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1

It seems to me that really your whole question seems to be much simpler than it seems and it is just "why are eye banks called eye banks when they can't transplant eyes, just bits of them like corneas" The answer is: In the english language and in various cultures, the names of things often have a loose and not entirely accurate relationship to the ...


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In addition to providing tissue for transplant, eye banks also provide tissue from all parts of the eye to medical schools and universities for teaching and research purposes. There are many medically relevant questions that can only be answered by examining human tissue, and eye banks facilitate this research.


14

I used to work at an eye bank so I have a bit of knowledge about this, though some of it may be out of date. There are several aspects to an eye bank. The corneas are one of the primary things that are kept for transplantation. Of course, this will not repair blindness in someone that has problems in other areas of the eye, but corneal transplants are ...


17

You are asking two questions that you think are connected but are actually not. Question 1 - What is the use of eye banks? Answer: It's to store corneas for transplant for people with cornea damage. Question 2 - What use is cornea transplant to a completely blind person? Answer: It depends. If the blindness is due to clouded cornea (several ...


9

No-one can re-implant an entire eye, because the optic nerve has been severed in one who has lost an eye. A cornea can't be grafted to a glass eye. But blindness isn't only caused by loss of the entire orbit. It's also caused by cloudy corneas, which is the purpose of eye-banks. The optic nerve is a cable of nerve fibers that carry visual information from ...


2

The eyeball is basically the sclera that surrounds the delicate inner structures of the eye (see wiki on the eye). The cornea is the transparent window in front of the pupil that transmits light to the retina. It needs replacement when it turns opaque, often due to damage or infections. The cornea can be replaced on its own, without the need for ...


1

Technology is not advanced enough to achieve receptor-specific stimulation. Regarding your defined needs: 1) Identifying M cones: It is already challenging to distinguish cones from rods in the retina (Turpin et al, 2011), let alone identify the three classes of cones. 2) Your retinal-mosaic image would theoretically be possible, although very small pixels ...


0

Very nice question! You are right, in that small pupils will help to reduce the blurriness of vision caused by refractive errors. Removal of the lens (aphakia) results in farsightedness. It is caused by a focus point that falls behind the retina as the absence of the lens prevents focusing of the image, causing a blurred image. The amount of blur is ...


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The capture area of the eye is a bit fuzzier and harder to define than that of a camera. A camera captures consistent, fully detailed data right up to the edge of its sensor, and no data at all beyond it. Captured data is clipped by an ideally uniform sensor, augmented a bit by the lens, and is well-defined during design and manufacturing. The eye can ...


4

Vision deteriorates for both reasons, but I'm not quite sure how to separate the effects of aging from wear and tear. Cataracts are the leading cause of blindness in the world. Ways in which environment (which falls under the category of wear and tear in my book) affects cataract formation: UV light: people living at high altitudes (e.g. Tibet) have ...


0

Interesting question. I concur with @Chris. Color constancy and size constancy are neural mechnisms. As an analogy: they are photoshopped representations, i.e., subjective representations manufactured by higher-level visual processing. However, focus is determined by optics. An out-of-focus picture, to push the analogy, cannot be fixed by fotoshop, nor the ...


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I am colorblind, but I did not know that before I was 22 (!!). I got to know it by doing the Ishihara test. There are other tests you can do to test for colorblindness, such as the reverse colorblindness test (http://www.cs.unm.edu/~aaron/creative/colorTest.htm), where a "normal vision" person will not see the two patterns shown there. Anyway, there is no ...


3

I have had a very difficult time finding information that was well-written and what you were looking for. So, I did my best! From what I have read it takes about four months - everyone is a little bit different and some take longer! Those of us with no visual impairment that try to learn it have no advantage and maybe a slight disadvantage with learning ...


0

Interesting question. But from a philosophical point of view - What does upside down mean on a flat cortical surface? The fact that the retinal input is flipped does not mean it has to be 'de-flipped' in the cortex. There are retinotopic projections to the cortex that code corresponding parts in the retina. It needs no flipping.



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