrow's patients will probably be relieved I've given up being all stabby-stabby with eyeballs.

Perks
05-08-2017, 07:04 PM
*reads thread* *faints*

CameronJohnston
05-08-2017, 07:12 PM
Just have them digging their nails into the eyeball, Pete. Sorted!

Los Pollos Hermanos
05-08-2017, 08:55 PM
I remember trying to dissect a sheep's eyeball (obtained from a local butcher) during a GCSE biology lesson back in the day. We were given blunt scalpels* which didn't even dent the sclera. We were really surprised by how tough it was, although it makes perfect sense. The eyeballs kept "jumping" out of our trays and we ended up flicking them around the floor.

I've got to teach this to two year 10 (9th grade equivalent) classes next week - should be interesting!

* - I went to a girls' grammar school - we were hardly budding serial killers!
Well... :evil

Tazlima
05-08-2017, 09:44 PM
I remember trying to dissect a sheep's eyeball (obtained from a local butcher) during a GCSE biology lesson back in the day. We were given blunt scalpels* which didn't even dent the sclera. We were really surprised by how tough it was, although it makes perfect sense. The eyeballs kept "jumping" out of our trays and we ended up flicking them around the floor.

I've got to teach this to two year 10 (9th grade equivalent) classes next week - should be interesting!

* - I went to a girls' grammar school - we were hardly budding serial killers!
Well... :evil

Eyeballs are indeed far tougher than one would expect. If you really want a feel for what's possible and what's not, you can always pick up a couple from the butcher shop and actually try poking them with stuff (lol, ew). The tactile element may help you come up with some good similes too.

The other thing to take into account is how much eyeballs move around. They are spherical, after all. I've assisted with a few eye removal surgeries in dogs, and just holding the darn things still is a challenge in and of itself. If you shove something into an eye socket, it may pierce the eyeball, but it also might just push it aside.

Bolero
05-08-2017, 10:42 PM
One caution on "eye balls are really tough" - yes they are, but retina are not. The eyeball can survive a nasty blow intact but stop functioning properly due to detached retina. Detached retina can come from deceleration and the like. Not of concern to OP, but thought worth mentioning for other people wanting to know about damaging eyeballs.

snafu1056
05-08-2017, 10:57 PM
Now I feel like the only person here without hands-on eyeball experience. I've lived such a sheltered life.

Mark HJ
05-08-2017, 11:26 PM
I remember trying to dissect a sheep's eyeball (obtained from a local butcher) during a GCSE biology lesson back in the day. We were given blunt scalpels* which didn't even dent the sclera. We were really surprised by how tough it was, although it makes perfect sense. The eyeballs kept "jumping" out of our trays and we ended up flicking them around the floor.


I've got to teach this to two year 10 (9th grade equivalent) classes next week - should be interesting!


* - I went to a girls' grammar school - we were hardly budding serial killers!
Well...


Yup, likewise - tough little devils, and hurt like crazy when you get hit by one from a slingshot across the lab. (Half-dissected kidneys dropped in your jacket pocket are quite civilised by comparison.) So far as I recall, we were given reasonably sharp scalpels, but it was still hard work.


I went to a boys' grammar school - not sure how we stood as budding serial killers. Perhaps these biology classes ought to be treated as a diagnostic tool for undesirable tendencies - put the kids in a room with miscellaneous body-parts and sharp implements to see what happens.



*reads thread* *faints*

Stay with us. This is important stuff and positively character building.

(And on a very positive note, they started letting girls come to our school, and when I went back for the 20 year reunion I learned that the girl who was seriously top of my year in A-level science is now a consultant eye surgeon.)

PeteMC
05-09-2017, 01:19 AM
I love this place and everyone in it so much :ROFL:

Snitchcat
05-09-2017, 05:07 AM
Love this thread, lol! Very cool info. Thank you! :)

MadAlice
05-11-2017, 06:00 PM
This thread is indeed fascinating. One day I'd like to walk into a butcher shop and say "Pardon me, do you have any spare [weird body part]s? I'd like to poke some."

CWatts
05-12-2017, 12:39 AM
Love this thread, lol! Very cool info. Thank you! :)


This thread is indeed fascinating. One day I'd like to walk into a butcher shop and say "Pardon me, do you have any spare [weird body part]s? I'd like to poke some."

I know, right?

"Slicing up eyeballs, oh oh oh....!"

Mark HJ
05-12-2017, 12:57 AM
This thread is indeed fascinating. One day I'd like to walk into a butcher shop and say "Pardon me, do you have any spare [weird body part]s? I'd like to poke some."
They probably wouldn't even blink if there was a school nearby. Thinking back, we did dissection of heart, eye and kidney, and the teacher had a single set of lungs to do a demo with, and all of the 'raw' materials must have come from a local butcher.

Aged thirteen or fourteen, I helped with 'disposal' of the hearts. Our pet cat thought she was in heaven for days - none of that tinned rubbish, but real meat from a recognisable animal (even if she'd never actually seen one - they were probably sheep or pig).