Vision

Vision Articles

Dry eyes and what you can try

If our eyes are healthy, we're producing tears all the time and not noticing it very much, if at all. We need a thin layer of tears to lubricate, protect, and nourish the fronts of our eyes. That "tear film," as ophthalmologists call it, isn't just salty water but a complex mixture of substances produced and maintained by several glands and structures in and around the eyes. If the tear film degrades, we experience dry eyes. The symptoms are familiar to many of us: irritation, scratchiness, a burning sensation. Sometimes vision is affected, getting blurry off and on. Mild cases — and many are — can be treated rather easily with any of over a dozen different over-the-counter products. In a change from the past, dry eyes are now seen as having an inflammatory component, not just a loss of moisture. To combat the inflammation, some ophthalmologists prescribe drops that contain a very small amount of cyclosporine if the over-the-counter products don't work. Cyclosporine is a drug that organ transplant recipients take to suppress the immune system so the organ is less likely to be rejected. Dry eyes used to be thought of as a simple problem of not enough tear production, too much tear evaporation, or some combination of both. Dry eyes may still begin that way, but now the thinking is that localized inflammatory processes get started as the tear film loses moisture. More »

Blinded by the night

Poor night vision is the result of changes in the pupil, lens, and retina. Does eating carrots help? Probably not for well-nourished Americans. It's been said that the eyes are the windows to the soul. At a more mundane level, they also say a lot about how old we are. With advancing years, we're prone to a number of serious — and less-serious (but bothersome) — conditions of the eye. The prime example of a serious age-related eye problem is macular degeneration, a retinal condition that's a leading cause of legal blindness among people over age 55 in the developed world. Age-related nuisances include a falloff in tear production that results in drier and itchier eyes. Eyelids also droop and sag, like other body parts. And starting around the fifth decade, almost all of us suffer from presbyopia (Greek for "old sight"), an inability to focus on objects close to our eyes. (Locked) More »

What to do about cataract

For people with cataracts, surgery is common and safe, and is typically covered by insurance. Depending on need and other eye issues, various types of lenses are available. More »

Emergencies and First Aid - Removing a Speck From the Eye

Occasionally, an eyelash or speck of dirt gets into the eye and causes irritation. If tears that form do not wash out the object, it can sometimes be removed by pulling the upper eyelid down over the lower eyelid. The lashes of the lower eyelid may brush out any foreign object that is caught under the upper lid. If this does not work, try either of the procedures described below. Place a cotton-tipped swab behind the upper eyelid and carefully roll the eyelid back onto it. If you can see the object, remove it with the moistened end of another cotton swab or a facial tissue. More »

When You Visit Your Doctor - Macular Degeneration

Have you noticed a change in vision in one eye or both? Do you have trouble reading, even with reading glasses? Do you have difficulty seeing fine details? Do you see a gray patch in the middle of the words when you read? Do straight vertical lines appear "wiggly" when you look at them? Is your side or peripheral vision affected? Do you have diabetes? Do you smoke? Do you have a family history of macular degeneration? The inside of your eye, using an ophthalmoscope (see p. 417) Referral to an ophthalmologist (eye specialist) who will do a complete eye exam with drops to dilate your pupils.   More »

Understanding Botox Injections

With the recent nod of approval from the Food and Drug Administration (FDA), the popularity of Botox injections has surged. Spas, shopping malls, walk-in clinics and even parties advertise the availability of this age-defying treatment. Even before FDA approval, the use of Botox was on the rise, increasing 61% between 2000 and 2001, according to the American Society of Plastic Surgeons. Botox, the trade name for botulinum toxin type A, is used to lessen the telltale signs of aging by softening frown lines on the forehead and brow, crow's feet at the corners of the eye, and other wrinkles. But what is this toxin, how does it work, and who should be administering the procedure? Botulinum toxin type A is one of several proteins secreted by the bacterium Clostridium botulinum. These proteins are neurotoxins; they attack nerve cells and paralyze the affected muscles. Ingestion of botulinum toxins causes the infamous food poisoning botulism. But when the purified form of botulinum toxin type A is injected into the muscles below the skin in very low doses, the result is a reduction in wrinkling. More »

Inside the Eye: From Laser Surgery to Macular Degeneration

Only a few years ago, having imperfect vision simply meant that you went to the eye doctor, got fitted for glasses or contact lenses, and went on your merry way. But now, there's an array of laser surgeries to choose from, each with a slightly different procedure to accommodate particular vision problems. In general, laser eye surgery modifies the cornea, the clear covering of the front of the eye that bends (or refracts) light rays as they enter the eye. For clear vision, the cornea must have the correct shape to focus light rays precisely on the retina at the back of the eye. If the cornea is too steep, too flat, or irregular in shape, the image focuses either in front of or behind the retina — hence, blurry vision. Eyeglasses or contact lenses can compensate for this problem by increasing or reducing the angle of light as it enters the eye. In 2000 the U.S. Food and Drug Administration approved a procedure, laser thermal keratoplasty (LTK), and it approved another in April 2002 called conductive keratoplasty (CK), which is specifically used to correct farsightedness. The most common procedures are photorefractive keratectomy (PRK) and Laser-Assisted In Situ Keratomileusis (LASIK). As time and experience advances, these techniques become ever more precise and predictable. More »