Different types of blindness: What blindness really looks like

06.08.197816.11.2021 by alexxlab

Содержание

What blindness really looks like

When most sighted people think “blindness,” they think of a world in total blackness. But, this is far from accurate. A variety of eye diseases, genetic disorders, and birth defects, as well as aging or suffering an injury, can interfere with healthy vision. And these visual impairments don’t all “look” the same.

For example, here is what 4 different types of blindness might look like:

People who experience total darkness all the time have “total blindness” whereas those who may be able to see some light, colors, and/or shapes are commonly referred to as having “low vision.” You might have a blind or blurry spot in the middle of your field of vision. Or your peripheral vision may be impaired. Or maybe, your visual impairment may be one, or a unique combination, of a myriad of other possibilities. Therefore, blindness is a spectrum of visual impairments affecting millions of children and adults worldwide.

CVI: The leading cause of blindness in children

Cortical/cerebral visual impairment (CVI) is the leading cause of blindness in children today.

What many kids with CVI see (No two kids are exactly the same):

What most people see:

Often, people associate blindness with ocular — or eye — impairment. However, CVI is neurological. For kids with CVI, the eye’s connection to and in the brain doesn’t work correctly. There isn’t a cure for CVI, but a child’s ability to use his or her vision may improve with the right assessment and educational programming.

This is why Perkins is hard at work designing new ways to teach kids who have CVI. And, we’re dedicated to supporting their parents, educating teachers, and collaborating with experts to reach more kids with CVI where they are today.

To help us reach these families and to help them reach each other, we created CVI Now, a website and Facebook Group to help families understand CVI, learn how to help their children every day, and find other families who share their experience.

What learning with CVI looks like

This is one way we teach kids with the leading cause of blindness, by controlling light and contrast using specialized equipment.

The right tools and techniques make it possible for our teachers to help kids retrain their brain to understand what their eyes see.

If caught early, kids with CVI can often improve the use of their vision through controlled environments, use of color and contrast and the dedicated attention of a teacher trained to address this kind of visual impairment.

Blindness and vision impairment

Definitions

The International Classification of Diseases 11 (2018) classifies vision impairment into two groups, distance and near presenting vision impairment.

Distance vision impairment:

Mild –visual acuity worse than 6/12 to 6/18
Moderate –visual acuity worse than 6/18 to 6/60
Severe –visual acuity worse than 6/60 to 3/60
Blindness –visual acuity worse than 3/60

Near vision impairment:

Near visual acuity worse than N6 or M. 08 at 40cm.

A person’s experience of vision impairment varies depending upon many different factors. This includes for example, the availability of prevention and treatment interventions, access to vision rehabilitation (including assistive products such as
glasses or white canes), and whether the person experiences problems with inaccessible buildings, transport and information.

Prevalence

Globally, at least 2.2 billion people have a near or distance vision impairment. In at least 1 billion – or almost half – of these cases, vision impairment could have been prevented or has yet to be addressed.

This 1 billion people includes those with moderate or severe distance vision impairment or blindness due to unaddressed refractive error (88.4 million), cataract (94 million), glaucoma (7.7 million), corneal opacities (4.2 million), diabetic retinopathy
(3.9 million), and trachoma (2 million), as well as near vision impairment caused by unaddressed presbyopia (826 million) (1).

In terms of regional differences, the prevalence of distance vision impairment in low- and middle-income regions is estimated to be four times higher than in high-income regions (1). With regards to near vision, rates of unaddressed near vision impairment
are estimated to be greater than 80% in western, eastern and central sub-Saharan Africa, while comparative rates in high-income regions of North America, Australasia, Western Europe, and of Asia-Pacific are reported to be lower than 10% (2).

Population growth and ageing are expected to increase the risk that more people acquire vision impairment.

Causes

Globally, the leading causes of vision impairment are:

uncorrected refractive errors
cataract
age-related macular degeneration
glaucoma
diabetic retinopathy
corneal opacity
trachoma

There is substantial variation in the causes between and within countries according to the availability of eye care services, their affordability, and the eye care literacy of the population. For example, the proportion of vision impairment attributable
to cataract is higher in low- and middle-income countries than high-income countries. In high income countries, diseases such as glaucoma and age-related macular degeneration are more common.

Among children, the causes of vision impairment vary considerably across countries. For example, in low-income countries congenital cataract is a leading cause, whereas in middle-income countries it is more likely to be retinopathy of prematurity. As
in adult populations, uncorrected refractive error remains a leading cause of vision impairment in all countries amongst children.

Impact of vision impairment

Personal impact

Young children with early onset severe vision impairment can experience delayed motor, language, emotional, social and cognitive development, with lifelong consequences. School-age children with vision impairment can also experience lower levels of educational
achievement.

Vision impairment severely impacts quality of life among adult populations. Adults with vision impairment often have lower rates of workforce participation and productivity and higher rates of depression and anxiety. In the case of older adults, vision
impairment can contribute to social isolation, difficulty walking, a higher risk of falls and fractures, and a greater likelihood of early entry into nursing or care homes.

Economic impact

Vision impairment poses an enormous global financial burden. For example, the annual global costs of productivity losses associated with vision impairment from uncorrected myopia and presbyopia alone were estimated to be US$ 244 billion and US$ 25.4
billion, respectively.

Strategies to address eye conditions to avoid vision impairment

While a large number of eye diseases can be prevented (e.g. infections, trauma, unsafe traditional medicines, perinatal diseases, nutrition-related diseases, unsafe use or self-administration of topical treatment), this is not possible for all.

Each eye condition requires a different, timely response. There are effective interventions covering promotion, prevention, treatment and rehabilitation which address the needs associated with eye conditions and vision impairment; some are among the most
cost-effective and feasible of all health care interventions to implement. For example, uncorrected refractive error can be corrected with spectacles or surgery while cataract surgery can restore vision.

Treatment is also available for many eye conditions that do not typically cause vision impairment, such as dry eye, conjunctivitis and blepharitis, but generate discomfort and pain. Treatment of these conditions is directed at alleviating the symptoms
and preventing the evolution towards more severe diseases.

Vision rehabilitation is very effective in improving functioning for people with an irreversible vision impairment that can be caused by eye conditions such as diabetic retinopathy, glaucoma, consequences of trauma and age-related macular degeneration.

WHO response

WHO’s work is guided by the recommendations of the WHO World report on vision (2019) and the resolution on “integrated, people-centred eye care, including preventable blindness and vision impairment” that
was adopted at 73rd World Health Assembly in 2020. The key proposal of the report and resolution is to make integrated people-centred eye care (IPEC) the care model of choice and to ensure its widespread implementation. It is expected that by shaping
the global agenda on vision, the report and resolution will assist Member States and their partners in their efforts to reduce the burden of eye conditions and vision impairment and achieve the Sustainable Development Goals (SDGs), particularly SDG
target 3.8 on universal health coverage.

Some of WHO’s key areas of work and activities in the prevention of blindness include:

Working with Member States and other partners in the field to provide recommendations on feasible global targets for 2030 on integrated people-centred eye care;
Observing and promoting World Sight Day as an annual advocacy event;
The ongoing development of technical tools to support the implementation of the recommendations of the World report on vision:
Guide for action for integrated people-centred eye care (IPEC)
Package of evidence-based eye care interventions to facilitate the integration of eye care interventions into health systems
Mobile health toolkit for myopia to increase awareness and health literacy of modifiable risk factors, potential irreversible consequences of myopia and the importance of spectacle compliance and regular eye examinations
The development and implementation tools to support countries to assess the provision of eye care services:
Eye care services assessment tool
Tool for Assessment of Diabetes and Diabetic Retinopathy Services
Tool for the Assessment of Glaucoma Services
Tool for the Assessment of Refractive Services
Tool for the Assessment of Rehabilitation Services and Systems

References

1) Vision Loss Expert Group of the Global Burden of Disease Study. Causes of blindness and vision impairment in 2020 and trends over 30 years: evaluating the prevalence of avoidable blindness in relation to “VISION 2020: the Right to Sight”.
Lancet Global Health 2020. doi.org/10.1016/S2214-109X(20)30489-7

2) Vision Loss Expert Group of the Global Burden of Disease Study. Trends in prevalence of blindness and distance and near vision impairment over 30 years: an analysis for the Global Burden of Disease Study. Lancet Global Health 2020. doi: 10.1016/S2214-109X(20)30425-3

3) Fricke, TR, Tahhan N, Resnikoff S, Papas E, Burnett A, Suit MH, Naduvilath T, Naidoo K, Global Prevalence of Presbyopia and Vision Impairment from Uncorrected Presbyopia: Systematic Review, Meta-analysis, and Modelling, Ophthalmology. 2018 May 9

Types of Blindness | Low vision

Humans are social animals and we live in a society where an individual’s identity is dependent on the people’s perception of them to an extent. So, we adapt to and live our lives based on direct and indirect feedback received from our family, friends and community. However, when it comes to people who are blind or have low vision, it is important to be sensitive towards such patients while giving feedback. There are unfortunately a lot of misconceptions around visual impaired individuals.

For instance, a child with macular dystrophy has blurry vision or distorted vision and can often progress to vision loss. Children with such eye disease can hardly read anything written on the blackboard. Further, these patients have normal appearing eyes, which is unlike the blindisms i.e. characteristic and repetitive behaviour of blind people. Visually impaired individuals rely on auditory cues (receiving signs through listening) more.

The visually impaired people are not as homogenous as the society may perceive it. The whole spectrum of impairment limits different aspect of vision. Let us understand these terms.

World Health Organization (WHO) has defined vision impairment as the condition including the range from partial sight to blindness.

A person is considered blind when the best corrected vision in the better eye is less than or equal to 6/60 and corresponding visual field is less than 20 degrees or worse from fixation point.

A Low Vision is defined as Visual acuity that is between 6/18 and 6/60 in the better eye after the best possible correction or corresponding visual field of more than 20 degrees and upto 40 degree from fixation point.

BLINDNESS

Complete Blindness is referred to as total loss of vision. There are many diseases that can cause complete blindness. These may be present either by birth or may develop later in life. India is becoming hub of diabetic patients, which causes diabetic retinopathy resulting in retinal damage. Thus, diabetes is also now a leading cause of blindness besides cataract and glaucoma.

NIGHT BLINDNESS

Night blindness is also known as Nyctalopia, which is, derived from Greek word that literally means inability to see at night. This type of vision impairment can also be present under dim light conditions. People with night blindness may have impaired vision but do not have total blindness. People with night blindness often have difficulty driving at night or seeing stars.

The most common and popular cause of Night blindness is a retinal disorder called retinitis pigmentosa. This is due to defect in those retinal cells that allow us to see properly in poor light. Besides this, there are also other factors that causes Nyctalopia that includes Vitamin A deficiency, glaucoma, glaucoma medicines, diabetes, cataracts, birth defects etc.

COLOR BLINDNESS

People with color blindness have inability to differentiate few colors. This is due to a defect in one of gene in X chromosome, hence more than females, males are affected with this type of visual impairment. Further, defect in retinal cells or optic nerve can also induce some form of color blindness is inherited one. Currently there is no treatment for the same, however, to enhance brightness between colors, certain contact lenses can be used. It is better to consult an eye doctor or eye care professional before reaching any decision.

Often vision impairment starts with many other signs and symptoms which if detected and treated at the right time may prevent blindness.

Some of the common signs and symptoms that should not be ignored are

Cloudy/Hazy/Blurry vision
Eye pain
Eye injury
Red eyes
Constant uneasiness in the eyes
Discomfort due to Contact Lenses use
Flashing Lights, Floaters in Your Vision
Sudden transient Vision Loss

Types of Visual Impairment

This section includes information on some of the main causes of visual impairment today. It describes symptoms, causes, and treatments, provides information on prevalence, and suggests devices that can help people with these conditions maintain their independence.

Albinism. Albinism is a pigment deficiency causing several physical conditions, including vision problems. People with albinism often have low vision, including severe light and glare sensitivity. Albinism occurs in one person in 17,000 in the United States. Read more about albinism

Cataracts. Cataracts are the leading cause of preventable blindness worldwide. They are responsible for over 50% of the world’s blindness, over 20 million people. Cataracts are a clouding of the lens of the eye that causes light to be diffused as it enters the eye, impacting the clarity of the visual image. Most cataracts are a natural result of aging, but they can also be due to trauma to the eye. Read more about cataracts

Diabetic Retinopathy. Diabetic retinopathy is a complication of diabetes in which retinal blood vessels leak into the retina, causing macular edema (swelling). It is often caused by elevated blood sugar levels. Diabetic retinopathy causes over 8,000 cases of new blindness annually and is the primary cause of blindness for adults in the U. S. Read more about diabetic retinopathy

Glaucoma. Glaucoma is the most common eye disease, affecting more than 80 million people worldwide. Glaucoma involves damage to the optic nerve, usually caused by fluid build-up and increased pressure inside the eye. The result is a loss of peripheral vision, and often difficulty seeing in dim lighting. Read more about glaucoma

Age-related Macular Degeneration (AMD). Age-related Macular Degeneration (AMD) is the foremost cause of vision loss among Americans who are 60 and older. AMD involves damage to the macula in the back of the eye resulting in loss of central vision. Since central vision is used for many tasks, including reading, this can result in a loss of independence. Read more about AMD

Retinitis Pigmentosa (RP). Retinitis pigmentosa is an inherited eye disease found in over 100,000 people in the United States. It causes retinal degeneration and severe visual loss. It is a progressive disease that begins in childhood or adolescence, resulting in a loss of part of the visual field, along with reduced night vision. It often leads to severe visual impairment and sometimes total blindness. Read more about retinitis pigmentosa

Stargardt Disease. Stargardt disease is the most common form of inherited juvenile macular degeneration, occurring in one in every 8,000 to 10,000 people worldwide. It causes gradual loss of central vision. It usually develops during childhood or adolescence, resulting in a loss of the central part of the visual field. Read more about Stargardt disease

Albinism

Albinism is a relatively rare congenital disorder that occurs in about one person in every 17,000 in the United States. It is characterized by a lack of pigment in the hair, skin, and eyes. It is associated with vision problems, including low vision, nystagmus, and photophobia.

What is albinism? Albinism is a pigment deficiency that causes several physical conditions, the most prominent being lack of color in the hair, skin, and eyes. Albinism is genetic and occurs in all races, in fact, in all vertebrates. People with albinism often have low vision, including photophobia, a sensitivity to light and glare. They also often have nystagmus, a rapid irregular movement of the eyes from side to side.

What can be done if albinism is diagnosed? People who are born with albinism are advised to avoid sunlight, not only because they can get sunburn more easily, but also because their condition puts them at greater risk for certain types of skin cancer. Their visual impairment means they frequently need assistive technology to read and work.

What devices can help? Many people with albinism find that video magnifiers enable them to enjoy the activities of work, school, and their personal lives. By adjusting the contrast on the video magnifiers, they can use a magnified view without discomfort or fatigue. Freedom Scientific’s video magnifiers all have easy contrast adjustments.

TOPAZ Desktop Video Magnifiers allow you to read magazines and letters, view family photos, write checks, or engage in your favorite hobby, all in the comfort of your home or office.

RUBY Handheld Video Magnifiers can slip comfortably into a pocket or purse, giving you easy access to photos, letters, menus, prescription labels, and so much more, wherever you go.

ONYX Portable Video Magnifiers move from school to home to the office to help you see the board, read your assignments, take notes, do crafts, or to read, write, and view business presentations.

SAPPHIRE Handheld Video Magnifier magnifies bills, bank statements, and even three-dimensional items like food labels and pill bottles for continued independence.

MAGic Screen Magnification Software provides screen magnification and screen reading for low vision computer users.

Cataracts

Cataracts are the leading cause of preventable blindness worldwide. They are responsible for over 50% of the world’s blindness, over 20 million people. Cataracts are a clouding of the lens of the eye that causes light to be diffused as it enters the eye, impacting the clarity of the visual image. Most cataracts are a natural result of aging, but they can also be due to trauma to the eye.

What is a cataract? A cataract is a clouding of the lens of the eye. This causes light to be diffused as it enters the eye, impacting the clarity of the visual image. Cataracts usually develop quite slowly, so that people do not notice them until their vision is impacted. Common symptoms of cataracts are blurred vision, glare or light sensitivity, double vision, fading or yellowing of colors, poor night vision, and a need for increased light to read or perform close tasks.

While the most common cataracts are age-related, there are other types of cataracts that can result from diseases such as glaucoma, diabetes, or eye injury. Risk factors for cataracts include prolonged use of corticosteroids, excessive consumption of alcohol, smoking, and excessive exposure to sunlight. Usually cataracts develop in both eyes, but one may be worse than the other. Studies show an increased chance of cataract formation with unprotected exposure to ultraviolet (UV) radiation. For this reason, doctors recommend using sunglasses that block UV radiation while outside, even on cloudy days.

What can be done if cataracts are diagnosed? The main treatment for a cataract is surgery to replace the damaged lens. This surgery can usually be performed on an out-patient basis. Approximately one-half million people each year in the United States have cataract surgery, most of them over age 65.

What devices can help? Most cataracts are treatable with cataract surgery. If cataract surgery is not an option, it is important to be able to magnify text and objects so they are large enough to be visible outside the clouded central vision area. Freedom Scientific’s line of video magnifiers and screen magnification software can help with this.

TOPAZ Desktop Video Magnifiers allow you to read magazines and letters, view family photos, write checks, or engage in your favorite hobby, all in the comfort of your home or office.

RUBY Handheld Video Magnifiers can slip comfortably into a pocket or purse, giving you easy access to photos, letters, menus, prescription labels, and so much more, wherever you go.

ONYX Portable Video Magnifiers move from school to home to the office to help you see the board, read your assignments, take notes, do crafts, or to read, write, and view business presentations.

SAPPHIRE Handheld Video Magnifier magnifies bills, bank statements, and even three-dimensional items like food labels and pill bottles for continued independence.

MAGic Screen Magnification Software provides screen magnification and screen reading for low vision computer users.

Diabetic Retinopathy

Diabetic Retinopathy is a complication of diabetes in which retinal blood vessels leak into the retina, causing macular edema (swelling). It is often caused by elevated blood sugar levels. Diabetic retinopathy causes over 8,000 cases of new blindness annually and is the primary cause of blindness for adults in the U.S.

What is diabetic retinopathy? Diabetic retinopathy is a condition that affects people with diabetes, in which elevated blood sugar levels cause damage to the blood vessels in the back of the eye. Without the proper nutrients supplied by the blood, the retina cannot stay healthy. When blood vessels leak or break, it distorts the vision. Scarring can develop, and in some cases, a detached retina can occur. These all lead to worsening vision and sometimes blindness.

Anyone with type 1 or type 2 diabetes can develop diabetic retinopathy, although those with uncontrolled blood sugar levels are at higher risk. Symptoms of diabetic retinopathy often begin with blurring of the vision that generally worsens over time. As it develops, people can experience cloudy vision, loss of color vision, shadows or blind spots, or floaters. People with diabetic retinopathy often have trouble seeing at night. Careful control of diabetes and regular eye exams can delay the development of the disorder. Diabetic retinopathy often develops without pain and with minimal symptoms at first. Because it can be treated after an early diagnosis, it is critical to have an annual eye exam and to report any change in vision.

What can be done if diabetic retinopathy is diagnosed? The best treatment for diabetic retinopathy is to control the blood sugar levels. If the blood vessels in the back of the eye are leaking, laser surgery can often seal off the leaks that lead to macular edema. If the condition has progressed to the point that the blood vessels are leaking into the vitreous humor, a vitrectomy can be performed.

What devices can help? Many people who have lost some vision can use video magnifiers and screen magnification programs to retain independence. For those who have lost most or all their sight, screen reading software is recommended. Because many people with diabetes also experience lessened sensitivity in their fingers, they do not usually use Braille.

TOPAZ Desktop Video Magnifiers allow you to read magazines and letters, view family photos, write checks, or engage in your favorite hobby, all in the comfort of your home or office.

RUBY Handheld Video Magnifiers can slip comfortably into a pocket or purse, giving you easy access to photos, letters, menus, prescription labels, and so much more, wherever you go.

ONYX Portable Video Magnifiers move from school to home to the office to help you see the board, read your assignments, take notes, do crafts, or to read, write, and view business presentations.

SAPPHIRE Handheld Video Magnifier magnifies bills, bank statements, and even three-dimensional items like food labels and pill bottles for continued independence.

MAGic Screen Magnification Software provides screen magnification and screen reading for low vision computer users.

JAWS Screen Reading Software is for computer users whose vision loss prevents them from seeing screen content or navigating with a mouse.

OpenBook Scanning and Reading Software provides access to documents or graphic-based text into on your PC so they can be read using high-quality speech.

SARA Scanning and Reading Appliances are self-contained appliances to read printed pages for people without computer experience who are blind or have low vision.

Glaucoma

Perhaps the most common eye disease in the world, glaucoma is a progressive condition that affects over 80 million people worldwide. People over 60 are at six times greater risk of developing glaucoma than the younger population, says the Glaucoma Research Foundation.

What is glaucoma? Glaucoma is characterized by damage to the optic nerve, resulting in unrelieved pressure inside the eye and fluid buildup. The cause is unknown but is probably genetic. Permanent impairment can range from loss of peripheral vision to severe vision loss. Individuals with glaucoma may experience increased frequency of headaches, blurred vision, halos around lights, difficulty seeing in dim lighting, and sometimes, a non-reactive pupil, pain, or even a swollen eye. However, the most common kind of glaucoma often has no apparent symptoms and no pain. When vision loss occurs, it usually happens slowly in the peripheral vision, so that people do not realize it is happening until the vision loss is quite advanced.

What can be done if glaucoma is diagnosed? Treatments commonly involve eye drops, beta blockers, oral medications, and/or surgery to relieve pressure. If left untreated, glaucoma can lead to blindness. While a cure is unknown, early diagnosis and treatment can save your eyesight to some extent.

What devices can help? Many people who lose their peripheral vision can benefit from a video magnifier. Because of the loss of peripheral vision, a large screen does not necessarily provide extra benefit. Often a small screen can be the most helpful. Therefore, handheld video magnifiers are often recommended.

RUBY Handheld Video Magnifiers can slip comfortably into a pocket or purse, giving you easy access to photos, letters, menus, prescription labels, and so much more, wherever you go.

TOPAZ Desktop Video Magnifiers, especially the 17” models, allow you to read magazines and letters, view family photos, write checks, or engage in your favorite hobby, all in the comfort of your home or office.

Age-related Macular Degeneration (AMD)

Age-related Macular Degeneration (AMD) is the foremost cause of vision loss among Americans who are 60 and older. AMD is not painful, so it is important to have your doctor perform a dilated eye exam regularly to catch AMD early. Warning signs of AMD include:

Lines that appear wavy or broken – even the edges of a square table or a book cover may appear distorted

Letters and numerals won’t come into focus

You see a dark spot in front of one or both eyes

What is AMD? Within the macula in the back of the eye is an area that contains the highest concentration of retinal cones, which produce the sharpest vision and are required to see details clearly. AMD results in damage to these cones. It is characterized by a worsening loss of central vision due to a growing “dark spot” seen directly in front of the eye, although peripheral vision may be clear. With Wet AMD, extra blood vessels form under the retina and grow and leak, causing visual impairment. Wet AMD is the most serious form of this eye disease and may occur suddenly. With Dry AMD, vision loss is slower. Dry AMD is the more common form, accounting for 90% of cases. Neither form of AMD causes complete blindness – you will always have some peripheral vision.

What can be done if AMD is diagnosed? Treatment can slow or stop the progression of AMD and vision loss. Treatments range from site injections to laser therapy. Several prescription drugs and therapies have shown promise to slightly improve visual acuity. However, nothing yet has been developed to reverse the effects of AMD.

What devices can help? Most people with AMD use aids to retain independence in their homes. Products include electronic magnifiers and devices that turn text into speech to read aloud mail, bills, books, and other printed materials. Freedom Scientific’s line of video magnifiers and screen magnification software can help.

TOPAZ Desktop Video Magnifiers allow you to read magazines and letters, view family photos, write checks, or engage in your favorite hobby, all in the comfort of your home or office.

RUBY Handheld Video Magnifiers can slip comfortably into a pocket or purse, giving you easy access to photos, letters, menus, prescription labels, and so much more, wherever you go.

ONYX Portable Video Magnifiers move from school to home to the office to help you see the board, read your assignments, take notes, do crafts, or to read, write, and view business presentations.

SAPPHIRE Handheld Video Magnifier magnifies bills, bank statements, and even three-dimensional items like food labels and pill bottles for continued independence.

MAGic Screen Magnification Software provides screen magnification and screen reading for low vision computer users.

SARA Scanning and Reading Appliances are self-contained appliances to read printed pages for people without computer experience who are blind or have low vision.

Retinitis Pigmentosa (RP)

Retinitis pigmentosa is a progressive eye disease found in over 100,000 people in the United States. It causes retinal degeneration and severe visual loss. RP causes a loss of part of the visual field, along with reduced night vision.

What is retinitis pigmentosa? Retinitis pigmentosa is an inherited eye disease, actually a group of inherited diseases. It often leads to severe visual impairment and sometimes total blindness. People with RP first develop noticeable symptoms in childhood or their teens. The first symptom most people notice is night blindness. The loss of vision is due to degeneration of the retina, specifically the rods and cones that serve as the light receptors. In most cases, the rods are affected first. Since rods are responsible for light and peripheral vision, most people find they need more light to see and perform tasks, and they cannot see well at night. When the cones are involved, the central vision and color perception are diminished. When retinitis pigmentosa occurs along with deafness, it is called Usher’s Syndrome.

What can be done if retinitis pigmentosa is diagnosed? There is no cure for retinitis pigmentosa, but some treatments exist to slow the progression of the disease. These mostly involve vitamin A supplements. Recent treatments include a retinal implant and retinal prosthesis. Recent research suggests that prolonged exposure to sunlight might increase the rate of vision loss, so people with RP are advised to wear sunglasses when outdoors.

What devices can help? For people with reduced vision due to retinitis pigmentosa, video magnifiers can help. They can provide both the magnification and the extra contrast and brightness to help with reading and other tasks. For those who have lost most or all their sight, screen reading software is recommended. Since retinitis pigmentosa usually begins in childhood, when people are still learning methods for reading, Braille is also a good solution.

TOPAZ Desktop Video Magnifiers allow you to read magazines and letters, view family photos, write checks, or engage in your favorite hobby, all in the comfort of your home or office.

RUBY Handheld Video Magnifiers can slip comfortably into a pocket or purse, giving you easy access to photos, letters, menus, prescription labels, and so much more, wherever you go.

ONYX Portable Video Magnifiers move from school to home to the office to help you see the board, read your assignments, take notes, do crafts, or to read, write, and view business presentations.

SAPPHIRE Handheld Video Magnifier magnifies bills, bank statements, and even three-dimensional items like food labels and pill bottles for continued independence.

MAGic Screen Magnification Software provides screen magnification and screen reading for low vision computer users.

JAWS Screen Reading Software is for computer users whose vision loss prevents them from seeing screen content or navigating with a mouse.

OpenBook Scanning and Reading Software provides access to documents or graphic-based text into on your PC so they can be read using high-quality speech.

SARA Scanning and Reading Appliances are self-contained appliances to read printed pages for people without computer experience who are blind or have low vision.

Stargardt Disease

Stargardt disease is the most common form of inherited juvenile macular degeneration, occurring in one in every 8,000 to 10,000 people worldwide. It causes gradual loss of central vision. It usually develops during childhood or adolescence, resulting in a loss of the central part of the visual field.

What is Stargardt disease? Stargardt disease is an inherited form of macular degeneration that first appears in childhood or adolescence. It is characterized by progressive vision loss beginning in the macula, the central part of the retina where light falls and visual acuity and color vision are greatest. Symptoms include blurred or wavy vision, blind spots, impaired color vision, and difficulty seeing in low light situations. People with Stargardt disease are usually sensitive to glare.

What can be done if Stargardt disease is diagnosed? There is no cure for Stargardt disease, and there are no treatments.

What devices can help? Since the symptoms are underlying physiology of Stargardt disease are similar to those for other types of macular degeneration, people can usually benefit from the same devices as used for age-related macular degeneration (AMD). These help people retain independence in their homes, school, and jobs. Products include electronic magnifiers and devices that turn text into speech to read aloud mail, bills, books, and other printed materials. Freedom Scientific’s line of video magnifiers and screen magnification software can help.

TOPAZ Desktop Video Magnifiers allow you to read magazines and letters, view family photos, write checks, or engage in your favorite hobby, all in the comfort of your home or office.

RUBY Handheld Video Magnifiers can slip comfortably into a pocket or purse, giving you easy access to photos, letters, menus, prescription labels, and so much more, wherever you go.

ONYX Portable Video Magnifiers move from school to home to the office to help you see the board, read your assignments, take notes, do crafts, or to read, write, and view business presentations.

SAPPHIRE Handheld Video Magnifier magnifies bills, bank statements, and even three-dimensional items like food labels and pill bottles for continued independence.

MAGic Screen Magnification Software provides screen magnification and screen reading for low vision computer users.

Blind vs. Visually Impaired: What’s the Difference? | IBVI

A look into the difference between what constitutes someone as visually impaired or blind

A question people ask often is, “What’s the difference between someone who is blind and someone who is visually impaired?” So, today, I sat down with our newest intern, Katie, to ask her some questions about the differences between visual impairment and blindness. She told me we should first start with the definitions of both.

What is the difference between visual impairment and blindness?

The definition of visual impairment is “a decrease in the ability to see to a certain degree that causes problems not fixable by usual means, such as glasses.” Blindness is “the state of being unable to see due to injury, disease or genetic condition.”

In the U.S., there are four terms used to describe different levels of vision impairment and blindness—partially sighted, low vision, legally blind and totally blind.

Partially sighted means a person has partial vision, either in one or both eyes.

Low vision refers to a severe visual impairment in which visual acuity is 20/70 or poorer in the better-seeing eye and cannot improve with glasses or contacts.

Legally blind means a person has a corrected vision of 20/200 in their best-seeing eye. If visual aids such as glasses can correct a person’s vision to 20/20, they are not considered legally blind.

Totally blind refers to a complete loss of sight.

While the phrase “visual acuity” may seem new to you, Katie explained that it is something most of us are familiar with. It is a measurement determined by the letter chart tests we take when we get our eyes checked; the number represents your eyes’ clarity or sharpness. For example, a person with a visual acuity measurement of 20/70who is 20 feet away from an eye chart sees what a person with 20/20 vision can see from 70 feet away.

Does a totally blind person with their eyes open see the same thing as a sighted person with their eyes closed?
Most people who are born blind say they see nothing. But, people who previously had vision before going blind say they usually see black and sometimes faded shapes, flashes of light or color, and experience vivid hallucinations.

From what distances are visually impaired people able to see?

It depends on the type of visual impairment someone is living with. For Katie and probably many others, objects are only visible from a certain distance—this distance could be as close as right in front of the eye or as far as 20 feet away. From a distance, objects may be blurry or faint. Some people may also see in tunnel vision, which is the loss of peripheral vision. Visual impairment can improve with glasses or other types of adaptive technology such as CyberEyez.

Can blind or visually impaired people still lead normal lives?

Absolutely! Many blind and visually impaired people adjust to their disabilities. Being visually impaired or blind doesn’t mean they can’t live normal lives just like anyone else. They work, go to the movies, explore new parts of town, and even win national talent contests.

Being blind or visually impaired isn’t about what they can or cannot do. It’s about learning the best way to accomplish whatever goals they set out to achieve.

Blindness: Causes and Types | Eye-Q Hospital

Blindness is the inability to see anything with your eyes, even light. This loss in vision could be due to an injury or accident. A person with partial blindness has limited vision. It must be noted that the term blindness is used in the relative form and for a person with visual impairment or low vision.

Causes of Blindness

The commonly known causes of blindness can be Glaucoma, age-related macular, degeneration corneal opacities, deficiency of Vitamin A, retinopathy of prematurity, vascular diseases involving the retina or optic nerve. Other possible reasons may include stroke, ocular inflammatory disease, retinitis pigmentosa (a genetic disorder in which retina is unable to respond to light), primary or secondary malignancies of the eye congenital abnormalities, hereditary diseases and chemical poisoning from toxic agents, such as methanol. Some of these are treatable or preventable with timely examination and treatment.

There are three commonly other types of blindness: Colour blindness, night blindness and snow blindness. In which special visual function are deprived but the patient can perform his daily activity in normal light.

Types of Blindness

The causes of all these types differ from each other.

Colour blindness – is the inability or the difficulty to perceive different shades of colours, specifically red and green. This is a genetic disorder and affects men more, as compared to women. People with colour blindness do not have a vision loss but lack of sense of colours.

Night blindness – refers to the difficulty of seeing in low and dim lights. Night blindness can be both genetic and acquired. The eye functions well in proper day-light or illuminated areas. This is not a case of complete blindness.

Snow blindness – is the loss of vision when exposed to ultraviolet light. This is a form of temporary blindness caused by swelling of cells in the corneal surface.

Another type of blindness is congenital blindness in which a person is born blind. It usually happens when the organ is not developed properly or due to some complications during pregnancy. In either of the cases, the person is born blind and cannot see due to underdeveloped organs.

Most cases of acquired blindness can be treated to a great extent. Choose EyeQ Vision’s Glaucoma Treatment Services and Retina Treatment Services to save your precious eyes, before it’s too late.

Types of visual impairment

The World Health Organization (WHO) International Classification of Impairment, Disabilities, and Handicaps (ICIDH) system is used to classify the types of visual impairment.

This system, as the name suggests, is used to classify disorders, impairments, disabilities, and handicaps.

Definition of impairment

Impairment is defined as “any loss or abnormality in an anatomical structure or a physiological or psychological function.”

Similarly a disability is “any restriction or lack (resulting from an impairment) of ability to perform an activity in the manner or within the range considered normal for a human being.”

This places an individual in a handicap that is a person’s disadvantaged position in society due to an impairment or disability.

Definition of visual impairment

Visual impairment is defined as the limitation of actions and functions of the visual system.

The National Eye Institute defines low vision as a visual impairment not correctable by standard glasses, contact lenses, medication or surgery that interferes with the ability to perform activities of daily living.

Types of visual impairment

According to the CDC and the World Health Organization the classification of visual acuity and impairment includes (1, 2) –

Low visual acuity means vision between 20/70 and 20/400 with the best possible correction, or a visual field of 20 degrees or less

Blindness is defined as a visual acuity worse than 20/400 with the best possible correction, or a visual field of 10 degrees or less

Legal blindness in the US means visual acuity of 20/200 or worse with the best possible correction, or a visual field of 20 degrees or less.

Visual acuity of 20/70 to 20/400 (inclusive) is considered moderate visual impairment or low vision.

Causes of visual impairment

Types of impairment are different for different causes of visual impairment. In total vision loss for example there may be total darkness of the visual fields. Other types include visual impairment in glaucoma, age-related macular degeneration and so forth. (1-5)

Visual impairment in glaucoma

This condition is due to the rise of normal fluid pressure inside the eyes. The type of vision is usually like a tunnel.

The intact vision remains in the center while progressively the peripheries start decreasing. The center of the tunnel reduces in size progressively till total vision is lost if left uncorrected.

Age-Related Macular Degeneration

A central area of woolly or cottony opacity obscures the central part of the vision.

The peripheries may be normally seen. AMD usually blurs the sharp, central vision that is needed for closely viewed activities like reading, sewing, and driving. This is a painless condition.

Cataract

There is general clouding of the vision. As the whole eye lens is affected the blurring of vision may be diffuse until it is totally lost.

There may be other symptoms like photophobia – inability to see the light; diplopia – double vision etc. Cataracts are very common in older people.

Diabetic Retinopathy

Diabetes leads to damage of the smaller arteries and blood vessels at the back of the eyes over the retina.

Diabetic retinopathy is the most common diabetic eye disease and a leading cause of blindness in adults.

Usually vision impairment in diabetics begins as black spots or floating shapes that appear in the field of vision. Slowly complete vision may be lost if left unchecked.

Near sightedness

Myopia or near sightedness or short sightedness means a person can see nearby objects clearly but distant objects appear blurred. High myopia may lead to vision impairment.

Retinitis Pigmentosa

This is a genetic or inherited condition. Initially it manifests as night blindness.

As the disease progresses there may be a tunnelling of vision with loss of peripheral vision followed by complete blindness.

Color Blindness: Signs and Symptoms

Do you find it difficult to distinguish between blue and yellow or red and green? Do they ever tell you that the color you think you see is completely different?

If yes, this indicates that you have a color vision deficiency.

Contrary to popular belief, color blind people who see everything in gray are rare.

Most people who are considered “color blind” can see colors, but they perceive some colors as washed out and easily confused with other colors, depending on what type of color vision deficit they have.

If you develop color vision impairment, although usually you could distinguish the entire spectrum of colors, then you definitely need to consult an optometrist.A sudden or gradual loss of color vision can indicate a number of health problems, such as developing cataracts.

A color blindness test will help determine what type of color vision deficiency you have.

CM. ALSO: Color Blind Spectacles

What Causes Color Blindness?

Color blindness occurs when light-sensitive cells in the retina do not respond appropriately to changes in the wavelength of light that allow people to see different colors.

Photoreceptors in the retina are called rods and cones. There are many more rods in the human retina (approximately 100 million), and they are more sensitive to light, but rods are not able to perceive colors.

About 6-7 million cones are responsible for color vision in the human retina; these photoreceptors are located in a central area of the retina called the macula.

The center of the macula is called fovea; this tiny area (0.3 mm in diameter) with the highest concentration of cones in the retina is responsible for our sharpest color vision.

Inherited forms of color blindness are often associated with a deficiency or absence of certain types of cones.

In addition to genetic differences, other causes of color vision defects or deficiencies include:

Parkinson’s disease (PD). Because Parkinson’s disease is a neurological disease, light-sensitive nerve cells in the retina that process vision can become damaged and lose their function.

Cataracts. Clouding of the natural lens of the eye from cataracts can cause blurred color vision, making colors appear less vivid. Fortunately, bright color vision can be restored with cataract surgery, during which the cloudy natural lens of the eye is removed and replaced with an artificial intraocular lens.

Certain medications. The anticonvulsant drug tiagabine has been shown to impair color vision in about 41 percent of people who took it, although this side effect disappears over time.

Leber hereditary optic neuropathy (NONL). In this type of hereditary optic neuropathy, some degree of color blindness can occur even in carriers of the disease who do not have any other symptoms. In this disease, a red-green deficiency in color perception is predominantly observed.

Kallman syndrome. This is an inherited disorder of the pituitary gland that can lead to incomplete or unusual gender development, such as the genitals. Color blindness can be one of the symptoms of this disease.

Color blindness can also develop when retinal cells are damaged during aging. Trauma or damage to areas of the brain that process visual information can also lead to color vision deficits.

Treatment options for color blindness

According to researchers at the University of Washington, monkeys were cured of color blindness using gene therapy.

While these results in animals look promising, gene therapy will not be used in humans until proven safe.

There are no treatment options for color blindness yet. But some strategies can help color blind people improve eye function in a colorful world.

Most people can easily adapt to color vision deficits. But some professions, such as those related to graphic design and working with electrical wiring of different colors, require accurate color perception.

If at an early age you realize that you are color blind, then it is worth choosing a career that does not require accurate color perception.

Diagnosing color vision deficiency at an early age can also prevent learning problems during school years, especially since many teaching materials are highly dependent on color perception.

If your child is color deficient, be sure to talk to their teachers so they can take this into account when preparing their lessons and presentations.

Lenses for color blind people

To enhance color perception, some people use special lenses that are filters and can be presented as contact lenses or spectacle lenses.

One example is the color blind glasses developed by EnChroma. EnChroma’s tinted lenses for colorblind glasses, made with a patented light filtering technology, allow people with common forms of color blindness to see a wide range of vibrant colors that most of us take for granted, the company said.

If you have a color vision deficiency, you should contact a nearby optometrist for advice on whether color blind glasses are suitable for you.

You can also learn how to get around the inability to distinguish certain colors. For example, you can sort your clothes so that you don’t wear mismatched colors. (Ask a friend or family member who has normal color vision to help you with this.)

Learn to recognize some colored objects by their order, not by color.In addition, there are

downloads of various apps designed for Android and Apple devices to help you determine the color.

See an optometrist for additional help and guidance if you have difficulty distinguishing colors or if you suspect your child may be color blind.

Is red-green color deficiency hereditary?

The most common inherited form of color vision deficiency is red-green color vision deficiency.It is caused by the fairly common X-linked recessive inheritance.

Mothers have a set of X-X chromosomes that carry genetic material, while fathers have a set of X-Y chromosomes. Both from the mother and from the father chromosomes are taken, which
determine the gender of the child.

When an X chromosome from one parent mates with an X chromosome from the other parent, the child will be a girl. When the X chromosome from the mother mates with the Y chromosome from the father, the baby will be a boy.

If you have X-linked recessive inheritance from red-green color vision deficiency, this means that your mother is a carrier of the gene or is color-blind herself.

With this inheritance of red-green color deficiency, fathers pass the X-linked gene to their daughters, but not to their sons, since the son cannot receive the X-linked genetic material from his father.

A daughter who inherits a gene for color blindness from her father will be a carrier of such a gene, but she herself will not be color blind – unless, of course, her mother is a carrier of the gene for color blindness, and she did not inherit it from her mother. If a daughter inherits X-linked characteristics from both her father and mother, then she will be color blind.

When a mother passes on this X-linked characteristic to her son, he will inherit a color vision deficit and it will be difficult for him to distinguish between red and green.

A daughter can also be a carrier, but she will develop this form of color blindness only if both the father and the mother pass on an X-linked gene to her. Therefore, there are more color-blind men than
women.

Page published in November 2020

Page updated April 2021

90,000 What is the difference between total and practical blindness?

A blind person is completely or partially lost the ability to see.Doctors classify blindness into several types, depending on whether at least minimal vision is preserved or not. In this article, we will discuss the difference between practical and total blindness.

In a blind person, as a result of pathologies of the eye, optic nerve or cerebral cortex, the ability to see is lost – to recognize visual stimuli. Interestingly, blindness is defined differently in different countries. According to the definition given by the World Health Organization, a patient is considered blind if his central vision is less than 3/60.With such a sharpness, it will not be possible to consider an object that is three meters from a person, even in very good lighting. In addition, blindness is also determined by the diameter of the visual field. In the blind, it is less than 10 degrees.

What is the difference between total and practical blindness?

The absolute absence or serious damage to visual function is commonly referred to as blindness. It can be total and practical.

Total means that a person sees absolutely nothing with two eyes.He has no light perception, he does not distinguish colors, he does not even see the blurred outlines of objects. In people with this diagnosis, the pupils do not respond to visual stimulation.

In a practical form, light perception (the ability to distinguish light from darkness) can be preserved, a person can see the outlines of other people, objects of the surrounding world.

With any form of blindness, a person’s capabilities are severely limited. Loss of vision affects the ability to navigate in space, move freely, independently perform any actions.

What could be the cause?

There are various causes of loss of vision. If blindness develops in a child, most often it is intrauterine or genetic pathology. In adults, pathology can be caused by traumatic eye injuries, inflammatory and non-inflammatory diseases. According to statistics, the most common cause of blindness in the world is cataract, or lens opacity. Another reason is glaucoma, in which the circulation of fluid in the eyes is disrupted and the optic nerve is damaged.

Blindness can be caused by diabetic retinopathy – damage to the retina, which is caused by pathological changes in blood vessels against the background of diabetes mellitus. Elderly people often lose their eyesight as a result of age-related degeneration of the retina – with this disease, the area of the highest visual acuity, the macula, is gradually destroyed. Common causes of infectious blindness are trachoma and onchocerciasis.

Trachoma is caused by chlamydia and affects the cornea and the connective membrane of the eyes.The disease is widespread in several developing countries. Onchocerciasis is parasitic and often causes blindness in South America and Africa.

In many cases, blindness can be prevented or delayed if you see your doctor early and start treating your eye problems.

Blindness in humans – why it occurs, methods of diagnosis and treatment

Blindness is the medical term for severe or no visual impairment.

With blindness, visual perception is impossible or significantly limited due to a significant narrowing of the visual field, as well as a decrease in central visual acuity.

In clinical practice, the following types of this pathology are distinguished:

Total or absolute blindness.
Practical blindness.

Complete blindness is a condition in which the visual sensations of both eyes are completely absent. With practical blindness, residual vision is present, color and light perception is preserved.

Causes of blindness

Fear of going blind, very often prompts suspicious people, when contacting doctors, to ask rather stupid questions, for example: can people go blind in a dream? At the same time, it will not be difficult for any competent specialist to explain that in absolutely healthy people, sudden blindness does not occur.This pathology can be the result of conditions and diseases such as:

There are also a number of specific types of blindness:

Color blindness. This is an anomaly in which a person cannot distinguish colors that others can easily distinguish. Pathology, as a rule, is genetically predetermined and is transmitted through the male line. According to statistics, it is detected in almost 8% of men, in women, but this figure is less than 1%. Moreover, in such patients, in most cases, visual acuity remains normal.

Night blindness. With this pathology, a person loses the ability to distinguish surrounding objects at dusk. Such a violation can be of both a genetic nature and develop as a result of a number of diseases. The overwhelming majority of patients with night blindness, in the daytime, have normal visual acuity. Therefore, it is rather difficult to call such a phenomenon blindness.

Snow blindness. This is a deterioration or complete absence of visual perception with a powerful effect on vision of UV rays.Most often, such a violation resembles over time due to the overgrowth of the tissues of the surface of the cornea. Snow loss of vision is a temporary phenomenon and never leads to absolute blindness. The movement of objects, bright light, the outlines of objects, people can see in any case.

Blindness, as a pathology of vision, can be temporary and permanent. In order to determine the degree of impairment, measure the visual field, as well as the acuity of perception, separately for each eye. The ability to see, sometimes it can suddenly disappear, or deteriorate slowly (when the cause is a disease), gradually being completely lost.In any case, it is necessary to visit an ophthalmologist to determine the degree of blindness. It must be remembered that some types of even complete blindness are reversible. However, when a patient is diagnosed with a dysfunction of the optic nerve, as well as in the event of a cerebral hemorrhage, it is almost impossible to restore vision.

Diagnostics

A person is recognized as blind if he has no visual sensations completely, or in the presence of light sensations or residual vision (0.01D – 0.05D), on an eye that can see with spectacle correction.Blinded people lose the ability to distinguish some characteristics of objects: light, color, size and shape, location of objects. They experience serious difficulties in orientation in space (distance, direction, movement, etc.). All this becomes the reason for the impoverishment of sensory experience, makes it difficult for them to move. At the same time, in the blind, the reaction to sound is significantly enhanced, since sounds are a very important factor in orientation in the world around them.

Due to blindness, there is a delay in movement.Many blind people report negative emotional changes. In the process of getting used to the lack of vision, a person usually overcomes the negative phenomena of a new state, forming other ways of recognizing the surrounding reality with the involvement of auditory, motor, skin and other analyzers. Now it is they that form the basis for the development of complex mental processes – generalized perception, voluntary attention, abstract thinking and logical memory.All this allows the blind to perceive reality correctly. During orientation, as well as in the formation of figurative thinking, as before, visual representations preserved in the memory of a blind person play a significant role.

Treatment

Complete blindness resulting from damage to the optic nerve or a stroke is not amenable to treatment. In such cases, unfortunately, it is impossible to restore vision.

To improve the quality of life of blind patients, special tools designed to facilitate their daily life are called upon: books and manuals written in Braille (today there are electronic versions), computer programs, as well as a number of devices that significantly expand the capabilities of the blind (completely blind and have weak vision).

Sudden blindness is always a severe psychological trauma, which is often accompanied by prolonged depression. Therefore, therapeutic measures should be carried out not only by an ophthalmologist, but also by a psychiatrist.

Modern ophthalmology does not yet have methods of treating congenital color blindness. With its acquired form, elimination of the reasons that led to its development is required. Sometimes, vision improvement can occur after discontinuation of a particular medication.

Prevention

With a certain amount of knowledge and the ability to receive high-quality medical care, the onset of blindness can be prevented.

Blindness resulting from injury is prevented by strict adherence to the instructions for eye protection. Forms of essential blindness can be eliminated by adjusting the diet. Early detection of cataracts and glaucoma, with regular treatment, will avoid blindness associated with these diseases.Controlling your blood sugar and maintaining your own weight, as well as exercising, quitting smoking and following a certain diet, will help you avoid blindness from diabetic retinopathy.

Due to all of the above problems, advice should be given to spend more time outdoors. Due to this, the organ of vision rests, and the body is strengthened. This is a very good prevention of all systemic pathologies. You can also try traditional eye care methods, including lotions and drops.In this case, you should carefully monitor your health. At the first symptoms of a change in eye color, you should immediately make an appointment with a specialist and conduct an examination.

At the Moscow Eye Clinic medical center, everyone can be examined using the most modern diagnostic equipment, and based on the results, they can get advice from a highly qualified specialist. The clinic consults children from 4 years old. We are open seven days a week and work daily from 9 am to 9 pm.Our experts will help you identify the cause of your vision loss, and will provide competent treatment for the identified pathologies.

To clarify the cost of a particular procedure, make an appointment at the Moscow Eye Clinic, you can call 8 800 777-38-81 (daily from 9:00 to 21:00, free of charge for mobile phones and regions of the Russian Federation) or using the online form -records.

90,000 Impaired perception of shades of red and green, red-green color blindness and complete color blindness

Not all forms of color blindness are created equal.Depending on the causes and symptoms, color vision impairment, partial color blindness and complete color blindness are distinguished. Color impairment can be congenital or acquired. For example: Many color identification difficulties are the result of eye diseases such as macular degeneration. Also, problems with color perception can be associated with prolonged use of certain medications or diseases that affect the optic nerve. This includes atrophy of the optic nerve, i.e. atrophy of the optic nerve.e. death of photoreceptor cells in the optic nerve. It can be caused by various reasons, incl. inflammation of the optic nerve, increased pressure in the brain or alcohol intoxication. Age-related clouding of the lens of the eye and changes in the brain can also limit our ability to distinguish colors.

People with congenital color vision disorders notice this only after a large part of their life with this condition. During a casual conversation with a person who has normal color perception (“it seems more blue… “), or when performing a task that requires accurate color sorting, a person with a color vision disorder may realize that they perceive the world differently from other people. Many professions require good color vision and therefore cannot be performed by people with color blindness or color vision disorders. These professions include police officers, painters, painters, CAD people, dentists, electricians, and laboratory chemists. Excellent color vision is also a must for many creative / design professions and in the fashion industry.For this reason, when recruiting for many positions, incl. in the transportation industry, job seekers are tested for color blindness. Prospective pilots and people seeking a motorized boat license must also prove that they are not color blind.

90,000 Surgical treatment of glaucoma: how to defeat the most insidious eye disease?

From March 9 to 17, Moscow will host a week of fighting glaucoma – a group of severe chronic eye diseases united by common symptoms: increased eye pressure, trophic disorders of the optic nerve and retina, decreased visual acuity and narrowing of visual fields.Andrey Vladimirovich Lapochkin, an ophthalmologist, Ph.D.

Why is glaucoma given so much attention out of all ophthalmic diseases?

Firstly, this is a fairly common group of diseases: according to statistics, 2-3% of the world’s population suffers from glaucoma.Secondly, this insidious disease is one of the first among the causes of incurable blindness. In the early stages, the disease develops imperceptibly: the eye does not hurt, does not blush, does not give cause for concern – but at the same time, a slow, systematic death of the optic nerve and retina gradually occurs. Usually, at the moment when the patient notices alarming symptoms – a sharp narrowing of the field of vision, impaired visual acuity – we are forced to state that about 70% of the optic nerve has already died.In such situations, we are faced with the only task – to preserve the remaining vision.

Who is most at risk for this disease?

Glaucoma is an age-related disease, most often diagnosed in patients who have reached 55-60 years of age. However, now all over the world there is a tendency towards the rejuvenation of various chronic diseases, including diseases of the organs of vision – glaucoma, cataracts. In some cases, glaucoma is diagnosed in patients 35-40 years old.In essence, this is a vascular disease, therefore, patients suffering from diabetes mellitus and arterial hypertension are at risk. In addition, the hereditary factor plays an important role: if one of your older relatives has been diagnosed with glaucoma, you should be more careful about the health of your eyes.

If symptoms appear too late, then how can you protect yourself from glaucoma?

All that can be done in order not to “miss” the onset of the disease is to undergo regular scheduled diagnostic examinations of the organs of vision.If you have no complaints, you are shown to be examined by an ophthalmologist at least once a year. Moreover, the examination must include a procedure for measuring eye pressure. It is the increased eye pressure that is the main symptom of a developing disease. Citizens over the age of 45 are advised to have their eye pressure measured once a year, regardless of whether they are satisfied with the quality of their vision.

Can routine preventive examinations by a district ophthalmologist help in the early diagnosis of glaucoma?

Of course, if the necessary equipment is available, the district ophthalmologist will notice the first symptoms of glaucoma in the patient.On the other hand, it takes an average of 45-50 minutes for a detailed examination and diagnosis of the eyes: an ophthalmologist in a polyclinic often does not have such a margin of time. If you find any alarming symptoms, the doctor will refer you to the Consultative and Diagnostic Center, where you can conduct a more detailed examination and get detailed advice. In the CDC, the diagnosis is clarified and a decision is made on the need for surgical treatment of glaucoma.

Does glaucoma always have to be operated on?

Any surgical intervention is justified when other methods are powerless.Fortunately, modern medicine has a large arsenal of therapeutic drugs that can successfully fight the development of glaucoma. First of all, the task of these drugs is to reduce eye pressure, since otherwise the optic nerve and retina are systematically compressed, which is why the patient gradually loses his vision. Also, an important part of drug therapy is vascular drugs designed to improve the blood supply to the retina and optic nerve.

However, from an economic point of view, conservative treatment of glaucoma is not the most affordable pleasure.Good drugs for glaucoma are expensive, moreover, more often than not, an ophthalmologist cannot limit himself to just one drug: the patient is prescribed up to 4 types of expensive drops that normalize eye pressure. Let’s not forget that our patient, as a rule, is a citizen of retirement age. Therefore, there are often situations when the patient cannot afford to maintain vision with the help of therapy, and then surgery will be the optimal solution for him.

What is glaucoma surgery?

Glaucoma is a group of diseases that are associated with obstruction of the outflow of ocular fluid.There are natural outflow pathways in the eye – trabeculae, thanks to which a balance of pressure is maintained in a healthy eye. In glaucoma, the natural outflow pathways gradually cease to function normally. During the operation of glaucoma, an ophthalmologist surgeon creates an artificial fluid outflow channel – a fistula, which will help to establish the outflow of ocular fluid for a certain period, from several months to 10-15 years.

Is it possible to predict how effective the operation will be and how long the artificial drainage channel of the eye fluid will last?

Unfortunately, modern medicine does not have methods that can predict the effectiveness of this operation.The main problem is that for the body, the fistula we have created is a wound that should heal over time. Naturally, after the operation, all patients must take special drugs to slow down the process of scarring of artificial ways of outflow of the ophthalmic fluid, but the degree of effectiveness of these drugs in each individual case may be different.

That is, the skill of the surgeon cannot provide a high effect of the operation?

The skill of the surgeon is extremely important.Nevertheless, it is possible to carry out the operation brilliantly and achieve success for a period of no more than a year or two. Only regular postoperative observation will allow the ophthalmologist to monitor the condition of the glaucomatous eye. Depending on the condition of the eye after the operation, the doctor decides how to adjust the drug therapy, whether it is necessary to think about a second operation. The situation is complicated by the fact that in elderly patients, as a rule, several complicating pathologies develop in the same eye.For example, in 20-30% of cases, glaucoma develops in parallel with cataracts – a disease that also quite often requires surgical treatment.

Is cataract also difficult to detect in the early stages?

Unlike glaucoma, cataracts make themselves felt. Its main symptoms are a gradual decrease, blurred vision, the glasses, which he usually wears, no longer help the patient.

There are several grades of cataract. At the initial stage, when vision decreases slightly, the disease is only subject to close observation.However, sometimes, even at this stage, patients agree to undergo surgery to get rid of discomfort.

The second stage – “immature cataract” – the optimal time for surgical treatment: at this stage, the operation will be carried out quickly enough and with a high guarantee of efficiency. A mature or complicated cataract is considered a more advanced stage. There are different types of complications: swelling cataract tends to swell like a ball due to the absorbed ocular fluid; with brown cataract the lens of the eye literally reaches stone hardness.Mature and complicated cataracts are much more difficult to operate. True, domestic ophthalmological surgeons have quite a lot of experience in surgery even at this stage, since our patients tend to delay treatment and postpone going to the doctor. Of course, the operation will be easier and will give the best effect, if you do not bring yourself to complete blindness.

Fortunately, most of the vision is restored with cataracts. Operations for cataracts are much more predictable than in the case of glaucoma: if the patient has no concomitant eye diseases, we can count on a good effect.

Cataracts often reveal glaucoma: the patient begins to complain of decreased vision, undergoes a comprehensive examination – and it necessarily includes the measurement of eye pressure. Thus, if both cataracts and glaucoma develop in the same eye, the first helps to identify the second.

But what if a patient has both diseases in the same eye requiring surgical treatment?

As a rule, a combined operation is performed in such cases.The difficulty is that cataract and glaucoma operations differ significantly in technology. Therefore, this type of surgery should only be performed by the hands of very experienced surgeons.

Standardized cataract surgery – ultrasonic phacoemulsification – is performed using ultrasound. This is a modern endoscopic method that allows the operation to be performed through a puncture with a diameter of no more than 2 mm, without further suturing. Through this small puncture, a flexible artificial lens is implanted into the eye.The recovery period after such an operation is about a month, and the patient notices the first positive results already on the second day after the operation.

It must be said that, although ultrasound is the “gold standard” of cataract surgery, sometimes extracapsular cataract extraction is more predictable – the older method, in which the incision reaches ten millimeters, you have to suture – but despite this, this is the method turns out to be more effective in a number of advanced cases.

How affordable are all these ophthalmic operations for Muscovites?

We operate both cataracts and glaucoma according to the compulsory medical insurance, with certain indications. If the patient wants to get to the operation as soon as possible, or, for example, wants to implant a more expensive model of the lens, he contacts the paid services department.

The waiting time for a cataract operation under the compulsory medical insurance program is on average 6-8 months: this is how much it takes from the initial diagnosis by a district ophthalmologist to the day of the operation, including all preoperative examinations.By the way, in comparison with other European countries, this is a fairly short period: in the UK, for example, a free cataract operation on is expected on average for about 2 years.

As for glaucoma, here we are talking about irreversible blindness, which means that the case is more urgent than cataract. If, according to the observation results, the level of eye pressure is consistently high, and conservative treatment does not bring the expected effect, then the patient’s path from diagnosis to surgery will be as short as possible – about two to three weeks.If the situation is less “acute”, the patient will be operated on as planned, usually within two to three months from the date of diagnosis.

For what reason can a patient be refused an ophthalmic operation?

In the case of both cataracts and glaucoma, the complexity and neglect of the situation is not a contraindication: in any case, the specialists of the Botkin Hospital do an excellent job with such complicated tasks. In general, Russian surgical experience is much superior to that of many Western surgeons, precisely for the reason that we often have to work with very advanced cases.

The main argument in favor of the operation is the progression of the disease. As soon as a patient is diagnosed with glaucoma, we recommend that he undergo dispensary observation: about 3 times a year, he should, while on drug therapy, undergo an examination by an ophthalmologist surgeon. If during the examinations we see that the disease has stabilized, the operation can be postponed, or even avoided. If the disease progresses, the patient is shown surgical treatment.

Are there any special methods, technologies for surgical treatment of glaucoma in Russia?

For more than 20 years, the author’s method of glaucoma operation has been widely used in surgery, which was invented by my father, Doctor of Medical Sciences Vladimir Ivanovich Lapochkin.The operation was developed on the basis of his rich clinical experience in the field of ophthalmology and surgery, and is called DALS: draining autovalve limbsclerectomy). The peculiarity of this operation is in the activation of two pathways for the outflow of the eye fluid instead of one. Usually, during antiglaucoma surgery, one pathway for the outflow of eye fluid is formed – under the conjunctiva, that is, under the mucous membrane of the eye. The DALS method provides for a second, uveoscleral outflow canal.

Author’s DALS operation is performed only by doctors of your dynasty, or do you train other specialists?

Operation DALS is an experience that is important and rewarding to share.Now this method is widely used by Russian ophthalmological surgeons. We often talk about it at professional conferences, we record videos for colleagues in which each stage is described in detail, shown and explained.

What can be done at the moment to refine the method even more, to make it more efficient?

At one time, together with my father and brother (Dmitry Vladimirovich Lapochkin – ophthalmologist, clinical experience of 9 years) set a goal to popularize and standardize our patented operation.The idea arose to create a unique set of disposable instruments for this antiglaucoma operation. The fact is that every ophthalmologist in his practice chooses his “favorite” set of instruments himself – but not always a favorite instrument is optimal. In cooperation with a Russian plant that produces disposable medical instruments, we have begun to develop such a set of instruments. For a year and a half, we gave ideas and technical specifications, we received prototypes in response, then we tried the tools on pig’s eyes – and in the end we formed the final set.It contains nine disposable instruments that are best suited for DALS glaucoma surgery. At the moment, recruitment is going through the final registration stage.

What tangible results will be achieved when the disposable instrument kit is registered?

The main result is a guarantee that even a young specialist with the help of these tools can easily master the technology. Each instrument is designed specifically for a specific step of the operation, all instruments from the set are dosed to a certain depth – thus, it is impossible to “cut through the eye tissue” beyond the required level.Then, the disposable kit reduces the risk of postoperative infection. Finally, this is a significant contribution to the import substitution program in the field of medicine. At the moment, the work of Russian ophthalmologists is 95% dependent on imported disposable instruments. In our set, some instruments simply have no analogues in Europe – while others are successfully replacing European ones.

Useful links:

Patient’s school. Glaucoma

90,000 Blindness – signs, causes, symptoms, treatment and prevention

Symptoms

Gradual or sharp (depending on the cause) deterioration of vision leads to its complete absence.Sometimes the patient can feel the difference between very bright light and darkness, sometimes not. But this practically does not affect his ability to interact with the world, therefore, residual vision is also usually classified as blindness. Hearing and other senses are gradually sharpened.

Diagnostics

Diagnostics of the disease includes, first of all, checking visual acuity and visual field. If the visual system deteriorates, you should make an appointment with an ophthalmologist as soon as possible, because blindness is an extreme degree of many diseases and eye problems.

It is often irreversible, especially in the case of damage to the optic nerve, such as in progressive glaucoma. Therefore, it is better to start treating the cause of the disease in a timely manner.

Treatment

Having signed up for a consultation with an ophthalmologist and having passed all the necessary examinations, the patient receives an individual course of treatment, which depends on the source of the problem. For example, deterioration of the visual system caused by cataracts is treated with surgery. The consequences of poor nutrition are normalized by diet.Glaukoma, for example, can only be slowed down, so it is important not to wait for its terminal stage, but to start fighting diseases as early as possible. Infectious diseases are treated therapeutically.

Prophylaxis

The eyes are a very sensitive organ.

The sooner a person takes measures to improve eye health, the more chances that the lack of visual activity will remain unknown to him. The state of the visual system must be monitored, noting changes and contacting a doctor in case of problems.

In addition, nutrition should be monitored so that the diet remains balanced, for example, add blueberries, carrots, foods rich in vitamin A to the diet.

Literature and Sources

Ostrovsky V.M. Blindness // Brockhaus and Efron Encyclopedic Dictionary : in 86 volumes (82 volumes and 4 additional). – SPb., 1890-1907.

N. Kuznetsov. Blindness // Great Soviet Encyclopedia: In 65 volumes / ed. K. E. Voroshilov, A. Ya. Vyshinsky, P. I. Lebedev-Polyansky, A. Lozovsky, F.N. Petrov, F. A. Rotshtein, O. Yu. Schmidt, Em. Yaroslavsky. – 1st ed. – M .: State Scientific Institute “Soviet Encyclopedia”, 1945. – T. 51 (Serna – Contemplation). – S. 385-387. – 846 p. – 45,000 copies

Blindness // Great Soviet Encyclopedia: [in 30 volumes] / Ch. ed. A.M. Prokhorov. – 3rd ed. – M.: Soviet Encyclopedia, 1969-1978.

Related Videos:

90,000 Diseases of the retina – types, diagnosis and treatment

Stock! Discount 20% on the first appointment for new patients of the clinic with the promo code “FIRST20”.

One of the most important structures of the eye is the retina (retina). This is its inner shell, which is sensitive to light and converts the light signal into an image. This thin shell contains many nerve cells and special photoreceptors of several types. They allow you to see the world in colors and in darkness, navigate in space, examine objects near and far.

Any disease and pathology of the retina lead to visual impairment, up to complete blindness.We will tell you about the main diseases of the retina, their symptoms, treatment tactics and prevention.

Symptoms

Symptoms of diseases of the retina are hardly noticeable at the initial stages of the disease. Obvious complaints of vision appear when the deep layers of the membrane are affected. Complaints differ depending on the disease.

Main symptoms:

Decreased visual acuity at dusk.
Color recognition disorder – color blindness.
Narrowing of the lateral fields of view.
Visual distortion – glare, flares, black or colored spots, and other defects.
Deterioration of central vision.
The appearance of blind spots.
Short-term loss of vision in one of the eyes.
The appearance of a veil on the eyes.

Reasons

There are three main factors that lead to the formation of retinal diseases:

Infections that cause inflammation in the tissues of the eyes.
Congenital or acquired pathologies in photoreceptors due to which their structure changes, and the retina itself becomes thinner, cracked, torn.
Vascular pathologies associated with atherosclerosis, high blood pressure.

Retinal disorders are more common in patients with myopia, in which the retina is stretched.

Major diseases of the retina

There are more than a dozen of them in total, we talk about the main ones.

Retinal dystrophy

This is a group of diseases that are typical for the elderly or patients with myopia.These are stretching and thinning of areas of the retina, a decrease in its density and a violation of the anatomical relationship between the layers.

Among the causes of the disease are old age, cardiovascular pathologies, genetic predisposition.

Symptoms: blurred vision, blurred and disappearing areas, curvature of the contours of objects.

Retinal detachment

In this case, the shell ruptures and fluid accumulates. As a result of a deterioration in nutrition, the work of the retinal photoreceptors is disrupted.

Delamination can be:

Primary – due to the appearance of breaks in the retina.
Secondary – for tumors, injuries.

Symptoms of the disease are visual distortions: flies, sparks, flashes and other floating elements in front of the eyes, a one-sided shadow may appear before the eyes.

Rupture of the retina

In most cases, it appears against the background of changes in the eyeball with myopia. The retina is mechanically stretched, torn, exfoliates at the site of rupture.

Symptoms: light flashes, black threads in the image, decreased vision.

Chorioretinitis

Inflammation of the retina (retina). It covers both the membrane itself and the blood vessels that feed it. There may be retinitis pigmentosa or pigmentary abiotrophy (degenerative changes).

Symptoms: color distortion, indistinct contours of objects, severe visual impairment in individual visual segments, flashes in front of the eyes, decreased twilight vision.

Macular degeneration

This is a deterioration in the nutrition of the central region of the retina.

Symptoms: a veil in front of the eyes, blurred vision, vision in faded shades of colors, a noticeable lack of light even during the day, distortion of objects.

Retinal angiopathy

Pathology of the vascular walls, which leads to disruption of the normal blood circulation in the eyes. The retinal vessels become narrow, tortuous, both blood flow and outflow are disturbed, nutritional deficiency and blood stagnation occur.

Among the causes of pathology – diabetes mellitus, hypertension, osteochondrosis of the cervical spine and some other common diseases, eye injuries.

Symptoms: flies and spots before the eyes, deterioration in visual acuity, blurred vision, temporary or permanent narrowing of the field of vision.

Diabetic retinopathy

This is the result of an eye complication from diabetes. The disease is based on changes in the tone and elasticity of blood vessels, their destruction and reduction of the lumen. The supply of oxygen and nutrients deteriorates, and oxygen starvation of the retina sets in.

Symptoms: decreased vision, spots and other distortions before the eyes, blurred and veiled images.Symptoms appear gradually and imperceptibly for the patient against the background of high blood sugar.

Potential consequences include retinal detachment and blindness.

Retinal hemorrhage

They are caused by seals in the vessels, the formation of blood clots and other vascular pathologies. They increase the risk of dystrophy and retinal detachment, glaucoma and other ophthalmic pathologies.

Diagnostics

To assess the state of the retina, identify signs of its damage and make a diagnosis, it is carried out:

Assessment of visual acuity.
Determination of fields of view.
Examination of the fundus, retina and other structures of the eye.

Refractometry, perimetry, visometry, ultrasound of the eyeballs and other diagnostic methods are carried out, which allow a comprehensive assessment of the condition of the eye and visual impairment.

At the reception, the ophthalmologist may recommend that the patient contact other specialists of the clinic and undergo examinations to find the causes of the disease. It can be diabetes mellitus, hypertension and other pathologies that negatively affect the eyes.This will allow prescribing treatment not only for the consequences, but also for the root causes of diseases, to avoid further progression and relapses.

Treatment of diseases of the retina

Various methods are used for treatment:

Conservative therapy to maintain visual functions, improve blood circulation and nutrition of eye tissues, relieve vascular spasms. Antibiotics, anti-inflammatory and other drugs are prescribed if inflammation is the cause of the disease.
Laser therapy – coagulation of the retina in pathological areas where retinal detachment is possible or has already occurred. Laser techniques are used in the treatment of diabetic retinopathy, retinal detachment and other diseases, but may be contraindicated in some patients for a number of reasons.

It is also desirable to pay attention to the treatment of the root cause of the disease – normalization of blood glucose levels, lowering blood pressure to normal. This will slow down the progression of retinal pathologies, give a more pronounced and long-term result of treatment, and avoid complications.

Treatment of retinal diseases in the medical center “Kutuzovsky”

The clinic’s specialists are ready to carry out in a short time a comprehensive diagnostics of vision using the necessary examinations or a specially developed program “Ophthalmological Check Up”. The medical center is equipped with modern diagnostic equipment, which allows you to be confident in the accuracy of the results and the correctness of the prescribed treatment. In the medical center “Kutuzovsky” there are specialists of the right profile to take care of the health of the eyes and other organs and systems.It is possible to work jointly with the patient of several doctors with the coordination of appointments.

We work with patients on VHI policies, we accept them by appointment at a time convenient for you. To clarify the cost of consultation and diagnostic programs, you can make an appointment by calling the clinic’s call center: +7 (495) 478-10-03.

The address of the Kutuzovsky medical center: Moscow, Davydkovskaya street, 5 (reference point is the Slavyansky Boulevard metro station).

Prices

Name	Price
Appointment (examination, consultation) of an ophthalmologist, primary	1 750 ₽
Appointment (examination, consultation) of an ophthalmologist repeated	1 550 ₽

Different types of blindness: What blindness really looks like

What blindness really looks like

CVI: The leading cause of blindness in children

What learning with CVI looks like

Blindness and vision impairment

Definitions

Prevalence

Causes

Impact of vision impairment

Strategies to address eye conditions to avoid vision impairment

WHO response

References

Types of Blindness | Low vision

Types of Visual Impairment

Blind vs. Visually Impaired: What’s the Difference? | IBVI

A look into the difference between what constitutes someone as visually impaired or blind

Blindness: Causes and Types | Eye-Q Hospital

Types of visual impairment

Definition of impairment

Definition of visual impairment

Types of visual impairment

Causes of visual impairment

Visual impairment in glaucoma

Age-Related Macular Degeneration

Cataract

Diabetic Retinopathy

Near sightedness

Retinitis Pigmentosa

Further Reading

Color Blindness: Signs and Symptoms

What Causes Color Blindness?

Treatment options for color blindness

Lenses for color blind people

Is red-green color deficiency hereditary?

What is the difference between total and practical blindness?

What could be the cause?

Blindness in humans – why it occurs, methods of diagnosis and treatment

Causes of blindness

Diagnostics

Prevention

Symptoms

Diagnostics

Treatment

Prophylaxis

Literature and Sources

Symptoms

Reasons

Major diseases of the retina

Retinal dystrophy

Retinal detachment

Rupture of the retina

Chorioretinitis

Macular degeneration

Retinal angiopathy

Diabetic retinopathy

Retinal hemorrhage

Diagnostics

Treatment of diseases of the retina

Treatment of retinal diseases in the medical center “Kutuzovsky”

Prices

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