Most commonly, vision loss among older people is due to colluding of the lens of the eye (cataracts) or to damage of the optic nerve (as occurs in glaucoma) or the retina (as occurs in age related macular degeneration and diabetic retinopathy). A less common cause of vision loss is blockage of the blood supply to the eye. Eyelid disorders mostly change the appearance of the eye, but they can cause discomfort and contribute to vision loss as well.
Whatever the reason for vision loss, any vision change can compromise an older person’s quality of life and, indirectly, health. Loss or vision can be especially devastating to older people coping with other problems as well, such as poor balance and hearing loss. In such cases, vision loss can contribute to significant injury and can impair a person’s ability to perform daily activities.
Normal age-related vision loss is called presbyopia. Presbyopia is caused by hardening of the lens of the eye and usually begins age 40. Presbyopia isn’t a disease but rather a natural aging process, and diagnosed by a simple examination. Although presbyopia is a naturally occurring process rather than a disease, a number of diseases do cause vision changes that have different symptoms and treatments.
Cataract is a clouding of the lens of the eye. A cloud lens blocks light from entering the eye. Most cataracts grow slowly until they cloud the entire lens, causing progressive, painless vision loss. Cataracts are the most common cause of reversible vision loss among older people in the United States. The first symptom of a cataract is often blurred vision. Sometimes glare is the initial symptom. Colors may seem more yellow and less vibrant. The person may see rings of light around objects (double vision).
Cataracts usually require no treatment until vision is significantly impaired, Eyeglasses and contact lenses may improve a person’s vision, as may wearing sunglasses that block UV light. Avoiding lighting that shines directly in the eyes and using lighting that brightens without shining in the eyes. Beyond these measures, surgery is the only treatment that provides a cure. However surgery should be performed only when vision impairment is making the person feel unsafe, uncomfortable, or unable to perform daily tasks.
Glaucoma is a disorder that damages the optic nerve, leading to progressive, irreversible vision loss. Glaucoma is typically associated with high pressure within the eye, although it can occur with normal pressure. How the high pressure damages the cells of the optic nerve is unknown. Glaucoma is classified as open-angle (chronic) or closed angle (acute). Open-angle glaucoma is much more common than closed-angle glaucoma. In both kinds, people who have had glaucoma in one eye are likely to develop glaucoma in the other eye. Either kind can cause blindness if left untreated. Blindness often can be prevented, however, with the use of eye drops and surgery that decrease eye pressure.
Open-angle glaucoma is painless and causes no early symptoms. The most important symptom is the development of blind spots, or areas of vision loss, over months to years. The blind spot slowly grow larger and merge. The changes may progress to the point where only a small central island of vision remains, in which the person can see straight ahead but becomes blind in all other directions (tunnel vision). If glaucoma is left untreated, eventually even central vision can be lost.
Closed-angle glaucoma causes abrupt onset of severe pain in and around the eye, headache, redness, blurred vision, rainbow colored halos around light, and sudden vision loss. Close-angle glaucoma is considered a medical emergency, because if left untreated, blindness can occur quickly as 2 to 3 hours after the start of symptoms. The goal Vision 20 reviews of treatment is to prevent the onset of vision loss or to stop its progression. For Open-angle glaucoma; drops are the primary treatment. They either decrease production or increase drainage of fluid in the eye. An older person may find it difficult or impossible to administer eye drops because of arthritis or other impairments. Alternatively a Caregiver can administer the drops
Surgery or laser therapy is almost always needed if the person has closed-angle glaucoma. These treatment methods may also be needed for people with open-angle glaucoma if eye drops cannot effectively control eye pressure. There is no cure for open-angle glaucoma. Therefore, eye drops must be used for the rest of the person’s life. In addition, regular checkups are needed for monitoring eye pressure, optic nerve health, and areas of vision seen out of each eye.
Age- Related Muscular Degeneration: Deterioration of the macula, the central and most sensitive area of the retina, Macular degeneration is common cause of irreversible central vision loss among older people. Muscular degeneration is categorized into two types:
Dry (non-neovascular). The most common, the light-sensitive cells of the macula may be lost, and the retina thins (atrophies). Wet (neovascular). Abnormal blood vessels develop beneath the macula. These vessels leak fluid and blood, which result in the formation of scar tissue. Scar tissue can impair vision by causing light-sensitive cells to die. Only a few people with dry muscular degeneration eventually develop wet macular degeneration. However, once wet macular degeneration develops in one eye, there is a 50%chance that it will develop in the other eye within 5 years. People who smoke or who have high blood pressure may be at higher risk of progression to wet type. Most people with dry type have no symptoms, although some people experience mild distortion in their vision. People with the wet type often experience an abrupt deterioration and distortion of vision over days or weeks.
People who experience distortion in their central vision or the gradual appearance of a blind spot on one eye, from any type degeneration, have difficulty reading, driving, seeing faces, and watching television. People retain their peripheral vision, which allows them to perform daily tasks (other than driving and reading) and remain independent. Total blindness is rare, but if both eyes are affected, blindness may result.