The term “low vision” is used to describe someone’s sight that cannot be corrected by glasses, contacts, or surgery. Causes of low vision can include age-related macular degeneration, glaucoma, diabetes, and other medical conditions.
What is low vision?
Low vision is a category of vision loss that includes poor eyesight, poor night vision, and blurry sight. It’s not blindness, but it can still be tough to see. Low vision is usually caused by age-related macular degeneration, glaucoma, or diabetes. Tools can make low vision easier for people who have it.
Low vision, or impaired vision, can be defined as a number of different problems. The American Optometric Association defines low vision as two groups:
Partially sighted
If you have vision that ranges from 20/70 to 20/200, you might need a different kind of prescription.
Legally blind
the person cannot see better than 20/200 with correction and has a field of vision less than 20 degrees wide.
Low vision causes
There are many causes of low vision, but the most common are as follows.
Macular degeneration
Macular degeneration is a disorder which affects the retina at the back of the eye. This can lead to blurry vision and, in some cases, blindness in central vision. Some common symptoms of macular degeneration are difficulty reading, an inability to recognize faces, and distorted colors.
The most common form of age-related macular degeneration is the dry form, which progresses slowly and gradually. The wet form of the disease, however, progresses more rapidly and severely. This is due to abnormal blood vessels that develop under the macula and leak fluid and blood.
Age-related macular degeneration is a terrible condition that can lead to blindness. Macular degeneration is not just exudative, but also non-exudative. Recent studies estimate that over 1.6 million people – mainly over the age of 50 – have macular degeneration.
Cataracts
Cataracts are a clouding of the lens inside the eye. They often occur in people who are older, and one of the most common causes is long-term exposure to sunlight or high-energy radiation. They can also be caused by injury, disease, or inherited disorders like diabetes. Cataract surgery usually involves removing the lens or replacing it with an intraocular lens implant that restores vision. Sometimes, cataract surgery is not possible in people who have other eye diseases.
Glaucoma
Glaucoma is a common eye disease that affects the optic nerve, causing defects in peripheral vision and difficulties with night vision. The most common form of glaucoma is caused by increased pressure in the eye, but it can also happen when pressure does not increase, but there is not enough blood flow to the optic nerve. In this case, there are no early symptoms, but when first detected, it is treated with drugs or surgery.
Diabetic retinopathy
People with diabetes might experience changes in their vision and visual functioning on a daily basis. There are two types of diabetic retinopathy: nonproliferative diabetic retinopathy (NPDR) and proliferative diabetic retinopathy (PDR). The condition causes blood vessels that nourish the retina to develop abnormal branches that leak. This can cause vision loss over time and may severely damage the retina.
Retinitis pigmentosa
Retinitis pigmentosa is an inherited disease that causes your night vision to gradually get worse. It destroys side vision and may result in total vision impairment. It’s characterized by night blindness-the first symptom, which usually begins to occur during adolescence-and over time, it reduces the amount of light you’re able to see.
Low vision care
Low vision specialists who specialize in low-vision rehabilitation examine and rehabilitate patients with visual impairments. They help those with different types of problems, including cataracts, glaucoma, macular degeneration, and retinal detachment. After conducting a thorough examination, which includes tests to determine the patient’s problem, the doctor will prescribe a treatment plan specific to their needs.
Vision rehabilitation maximizes the patient’s abilities to see, so they can achieve their visual goals and improve the quality of their life. A patient’s individual rehabilitation plan may include prescription glasses or contact lenses, optical and electronic magnification devices, assistive technology, glare control with therapeutic filters, contrast enhancement, eccentric viewing, visual field enhancement, non-optical options and referral for additional services with other professionals.
