nearsightedness Archives - Page 2 of 4

Why do LASIK, PRK, SMILE, and other corneal refractive surgery cause ectasia and other sight-threatening problems even with the most modern lasers?

All of these procedures work by removing tissue, leaving the cornea permanently thinner. This intrinsically stresses the cornea's structural integrity: these procedures work by weakening the cornea optically -but hopefully not structurally (or at least not very much). This is exactly the opposite of what...

in Uncategorized by woodhamseyedev 07 Apr 2024

How is it possible that one eye can be both myopic and hypermetropic?

I wonder if you mean to ask "How can one eye be both nearsighted AND farsighted." Unless one is talking about mixed (compound) astigmatism, you can't actually have a myopic (nearsighted) AND hyperopic (also called "hypermetropic") eye. But you can be nearsighted AND farsighted. There are TWO types of what people call farsightedness: hyperopia...

in Uncategorized by woodhamseyedev 24 Mar 2024

Why are some eyes deep set and others seem so big they bulge?

People have different size globes (eyeballs) which is often an indicator of being near- or farsighted (myopic and hyperopic). Hyperopic eyeballs are almost by definition smaller than normal, having failed to grow to the normal size (+23.0 mm). While vision can be normal in their younger...

in Uncategorized by woodhamseyedev 10 Mar 2024

Is it the eye that actually determines what we see or the brain that interprets it for us or tries to process it?

Is it the eye that actually determines what we see or the brain that interprets it for us or tries to process it? The eyes can be open but, lack the ability to see even when observing things. Are eyes really what people use to...

in Uncategorized by woodhamseyedev 10 Mar 2024

Why do short-sighted people need glasses for up-close vision if they have difficulty with seeing things far away?

Myopic (near- or short-sighted) eyes are typically a larger diameter than "normal" eyeballs. The focusing parts of the front of the eye (cornea, natural lens, and pupil) do not "know" this, so they focus a distant object too soon inside the eye: the image is in...

in Uncategorized by woodhamseyedev 25 Feb 2024

How close can someone see without reading glasses after cataract surgery if their distance vision is 20/20 and they have monofocal intraocular implants in both eyes?

Strange as it may sound, the answer depends on what you have been used to before you had the cataract/IOL surgery. A myopic (nearsighted) person typically always had good near vision with or without glasses. So losing most of that, despite now being able to see 20/20 at...

in Uncategorized by woodhamseyedev 25 Feb 2024

How long will floaters go on? I had cataract surgery 4 years ago. I’ve had floaters for the last three years. What is your experience?

There has been a gradually increasing number of patients in my practice that comment on or complain of vitreous "floaters" after cataract/IOL surgery. The surgery, of course, did not cause the floaters. The reason is that as intraocular lens surgery (whether for purely cataract or for...

in Uncategorized by woodhamseyedev 11 Feb 2024

Can I convert my astigmatisms lenses into normal lenses? My prescription is right eye D: -2.50 CYL: -0.75 and left eye D: -2.25 CYL: -0.75 Thank you!

I assume you mean to get an otherwise equivalent glasses Rx, but without any astigmatism correction? If so, yes, it is quite easy to determine the "spherical equivalent" Rx. You take ½ the amount of cylinder (astigmatism correction) and add it to the spherical component...

in Uncategorized by woodhamseyedev 11 Feb 2024

If a person has an -11 Diopter prescription for glasses, what is that in 20/20 vision… numbers?

People often get confused about measuring vision when they try to compare their glasses prescription with some distance visual acuity measurement on a Snellen type eye chart. It would be nice if there were a corresponding Snellen letter acuity for each diopter of nearsighted correction...

in Uncategorized by woodhamseyedev 28 Jan 2024

How has cataract surgery changed in the last 20 years?

Cataract surgery has changed tremendously over the past 20 years or. And it is almost unrecognizable now when compared to how the operation was performed when I started my training over 40 years ago! Cataract surgery was originally an operation to remove the cloudy opacity visible...