this post was submitted on 31 Dec 2024
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[–] Zorsith@lemmy.blahaj.zone 50 points 6 days ago (2 children)
[–] SubArcticTundra@lemmy.ml 14 points 6 days ago

I was going to say it's this one

[–] S_H_K@lemmy.dbzer0.com 4 points 5 days ago

Ah now it makes sense.

[–] Midnitte@beehaw.org 29 points 6 days ago (1 children)
[–] SubArcticTundra@lemmy.ml 6 points 6 days ago (1 children)

What does the machine do? Why is there a picture?

[–] Oestradiolo@lemmy.blahaj.zone 15 points 6 days ago (3 children)

It jets a puff of air onto your eyeball to see how the blood vessels react. Big problems if you fail.

[–] Midnitte@beehaw.org 13 points 6 days ago (1 children)

You mean a torture machine, meant to fill you with dreadful anticipation until the moment of horror

[–] Zorsith@lemmy.blahaj.zone 10 points 6 days ago

There's fancy new ones now, no more air puff!

[–] mormund@feddit.org 9 points 6 days ago (1 children)

Different machine, at least in my (unfortunately extensive) experience. The inner eye pressure tester has just a dot, no picture. And it's not that bad, very treatable. But if you miss it too long, yep your blind

[–] joyjoy@lemm.ee 3 points 6 days ago (1 children)

The eye pressure test stresses me out.

[–] ChaoticNeutralCzech@feddit.org 4 points 5 days ago (1 children)

I've been through it several times and I still flinch every time but by then, the machine's laser detectors will have measured how much the eyeball deformed from the precisely controlled puff. Too little indicates a problem that could lead to glaucoma (vision tunneling).

The procedure used to be way worse, the patient would lie down and have ACTUAL WEIGHTS lowered ON TOP OF THE EYEBALL. Of course, they would need to remain still an open-eyed throughout.

[–] mormund@feddit.org 2 points 5 days ago (1 children)

Do you have a source for that? Sounds crazy. At least today you can alternatively measure it with eye drops and a special optical instrument

[–] ChaoticNeutralCzech@feddit.org 3 points 5 days ago (1 children)

Look up indentation (Schiøtz) tonometry. In Eastern Europe, applantation tonometry was developed and used around that time, where the patient was sedated with cocaine and a known-weight cylinder covered in hydroglycerinated Bismark brown solution (basically eye-safe ink) was placed on top of the cornea. Part of the cornea that pressed flat against the tool displaced the ink, which was then stamped on paper to measure the white circle.

Non-contact tonometry was first developed in 1972 by Dr B. Grolman and didn't change much since except now it's digital of course.

[–] mormund@feddit.org 2 points 5 days ago

Damn that is rough, thanks for the reference. Really glad I was born when I was 😅

[–] Cenotaph@mander.xyz 3 points 6 days ago

That or you were holding your breath in anticipation of the puff lol

[–] Jessica@discuss.tchncs.de 11 points 6 days ago (1 children)
[–] jawa21@lemmy.sdf.org 8 points 6 days ago

Thanks. I haven't been to an optometrist in a long time, and this gave me some context.

[–] OmegaLemmy 9 points 6 days ago

I had a lot of help from my personal doctor to actually get LASIK and improve my eyesight tenfold

Thanks bashar Al assadinovic!

[–] rossome@lemmy.ml 1 points 6 days ago

At first I thought it was from this