Low vision is a level of vision impairment that makes everyday activities difficult even after ordinary glasses, contact lenses, medication, or surgery have provided as much correction as they reasonably can. It is not a single disease. The underlying eye or neurologic condition determines whether the vision loss is stable, treatable, or progressive.
Low vision can make reading, recognizing faces, driving, using a computer, navigating unfamiliar places, or performing detailed tasks more difficult. Vision rehabilitation and assistive tools can help people use their remaining vision more effectively.
What Causes Low Vision?
Common causes include:
- age-related macular degeneration
- glaucoma
- diabetic retinopathy
- advanced cataract or vision loss that remains after treatment
- retinal or optic-nerve disease
- eye or brain injury
- certain inherited eye conditions
Low vision becomes more common with age because many of the diseases that cause it are more common in older adults. Aging itself does not automatically cause low vision.
Is Low Vision the Same as Legal Blindness?
No. “Low vision” is a functional description and covers a wide range of visual impairment. “Legal blindness” is a specific eligibility definition used in the United States and can be based on best-corrected central visual acuity or a severely restricted visual field.
That means a single eyeglass prescription number or one acuity number does not tell the entire story about how well a person functions visually.
What Types of Vision Can Be Affected?
Low vision can affect different parts of visual function, including:
- central vision — making reading or recognizing faces difficult
- peripheral vision — making navigation and hazard detection harder
- night vision — making low-light environments difficult
- contrast sensitivity — making low-contrast objects, steps, or print harder to see
- overall clarity — causing blur or haze even with the best available correction
How Is Low Vision Evaluated?
An eye examination looks for the cause of the vision loss and determines whether any treatable eye condition is contributing. The doctor may assess visual acuity, visual field, contrast, eye health, and how the vision problem affects daily activities.
A person who has not yet received all appropriate treatment for the underlying eye disease may not truly be at the “rehabilitation only” stage. For example, cataract, diabetic macular edema, or some forms of wet macular degeneration may have treatment options that improve or preserve vision.
Can Low Vision Be Cured?
It depends on the cause. By definition, low vision refers to impairment that remains despite standard correction or treatment, so the lost vision often cannot be fully restored. But treatment of the underlying disease may still be important to protect the remaining vision or, in some conditions, improve it.
The next goal is to help the person function as independently and comfortably as possible with the vision they have.
What Is Vision Rehabilitation?
Vision rehabilitation is a set of services and strategies designed to help people make the most of their remaining sight. It may involve a low-vision optometrist or ophthalmologist, occupational therapists, orientation-and-mobility specialists, and other rehabilitation professionals.
Depending on the person's needs, rehabilitation may include:
- handheld, stand, electronic, or spectacle magnification
- high-contrast or improved task lighting
- large-print material
- screen magnification and text-to-speech tools
- phone and computer accessibility settings
- strategies for safer navigation, cooking, medication management, and other daily tasks
Does Park Slope Eye Provide Low-Vision Rehabilitation?
No. We can examine your eyes, update your prescription, check for treatable eye disease and refer you to a low-vision specialist or rehabilitation service.
Park Slope Eye can evaluate eye health, update the best available prescription, identify or monitor medical eye disease within the practice's scope, and help determine when referral to an ophthalmologist, retina specialist, low-vision specialist, or vision-rehabilitation service is appropriate.
When Should You Seek an Eye Evaluation?
Gradual difficulty with reading, faces, contrast, or mobility deserves an eye examination to determine the cause. Sudden vision loss, a new missing area of vision, a curtain or shadow, new flashes and floaters, severe eye pain, or new neurologic symptoms require more urgent evaluation.
Call 911 if vision loss or double vision comes on suddenly with weakness, numbness, facial droop, confusion or trouble speaking; these can be signs of a stroke.
Something urgent? Don’t wait for an online appointment: see our urgent and emergency guidance.
If your vision has changed, book an appointment for an eye examination so the cause and next steps can be clarified.
Originally published . Substantially updated .