Health Watch

Common eye conditions

When it comes to signs of eye disease, people are blind to the facts. A recent survey showed that while nearly half (47%) of Americans worry more about going blind than losing their memory or their ability to walk or hear, almost 30% of those surveyed admitted to not getting their eyes checked.The following are signs and symptoms of some of the most common eye diseases.
Anatomy of the Eye
The anatomy of the eye is complex. The main structures of the eye include:
Cornea: clear tissue in the very front of the eye
Iris: colored part of the eye surrounding the pupil
Pupil: dark hole in the iris that regulates the amount of light going into the eye
Lens: small clear disk inside the eye that focuses light rays onto the retina
Retina: layer that lines the back of the eye, senses light, and creates electrical impulses that travel through the optic nerve to the brain
Macula: small central area in the retina that allows us to see fine details clearly
Optic nerve: connects the eye to the brain and carries the electrical impulses formed by the retina to the visual cortex of the brain
Vitreous: clear, jelly-like substance that fills the middle of the eye
As you read this slideshow you may need to refer to this illustration for reference.
Glaucoma is a group of eye diseases that develop due to elevated intra-ocular pressure (IOP) within the eye. The increased pressure affects the optic nerve and may cause vision loss. Glaucoma is classified either as open-angle (the more common form that is usually painless) or angle-closure glaucoma (which often occurs suddenly and is associated with pain and redness of the eye).
In the early phases of glaucoma there are often no symptoms. By the time vision is affected, the damage is permanent. Progression of glaucoma can be slowed or halted with eye drops, laser treatments, or surgery so early diagnosis is key.
People with a family history of glaucoma, the elderly, and African-Americans are at increased risk of the disease.
A cataract is a painless cloudy lens in the eye that causes blurry vision. It progresses slowly as we age (most people who live long enough will have some cataract-like changes to their cornea). Other causes of cataracts include diabetes, trauma, some medications, and excessive UV light exposure.
Your doctor can see a cataract while doing a routine eye exam. Treatments for cataracts include eyeglasses, magnifying lenses, or surgery. Surgery is curative as the cloudy lens is removed and replaced with an artificial one. The need for surgery and the risks involved should be discussed with your eye doctor.
Age-Related Macular Degeneration (AMD)
Age-related macular degeneration is an eye disease with onset at any age, usually after age 60, that progressively destroys the macula, the central portion of the retina that helps with focus. It rarely causes total blindness as only the center of vision is affected.
There are two types of AMD: wet and dry. In wet AMD, abnormal blood vessels behind the retina start to grow, leaking blood and fluid, causing loss of central vision, which may occur quickly. In dry AMD, the light-sensitive cells in the macula slowly break down causing central vision to diminish over time.
Retinal Detachment
Retinal detachment occurs when the retina (tissue in the back of the eye) separates (detaches) from its underlying structures. The buildup of fluid behind the retina is what separates the retina from the back of the eye. Retina detachments are often painless, and symptoms that may be noticed include perception of flashing lights, floaters, or a curtain drawn over your visual field. Risk factors for retinal detachment include being a nearsighted adult age 25 to 50, or an elderly person after cataract surgery. Treatment for a detached retina involves surgery, mostly using lasers, that can improve vision affected by the retinal detachment.
Conjunctivitis (Pink Eye)
Conjunctivitis, or pinkeye, is redness and inflammation of the clear tissue covering the eye and the inside of the eyelids (conjunctiva). It is commonly caused by bacterial or viral infections but may also be due to irritants (chemicals, pollutants, or allergens).
Most cases of infectious conjunctivitis are viral and do not need treatment with antibiotics. Bacterial conjunctivitis can be treated with antibiotic drops or ointments prescribed by your doctor. A crusty discharge may make it difficult to open the eyelids. If this happens a warm, wet compress may be applied to the eyes to gently remove the crusting.
To reduce the spread of the infectious conjunctivitis, wash hands frequently, do not share
Uveitis is inflammation to the middle layers of the eye (the uvea). The uvea is the layer of the eye that contains the arteries and veins that feed the important structures used in vision. Causes of uveitis include trauma or injury to the eye, infections, or rheumatologic or inflammatory diseases that affect other parts of the body. The main symptom of uveitis is pain in the eyeball. The eye will look red (bloodshot) and you may notice blurred vision, light sensitivity, and spots in your vision.
Treatment for uveitis depends on the cause. Anti-inflammatory or antibiotic drops, along with pain medications may be prescribed.
Eye Allergies
Severe eye allergies may cause damage to the eye that may threaten eyesight. Allergies can cause chronic inflammation that may permanently damage the cornea. Causes of eye allergies are usually due to seasonal allergies, sensitivities to cosmetics or medications, or dust. Over-the-counter eye drops that contain antihistamines or decongestants are usually helpful. Consult a doctor if OTC remedies do not work, or if you experience pain, discharge, or extreme eye redness.
Sty (Stye)
A sty (also spelled stye) is an infection of the oil gland at the base of an eyelash. It appears as a red, raised pimple on the edge of the eyelid. Symptoms of a sty are pain, tenderness, redness, and swelling with a small pustule. The eyeball itself may feel irritated or as if something is scratching it due to the swelling of the eyelid. Treatment for a sty includes warm compresses applied to the affected area for 10 minutes, up to six times daily. If the sty comes to a head and releases pus, it should be cleaned gently with soap and water. This rupture usually leads to the sty going away. If the sty is very large, painful, or affects your vision, see your doctor.
The cornea is the clear surface covering the front of the eye. It is normally smooth and round, following the contour of the eyeball. Weakness in the structure of the cornea can lead to pressure in the eyeball, causing an conical-shaped abnormal bulge to the front of the eye in a condition called keratoconus. Changes in the shape of the cornea make it difficult for the eye to focus even with the help of glasses or contact lenses. Keratoconus can also cause complications during certain eye surgeries. Treatment includes rigid contact lenses or corneal transplantation.
Blepharitis is inflammation of the eyelids. The inflammation can be found on the outer (anterior) or inner (posterior) eyelid and symptoms include burning, itching, swelling, flaky skin at the base of the lashes, crusting of the eyelids, tearing, or blurred vision. Common causes of blepharitis are problems with oil glands at the base of the eyelids, infections, or other skin conditions. Treatment includes good eyelid hygiene, including frequent cleaning, light scrubbing, using a mixture of water and baby shampoo. Severe cases of blepharitis may require antibiotics or steroids.
How Your Vision Is Affected By Cataracts
Light enters the eye and passes through the lens. The lens of the eye focuses light onto the retina, which transmits visual signals through the optic nerve to the brain. Clouding of the lens due to cataracts results in blurring of the images you see. Other problems with the eyes can also cause blurry vision, but cataracts produce some characteristic symptoms.
Cataract Symptom: Blurry Vision
The most common symptom of cataracts is seeing blurry images at any distance. People may describe their vision as foggy, cloudy, or filmy. Cataracts get worse with time, and less light reaches the retina. It may be especially hard for people with cataracts to see and drive at night.
Glare, or sensitivity to light, is another symptom of cataracts. It can be difficult for a person with cataracts to see in bright sunlight. Indoor lights may begin to seem too bright, or they may appear to have halos around them. Glare from oncoming headlights can cause problems with driving at night.
Cataract Symptom: Double Vision
Diplopia, or double vision, when looking with one eye can be another symptom of cataracts. This is not the same as diplopia that arises from improper alignment of the eyes. The double vision seen with cataracts occurs even when you look through only one eye.
Color Changes
Cataracts also affect color vision. Some colors may appear faded, and things may acquire a yellowish or brownish tint. This may not be noticed at first, but with time, distinguishing between blues and purples can be difficult.
Second Sight
The phenomenon known as “second sight” is another characteristic of cataracts. In this situation, the cataract acts as a stronger lens, temporarily improving the ability to see things at a close distance. People who formerly needed reading glasses may no longer need them. However, as the cataract worsens over time, this temporary improvement in near vision disappears.
New Prescription
People with cataracts often need frequent changes in their eyeglasses or contact lenses because their vision deteriorates over time.
Who Can Get Cataracts?
Most cataracts occur in older people and are related to the aging process. Over half of Americans over 65 have cataracts. Sometimes, babies can be born with cataracts, known as congenital cataracts. Uncommonly, children can get cataracts as a result of illness or trauma to the eye.
What Are the Causes of Cataracts?
It is not precisely understood why people get cataracts. Aging is a known risk factor. Other factors that may also play a role in the development of cataracts include:
Excessive use of alcohol
Trauma to the eyes
Extended use of corticosteroids
Prolonged radiation or sun exposure
How Are Cataracts Diagnosed?
Cataracts can be diagnosed with an eye exam. The eye exam contains a vision test and an examination of your eyes using a slit lamp microscope. The pupils are dilated with special eyedrops to provide a better view of the back of the eye, where the retina and optic nerve are located.
Cataract Surgery
Surgery to remove cataracts may be required if the related vision loss cannot be corrected with glasses or contact lenses. Cataract surgery involves removing the cloudy natural lens and replacing it with an artificial lens. The operation is usually done on an outpatient basis and is very safe and effective. For those who need surgery on both eyes, the surgery is usually done on one eye at a time.
Types of Cataract Surgery
The most common type of cataract surgery is known as phacoemulsification (phaco). In this procedure, the doctor makes a tiny incision in the eye and breaks up the lens using ultrasound waves. The lens is then taken out and replaced with an intraocular lens (IOL). Another type of cataract surgery is called extracapsular cataract surgery. This procedure involves a larger incision and removal of the cloudy lens in one piece. In most cases, placement of an IOL eliminates the need for thick eyeglasses or contact lenses.
Innovations In Cataract Surgery
New developments in cataract surgery allow for procedures that correct both near and distance vision, reducing or even eliminating the need for glasses after the operation. Conventional “monofocal” lenses only correct distance vision, so people still need reading glasses after surgery. So-called “toric” implants are available to correct astigmatism. This picture illustrates a lens in development (shown next to a dime) that offers better color vision.
What to Expect After Cataract Surgery
After surgery, your eyes may itch and feel sensitive to light for a few days. You may need to wear a shield or glasses for protection, and you may be prescribed eyedrops to speed the healing process. It takes about 8 weeks for the eye to completely heal even though changes in vision are apparent shortly following the surgery. You may still need glasses for distance vision or reading, after the surgery, and it is likely that you will require a new prescription after your eye has healed.
Risks of Cataract Surgery
Cataract surgery does not commonly result in complications. When complications occur, they are usually related to infection, bleeding, or changes in eye pressure. All of these are treatable when recognized early. The risk of retinal detachment is slightly increased, and this complication requires emergency treatment. In some cases, lens tissue is left behind to support the IOL, and this tissue can become cloudy over time, forming an “after-cataract.” This can be permanently corrected with a laser treatment.
Should You Have Cataract Surgery?
It’s unusual for cataracts to require immediate removal, so you can take your time to decide about surgery. Cataracts affect vision slowly over time, so it’s possible to wait to have surgery until glasses no longer correct the vision problems. People who do not feel that cataracts are causing significant problems may opt to postpone or not undergo surgery.
Cataracts Prevention Tips
Remember, there are steps you can take to lower your risk of getting cataracts:
Don’t smoke.
Always wear a hat or sunglasses in the sun.
Keep diabetes well controlled.
Limit alcohol consumption.

About the author

Christian Voice