Eyes and Vision

What can I do about a drooping eyelid?

DEAR DOCTOR K: My right eyelid droops and interferes with my vision. What can I do about this?

DEAR READER: The medical term for a drooping eyelid is "ptosis" (pronounced TOE-sis). In severe cases like yours, the drooping eyelid can cover all or part of the pupil and interfere with vision. Every part of our body is constantly tugged on by gravity. And something that is constantly being pulled downward (at least when we are standing or sitting) tends to sag. The eyelid is no exception. The effects of gravity can be exaggerated by any injury that weakens the strength of the eyelid.

What replacement lenses should I chose after cataract surgery?

DEAR DOCTOR K: I'm having cataract surgery in a few weeks. There are so many options for replacement lenses. Which one should I choose?

DEAR READER: I can't tell you which you should choose, since I don't know the specifics of your cataract. But I can suggest how you should think about several options that your ophthalmologist is likely to discuss with you.

How often should I have my eyes examined?

DEAR DOCTOR K: How often should I have my eyes examined? What will the doctor check for during the exam?

DEAR READER: Routine examinations in people without known eye diseases, and who don't have hereditary eye diseases in their families, usually are done by optometrists. They also can be done by ophthalmologists (doctors who specialize in eye diseases). You should have your eyes examined every two to four years between the ages of 40 and 64, and then every one to two years after that.

Can you explain what will happen during LASIK eye surgery?

DEAR DOCTOR K: I've just scheduled LASIK surgery. Can you explain what will happen during the procedure?

DEAR READER: To understand LASIK surgery, you first need to know a few things about the eye and what it does. Basically, your eye is like a camera: It focuses the light coming into it to make a sharp image. That image then is captured on a kind of film (or, in digital cameras, a sensor).

What does it mean if you have elevated eye pressure?

DEAR DOCTOR K: At my last appointment, my ophthalmologist mentioned something about elevated eye pressure. What could this mean?

DEAR READER: Elevated eye pressure is often -- but not always -- associated with glaucoma. Glaucoma is a group of eye diseases that cause vision loss by damaging the optic nerve, which transmits visual information from the eye to the brain.

What is “dry” AMD and what can I expect?

DEAR DOCTOR K: My ophthalmologist has told me I have "dry" AMD. What is this? What can I expect going forward?

DEAR READER: Age-related macular degeneration (AMD) affects the macula, the small part of the retina responsible for sharp, central vision. The retina is the back part of the eye. As light enters your eye, the lens of your eye focuses the light on the retina. The retina then sends signals to the back of your brain. It's there that your brain translates those signals into vision -- the image of the things you are looking at.

What is the best way to treat conjunctivitis?

DEAR DOCTOR K: My daughter's eye is red. Does she have conjunctivitis? If so, what's the best way to treat it? Is there any way to prevent it?

DEAR READER: It could be conjunctivitis, but it also could be several other conditions. If her eye has one bright red area, but she doesn't have discomfort, it could be that a tiny blood vessel has burst. It may sound bad, but it's a simple and common condition that will slowly go away. But if the eye is extremely painful, it could be conditions that actually threaten her vision, including iritis and glaucoma.

What causes under eye bags, puffiness, and dark circles?

DEAR DOCTOR K: Why do I have bags, puffiness and dark circles around my eyes? What can I do about it?

DEAR READER: My Harvard Medical School colleague Dr. Robert Shmerling wrote about this a couple of years ago in the Harvard Health Letter newsletter. Here's some of what he said: Gently pinch the skin under your eyes and give it a little tug. You'll feel that it's a little looser and thinner than skin elsewhere. It's also looser and thinner than it used to be.

I’ve begun to notice “floaters” in my vision, should I be concerned?

DEAR DOCTOR K: At 65, I have begun to notice tiny threadlike shapes in my vision. My doctor calls them "floaters." Should I be concerned?

DEAR READER: "Floaters" describes the dots, threads or cobwebs that we notice drifting across our line of vision as we get older. You're more likely to notice floaters when you are looking at a page of a book, a computer screen or a solid, light background. Floaters move as your eye moves and dart away when you try to look at them.

I’m curious — How do we see?

DEAR DOCTOR K: This isn't a medical question -- I'm just curious. How do we see?

DEAR READER: It all begins with light. Light from the sun, moon, fire or (in the past century or two) from electric lights bounces off an object and enters our eyes. The eye is like a camera. It has a lens that continuously focuses to sharpen the picture. Then the eye sends the picture to the brain, which processes the picture and does the seeing.