Some people cannot see well.
They might see a little. Or they might not see at all. This can make walking hard. Tools can help them.
Doctors can help too. Do you use your eyes to see?
{
"text": "Some people cannot see well.
This is called vision loss. They might see a little. They might not see at all.
\n\nVision loss can make daily tasks hard. It can be hard to read. It can be hard to walk. \n\nMany things cause this. Some people have cloudy eyes. Others have eye sickness.
\n\nDoctors can help people see better. They use tools like glasses. Some people use tools to feel things. \n\nMost vision loss can be fixed. Doctors can treat many eye problems. This helps people live well.",
"media
Some people cannot see clearly. This is called visual impairment. It means a person has trouble seeing. This can be a little or a lot.
Some people have low vision. This means they can still see a bit. Others are blind. This means they cannot see at all.
Many things cause vision loss. One big cause is refractive errors. These are problems with how the eye focuses light. This includes being near-sighted or far-sighted. Another cause is cataracts. Cataracts make the eye cloudy. They are the most common cause of blindness.
Vision loss can make tasks hard. It might be tough to walk or read. People can use tools to help. They might use glasses or contact lenses. Some use tools like braille. Braille is a way to read with touch.
Doctors can help many people. The World Health Organization says 80% of vision loss can be fixed. This includes treating infections or cataracts. This helps people live better lives.
Visual impairment is when a person cannot see clearly. It can mean seeing things with a bit of blur. It can also mean having no sight at all. This is often called blindness.
These vision problems can make daily tasks very hard. Tasks like reading or walking might become difficult. People may need special tools to help them every day. These tools can include glasses or even assistive devices.
Vision loss happens in many different ways. One common way is through uncorrected refractive errors. This happens when the eye does not focus light correctly. These errors include being near-sighted or far-sighted. Another common cause is cataracts, which make the eye cloudy.
Cataracts are actually the most common cause of blindness. Other causes include glaucoma or infections like river blindness. Sometimes, problems in the brain can also cause vision issues.
Doctors use eye exams to find these problems. They look at how well a person sees at different distances. In 2010, the World Health Organization changed how they define vision loss. They now look at "presenting visual acuity." This means they look at how a person sees right now. This is better than looking at how they see with glasses.
This change helps include more people who lack medical care.
There are many important facts about vision around the world. The World Health Organization says 80% of vision loss is preventable. This includes treating things like cataracts or certain infections. There were 940 million people with some vision loss. Out of these, 246 million had low vision. About 39 million people were blind.
Most people with poor vision are over 50 years old. They often live in the developing world.
Many tools help people with vision loss live well. Some people use braille to read with their fingers.
Others use a long cane to help them walk.
Some people even use guide dogs to help them move.
Low vision specialists can also help people use magnification. This might be a telescope for seeing far away. It might be electronic tools for reading close up. These tools help people stay active and connected to others.
Visual impairment, often called VI or VIP, is the partial or total loss of visual perception. This condition can range from mild blurriness to complete blindness. Without medical treatment or assistive tools, it can make daily tasks very difficult. Common challenges include reading text or walking safely through environments.
There are many different ways vision can be lost. One major cause is uncorrected refractive errors, which account for 43% of global cases. These errors include near-sightedness, far-sightedness, presbyopia, and astigmatism. Cataracts are another huge factor, causing 33% of cases and serving as the leading cause of blindness. Glaucoma accounts for 2% of visual impairment.
Other medical conditions also impact how we see. Age-related macular degeneration and diabetic retinopathy are significant causes. Some people experience vision loss due to corneal clouding or various infections. In some cases, the problem is not in the eye itself, but in the brain. This is known as cortical visual impairment. It can be caused by trauma, a stroke, or a premature birth.
Scientists and doctors use specific categories to classify vision loss. The World Health Organization (WHO) updated its definitions in 2010. They moved from using "best corrected visual acuity" to "presenting visual acuity." This means they measure how a person sees in their current state. This change helps identify people who lack access to glasses or surgery.
Distance vision is measured in specific categories. Category 0 involves no or mild impairment. Category 1 is moderate impairment, where vision is worse than 6/18. Category 2 is severe impairment, falling between 6/60 and 3/60. Categories 3, 4, and 5 represent different levels of blindness. These range from having some light perception to having no light perception at all. Near vision is also measured, specifically looking at acuity at a distance of 40 cm.
Different countries have their own legal definitions. In the United States, a person is legally blind if their vision cannot be corrected better than 20/200 in their better eye. They might also have a visual field of 20 degrees or less. The United Kingdom uses the Certificate of Vision Impairment to certify individuals. In the UK, being severely sight-impaired means one is unable to perform work where eyesight is essential.
Visual impairment has a massive global impact. There are approximately 940 million people living with some degree of vision loss. Of these, 246 million have low vision and 39 million are blind. Most people with vision loss are over the age of 50. They are also more likely to live in the developing world. However, the WHO estimates that 80% of these cases are preventable or curable.
Many people use specialized tools to navigate the world. Low vision specialists use magnification to help patients. This includes telescopes for distance and electronic tools for near tasks. Some people use a long cane to feel their way forward.
Others use guide dogs for mobility.
For reading, many people use braille, which is a system of raised dots.
Even everyday objects like banknotes have tactile features to help.
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