Most eye diseases can be prevented with regular eye exams and early treatment. We encourage you and your family to have an eye exam. The following contains a list of the most common eye conditions.
Common Eye Conditions:
Diabetes is the leading cause of blindness in adults under the age of 65. It is a complex disorder involving small blood vessels. These blood vessels provide nutrients to all the structures in the body, including the eyes. In diabetes, the blood vessels begin to leak fluid and blood. This causes damage to the surrounding structures and interferes with the transport of needed nutrients. Research findings show that complications can be delayed with proper care and monitoring of the disease.
Diabetes can affect many structures in the eye, causing double vision from the muscle palsies, fluctuations in vision from sugar level changes and decreased vision from cataracts. The most serious vision problems arise from hemorrhages in the retina, from swelling of the retina and from blood vessel growth under the retina. Laser therapy is used, when possible, to treat the retina.
Retinal disease in diabetes is divided into two forms: (1) Non-proliferative and (2) Proliferative. Non-proliferative retinopathy is present when there are hemmorrhages, small dilations of the vessel walls and leakage of fluid into the surrounding retina. Proliferative retinopathy has the added problem of new blood vessels forming. These vessels will leak and bleed if left untreated. The most common cause of decreased vision is swelling of the retina from leaky blood vessels. Lasers are used to treat these leaks when possible.
Regular examinations are critical for early diagnosis and to determine when treatment will be most effective. Vision can be preserved in the majority of patients who are diagnosed early and examined regularly.
Macular degeneration is the leading cause of vision loss after the age of 50. The disease occurs equally in men and women, and is more common among Caucasian people. There is some evidence that heredity plays a role. In macular degeneration, central vision is lost, but good peripheral vision may continue. While both eyes are affected, one eye may be ore affected than the other.
There are two types of macular degeneration: the nonexudative (dry) form and the exudative (wet) form. In the dry form, there is a slow loss of central vision. No treatment has proven to be effective. However, recent studies suggest that eating spinach and kale reduces the rate of deterioration. Many patients benefit from low vision aids, especially for reading. It is important to look daily for any changes in the size and shape of the area of vision loss. Such changes may signal onset of the wet form of macular degeneration, so they require immediate evaluation. To monitor for changes, patients are instructed in the use of an Amsler grid.
In the wet form of macular degeneration, there is a rapid deterioration of vision, often accompanied by distortion of straight lines, or by the appearance of a blind spot, at or near the center of the visual field. The sudden onset of vision loss is caused by hemorrhage or fluid leakage close to or into the area of central vision. Laser treatment may be advised and should be performed within 72 hours after the initial onset.
The lens inside the eye is normally almost transparent. Its function is to help focus light onto the retina, the back lining of the eye. The tern cataract refers to any loss of transparency. Cataracts occur in many forms and are due to a variety of causes. Most commonly, cataracts are associated with aging. They may also be caused by trauma, radiation, ultraviolet light, medications and systemic diseases (such as diabetes) and some cataracts are congenital. Not all cataracts are progressive, but those that are cause a gradual, painless loss of vision.
In the early stages of cataracts, frequent changes in prescription can often help preserve vision. Cataract surgery is indicated when the decrease in vision starts to interfere with the patient’s normal activities. Cataract removal, one of the most frequently performed surgeries in the United States, has very good results and low complication rates.
Presbyopia is a condition that generally presents itself in the early to mid forties. The onset of presbyopia is characterized by a decrease in the comfort and clarity of near vision. This decrease of clarity is brought about by a change in the eye’s ability to focus from distance to near. Reading glasses, bifocals, or progressive addition spectacle lenses easily compensate for the nearpoint blur. Contact lenses are also an alternative for the necessary nearpoint correction.
Hyperopia is more commonly referred to as “Farsightedness”. This terminology accurately describes this refractive error, in that objects in the distance are generally more clear than objects at near. Depending on the amount of hyperopia that exists, an individual patient may experience everything from no blur at distance or near, to blur at both distance and near. At lower levels hyperopia may be accommodated for by the focusing muscles in the eye. Higher levels of hyperopia left uncorrected may cause eyestrain, and headaches in addition to blurred vision.
Myopia is more commonly referred to as “Nearsightedness”. This terminology accurately describes this refractive error, in that objects at near are clear, and objects at a distance are blurred. Myopia tends to be somewhat progressive in nature. The bulk of myopic progression seems to occur in the growth and maturation phase of childhood and adolescence. Additionally, nearpoint work in significant amounts may also promote and increase myopic progression. The blurred vision that is associated with myopia is easily compensated for by glasses, contact lenses or refractive surgery.
Astigmatism is perhaps the most common visual anomaly that exists. Astigmatism in smaller amounts may not cause any blurred vision, discomfort, or headache. Larger amounts of astigmatism may cause any one or all of the previously mentioned symptoms to varying degrees. Astigmatism may cause blurred vision at distance and near in addition to complaints of glare and double vision.
Fluid is secreted into the eye to help nourish structures inside the eye. After circulating, the fluid drains out of the eye. When drainage from the eye is reduced, the pressure inside the eye increases. Increased pressure causes damage by interfering with the blood supply in the small blood vessels serving the optic nerve. When the blood supply to the nerve is decreases, degeneration of the nerve and loss of vision result. Increased pressure on the nerve also damages the delicate tissue through which the nerve fibers pass from the retina. This causes damage to the nerve fibers and loss of vision and is termed glaucoma.
Ocular hypertension describes a condition where the fluid pressure inside the eye is above normal but there is no clinically detectable loss of vision or damage to the optic nerve and retinal fibers, the changes which would indicate glaucoma and the need for treatment. Patients with ocular hypertension require no treatment, but frequent evaluation is critical to determine if damage is occurring.
Glaucoma – Primary Open Angle
Open angle glaucoma is a slowly progressive disease which causes decreased vision, ranging from only slight loss to absolute blindness. Both eyes are affected. There are no symptoms until loss of vision occurs, at which point the structures in the eye have already been substantially damaged.
Damage inside the eye occurs when there is an increase in the fluid pressure inside the eye. Normally, fluid is secreted into the eye to help nourish structures inside the eye. When drainage from the eye is reduced, pressure inside the eye increases. Increased pressure inside the eye causes damage by interfering with the blood supply in the small blood vessels serving the optic nerve. When the blood supply to the nerve is decreased, degeneration of the nerve and loss of vision result. Increased pressure on the nerve also damages the delicate tissue through which the nerve fibers pass from the retina. This causes damage to the nerve fibers and loss of vision.
People who have a family history of glaucoma, and those who are diabetic, nearsighted, or African-American have a higher risk of developing glaucoma.
Treatment is aimed at lowering the pressure inside the eye, in order to prevent further nerve damage. There are no set rules about when to begin therapy or which therapy to use. Eye drops are typically the first type of medication used. If they are not effective, oral medication or surgery is indicated. Using the medication as prescribed is extremely important in controlling the disease. If left untreated, glaucoma can lead to blindness.
Glaucoma – Acute Closed Angle
Angle closure glaucoma occurs when there is a sudden increase in fluid pressure inside the eye. Normally, fluid is secreted into the eye to help nourish structures inside the eye. When the drainage channel is blocked, fluid pressure increases, causing severe pain and loss of vision. Rainbow colored haloes are seen around lights, and the severe pain often causes nausea and vomiting. Patients who are pre-disposed to this condition generally have a narrow area through which the fluid drains, making it more easily blocked by the iris, the colored part of the eye.
Angle closure glaucoma requires immediate treatment. Every effort is made to reduce the fluid pressure in the eye, by using eye drops and oral medication. Laser surgery is used to make a small permanent hole in the iris, so that fluid can pass through to the drainage channel, even if it is again blocked by the iris. If this glaucoma is left untreated, permanent loss of vision occurs.