Vision impairment is found amongst the top ten disabilities in the US amongst adults 18 years and older. Though this fact alone is upsetting enough, the situation of vision disabilities worsening due to optic nerve damage and eye conditions in children younger than 18 is more disturbing.
The ratio of children younger than 18 years with a diagnosed eye condition is around 6.8% according to the Centers for Disease Control and Prevention (CDC). This means that around 547,083 children in the United States are living with vision difficulties according to the American Community Survey (ACS) 2019. Alarming, isn’t it?
What Causes Low Vision?
Human vision is mainly controlled by the optic nerve, also known as the second cranial nerve. It is a bundle of more than a million nerve fibers present at the back of the eye which sends sensory information for vision from the eye in the form of electrical impulses to the brain.
If the optic nerve is pressed or damaged, it can result in vision loss. The type and severity of vision loss depend on the place where the damage has occurred.
There are several factors involved in damaging the optic nerve. These include elevated pressure in the eye, trauma, injury, shock, poor blood flow, radiation, toxins, and various eye diseases. The diseases of the brain and central nervous system can also cause optic nerve damage. These diseases include:
- Temporal arteritis
- Brain tumors
- Multiple sclerosis
- Cerebrovascular Accident (CVA)
Optic nerve damage is most commonly caused by severe eye conditions such as glaucoma, optic neuritis, optic nerve atrophy, and optic nerve drusen.
Glaucoma is an outcome of fluid pressure build up in the eye. This rising pressure in the eye, termed the intraocular pressure, tends to damage the optic nerve which is responsible for sending images/visual information from the eyes to your brain. If the damage to the optic nerve continues to worsen, it can lead to permanent blindness.
Optic Neuritis refers to the inflammation of the optic nerve. You can interpret visual images when your optic nerve sends messages from your eyes to your brain. Irritation or swelling of the optic nerve inhibits this transmission of messages to the brain, hence causing unclear, blurred vision.
Optic Nerve Atrophy
Optic nerve atrophy is mild to acute damage to the optic nerve. This damage has a detrimental effect on central, peripheral, and color vision. A tumor, trauma, improper oxygen or blood supply, inflammation, infection, toxins, or rare degenerative disease can lead to optic nerve atrophy causing blurred vision and a decrease in visual acuity.
Optic Nerve Head Drusen
The abnormal accumulation of calcium and protein within the optic nerve leads to optic nerve head drusen causing visual field loss consequently. Peripheral vision loss is the most common effect of the optic nerve head drusen. Dimmed vision, blind spots, and generalized constriction might be an indication of the disease.
Effects of Low Vision
Low vision is an alarming indicator of a number of inconveniences linked to it. The complications connected to low vision are as follows:
Central Vision Loss
Central vision loss refers to a blind/dark spot in the center of the eye which grows in size over time. In this case, the detailed vision of a person is lost making it difficult for them to read hoardings, menu cards, or faces of the people around them. However, a person with central vision loss can still move around independently as the peripheral vision (side vision) remains unaffected.
Peripheral Vision Loss
When a person loses their peripheral vision, they are unable to see the objects and faces until they are right in front of them. The constricted circular field of vision due to peripheral vision loss is also termed as tunnel vision, which largely affects mobility.
Nyctalopia, commonly known as night blindness, refers to the inability of a person to see clearly at night or in a dimly lit indoor setting such as a movie theater.
Lack of sharpness of vision is referred to as blurred vision. A person with blurred vision is unable to see the minute and fine details of their surroundings. Blurred vision in most cases is due to nearsightedness or farsightedness, while in some cases it signals serious eye conditions.
Glare Light Sensitivity
Glare light sensitivity refers to the loss of visual acuity in bright lighting. A person with glare light sensitivity sees a washed-out image or a glare as the standard light overpowers their visual system. In adults, glare sensitivity is often caused by cataracts.
How to Prevent Vision Loss?
Vision problems do not always knock at your door before showing up. Rather, in most cases, vision problems break in and a person becomes aware of its presence when it is too late. The human eye goes through drastic changes as a person ages. These changes can dramatically affect vision or even lead to blindness.
However, there are a few simple preventive measures that can avert these vision problems.
Keep a check on your blood sugar levels: According to the Centers for disease control and prevention (CDC), about 90% of cases of blindness due to diabetic eye disorders can be prevented by early detection and intervention. By keeping the ABCs of diabetes i.e, blood sugar, blood pressure, and cholesterol in check, one can prevent vision loss and blindness that the diabetic eye diseases cause.
Maintain healthy eating habits: Those carrots you have been eating for a better vision are good but not enough! Add leafy green vegetables such as spinach or kale, fruits, and vitamin-enriched foods to your plate. Omega 3s are also great for the eyes, hence add fish high in omega 3 fatty acids such as tuna or salmon in your diet.
Refrain from Smoking: Research has proven that there is an undeniable link between smoking and some serious eye conditions such as macular degeneration, cataracts, and optic nerve damage. All of these severe diseases can eventually lead to blindness. The cyanide present in the cigarette smoke goes into the bloodstream and destroys the cells of the eyes.
Let your eyes rest: Keeping your eyes glued to the screen for long periods of time can lead to dry eyes as a person does not blink much while viewing a screen up close. The 20-20-20 rule is recommended while working for a longer time on the screen. According to this rule, after watching the screen for straight 20 minutes, the person should look at something that is 20 feet away for 20 seconds.
Get regular comprehensive eye examination: You might believe that your vision is perfectly fine. But it is recommended that you get your eyes regularly examined by your eye care professional so that any signs of damage or a severe eye condition can be detected before it is too late.
How Are Low Vision Aids Mitigating the Effects of Optic Nerve Damage?
If you are wondering whether the optic nerve damage is curable, the answer is No. Unfortunately, the optic nerve once damaged can never get back to its original form. It is composed of nerve fibers that cannot regenerate or heal themselves. This means that the optic nerve damage is preventable but not reversible.
Keeping in view the dire need of providing people with low vision a worthwhile and lasting solution, numerous technological inventions have been made to counter the drastic effects of acute eye conditions.
The optic nerve damage that is a result of serious eye diseases is immedicable. But as the researchers in the eyecare industry have been persistent in their search for an all-in-one solution, the low vision glasses came forth as a visual assistive device leveraging the leftover vision of the eye.
Revolutionizing the lives of people with visual impairments, low vision glasses have emerged as a game-changer. IrisVision Live is one of the most innovative and groundbreaking low-vision headsets with advanced remarkable features and software lenses for each setting. IrisVision Live improves the visual acuity of the eye by targeting the functional areas of the eye and amplifying the leftover vision.
People with optic nerve damage have blurred vision. They cannot see the sharpness of the image or the fine details of the object. This means that they have a hard time reading text from printed surfaces or a screen. IrisVision Live comes with 3 distinctive modes dedicated to assist the users in reading, namely, IrisReader with OCR, colored reading mode, and reading line mode.
Moreover, people with optic nerve damage also suffer from visual field loss. Does this mean missing out on watching your favorite team play football? Not anymore! With up to 70 degrees field and 14X magnification, the scene mode installed in the IrisVision Live headset assists in countering the visual field loss in indoor as well as outdoor spaces. The peripheral vision loss, also called the tunnel vision can be corrected using scene mode.
Lannie Dennis with optic nerve damage used to miss out watching his grandson playing his favorite sports. After using the IrisVision Live headset, this is what Lannie had to say,
“…my grandson who plays football, lacrosse and basketball, people would say there he goes, he made a touchdown. But I couldn’t see him. But now I can enjoy his games.”
Furthermore, blurred vision can also hinder your plans to go on independent shopping sprees as it is difficult to read the labels of the products sitting on a shelf in your favorite store. The bioptic mode and bubble view mode installed in the IrisVision headset allows the user to magnify the specific area of interest without losing the broader context of the surroundings.
Additionally, people with low vision also have difficulty in identifying objects in dark settings or at night. IrisVision is to the rescue once again! The flashlight feature in the headset lights up dark environments without using optimal lighting.