Low vision is a state of severe vision impairment. Technically, if visual acuity is recorded at 20/200 or less in the better eye, a person is termed to have low vision [1]. The number here means that a person with low vision can see at 20 feet what a regular person can see at 200 feet. Similarly, if the visual ‘field’ (the full extent of what we can see) is restricted to 20 degrees (assuming about 180 degrees of vision) that too can be classified as low vision.

Unlike complete blindness, people with low vision can have some level of vision, but the impaired sight can make it difficult to perform everyday tasks (like reading, recognizing faces or navigating their environment) unaided. 

Vision impairment can stem from a range of diverse eye diseases, conditions and disorders like:

• Inherited diseases: There are hundreds of rare, inherited eye diseases (like retinitis pigmentosa) that can result in low vision. As these conditions are not fully understood, treatment options remain under-developed. Most conditions may have no treatment too, just mitigation strategies. 
• Age-related Macular Degeneration: AMD or macular degeneration is a major cause of low vision in older adults where the retina, or back part of the eye, begins to weaken and compromise central vision (seeing things directly in the front).
• Diabetic retinopathy: DR is a condition in people with diabetes where unregulated blood sugar levels harm the blood vessels in the retina, causing vision loss.
• Glaucoma: This is a group of eye conditions that damage the optic nerve connecting the eye to the brain, mostly due to buildup of fluid. It is a lifelong condition with no true ‘cure’ in sight.

Low vision can present itself in different forms for different people. It may affect:

• Central vision: Difficulty seeing things directly in front of the eye.
• Peripheral vision: Makes it harder to see things in the external range.
• Night vision: Affecting ability to see in low light or in the dark.
• Visual acuity: Blurriness or haziness affecting vision even in well-lit environments.

Low vision is permanent in most cases. However, medication, surgeries or corrective eyewear may sometimes improve vision or prevent it from becoming worse.

The options for treatment will depend on the underlying cause that led to low vision. Make sure to ask your eye doctor for any potential treatments for support your existing vision or stop it from worsening. For many, vision rehabilitation can be a source of support and therapy. 

The goal of rehabilitation is to optimize your vision, that is to help you live independently to the best extent possible with the current sight. This includes a variety of resources.

Low vision aids:

• Optical telescopes and magnifiers
• Prescription lenses or glasses
• Products with large print and high contrast
• White canes 
• Smart speakers
• Accessible mobile apps
• E-reader and magnifier extensions for computers

Practical training:

• Using environmental cues like sound, smell and touch to create a mental map of everyday areas.
• Arranging living areas to make them more accessible and to prevent falls.
• Ensuring safe movement in settings like public transport, workplace, and streets.