9
votes
Accepted
When someone with glaucoma sees rainbows around lights, what exactly is happening physically?
The so-called halos are typical for spikes of intraocular pressure rise in high-tension glaucoma (or ocular hypertension) forms, most often in melanin-dispersion syndrome (MDS, or pigment-dispersion ...
- 781
8
votes
Will eye floaters ever disappear?
In general any cellular material within the vitreous may cause eye floaters, for example red blood cells as a result of hemorrhage and white blood cells as a result of infection or inflammation. So ...
- 4,695
6
votes
Accepted
Long-term effects of lens removal as the vitreous ages?
...it seems possible that with aging, as the vitreous becomes less distinct from the aqueous, some of the vitreous might end up draining through the same duct that the aqueous drains through, in an ...
- 8,870
5
votes
Accepted
Outcomes and risks of LASIK surgery
Post-operative complications include the following:
Visually significant wrinkles or striae in the flap (1%)
Dislocated flap (early postoperative period)
Infection (early postoperative period; very ...
- 198
5
votes
Accepted
How to reduce the side effects of wearing contact lens?
Questions 1-2
Unfortunately, the answer to these depend on the exact brand and line of contacts used. For example, here is a long list of silicon hydrogel lenses, and how long they last. Here is ...
- 304
5
votes
Accepted
What causes optical floaters to be more or less visible?
[S]ometimes they become more prominent again, usually for a few minutes at a time. Is this a difference in perception (something is causing me to notice them more) or a difference in placement (they'...
- 8,870
4
votes
Accepted
Astigmatism eyeglass lenses -- how much distortion is normal?
According to my eye doctor, this much distortion is not normal.
He checked the strength of my glasses and they were not made according to the prescription: the OS astigmatism correction was -0.50 ...
- 321
4
votes
Accepted
What is the function of the collagen fibres in the vitreous body of the human eye?
Collagens are a family of fibrous proteins (as opposed to globular proteins like enzymes and hormones and membrane proteins like cell receptors) that form part of connective tissue. Thus they are ...
- 2,341
3
votes
Will eye floaters ever disappear?
The source does not explicitly tell the long-term story, but I presume that since those particles are actual matter inside your eye (due to the ageing process as your body slowly disseminates), then ...
- 155
3
votes
why is it not allowed to take aspirin based medicines before a day and after a week of cataract surgery?
Aspirin has a "blood thinning" effect; it inhibits platelet aggregation. Therefore, it gives a higher risk of bleeding in the period surrounding the surgery.
I have not found a review about ...
- 431
3
votes
Accepted
Safe and state-of-the art method of laser vision/eyesight correction/surgery?
Brief description:
LASEK and LASIK - cut a flap in the eye, use a laser to remove material underneath to reshape the lens and correct vision. LASIK has been around for a while, so there have been a ...
- 304
3
votes
Is the blue light emitted by computer monitors deleterious for the human eyes?
Is the blue light emitted by computer monitors deleterious for the human eyes?
No.
UV from the Sun (or other strong UV sources, such as germicidal bulbs) is harmful.
Blue light from a computer ...
- 221
3
votes
What effects would aspheric contact lenses have on eyes without astigmatism?
A toric lens is the type that is used to treat astigmatism, not an aspheric lens. An aspheric lens is primarily designed to correct for the spherical aberration of the contact lens itself, the ...
- 237
3
votes
Accepted
macular insult during optic neuritis
Optic neuropathy vs optic neuritis
Stat Pearls (Guier and Stokkermans 2021. NBK557853) notes that:
A wide range of conditions including infections, trauma, vascular insufficiency, metastases, toxins, ...
- 2,928
2
votes
Why do optometrists recommend dilation when the power of a lens can be measured even by a ruler?
The value of dilation of the pupil far outweighs the inconvenience.In fact, I'd offer that if an exam is done without it, you potentially lose the following:
--full access to all the structure of the ...
2
votes
Is the common saying that sitting close to a screen regularly can cause short-sightednes backed by medical science?
There is certainly an association between reading at short distances and myopia. Here's an article that suggests a possible mechanism: Reading and Myopia: Contrast Polarity Matters Basically, they ...
- 991
2
votes
Why do the eyes need to be closed during sleep to regain moisture?
Tears are very complex fluids. Their job is to lubricate, moisturize, and oxygenate the corneas and inner eyelids, to be antibiotic/antiviral, to break down byproducts, etc. They're continually ...
- 345
2
votes
Rationale for Pilocarpine instillation after retrobulbar haemorrhage
Retrobulbar hemorrhage (RH) is (Johnson et al., 2009).
an ocular emergency resulting from arterial bleeding in the orbital cavity behind the eye. Because the orbit is a relatively fixed space, ...
- 6,124
2
votes
Which nerve inflammation can affect vision other than the optical nerve itself?
The vision can be sharp when the light is focused exactly on the retina, not in front or behind it. This is enabled by the constant eye bulb length and the ability of the lens to accommodate to near ...
- 15.7k
2
votes
Accepted
Is there a convenient self test for Glaucoma?
Disclaimer: I have no formal medical or vision science training. Please point out any factual errors.
My test is based on the idea that Glaucoma is indicated by pressure on optic nerve, which one may ...
- 603
2
votes
What is the angular resolution of the 'ideal' human eye?
In general, resolution varies with distance, but when expressed as angular resolution this takes distance into account; the minimum distance between two points that can be resolved will increase in ...
- 2,341
1
vote
Outcomes and risks of LASIK surgery
Risks of LASIK (Laser-Assisted in situ Keratomileusis) can include:
Vision loss due to infection,
The researchers calculated the risk of significant vision loss consequence of LASIK surgery to be ...
- 4,695
1
vote
Accepted
Naturally improve eyesight
Ps:myopia is condition your cousin is having most likely.
children's bodies grow, so do the eyes, which may cause a gradual increase in myopia. And just as bodily growth can be in uneven spurts, the ...
- 198
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