Blind and blindness refer to a wide range of conditions involving the impairment of vision. A blind person is unable to see and is under a state of being sightless. It is presently used to describe a severe decline in the vision of one or both eyes with the maintenance of residual vision.
Vision impairment or low vision means that even with the use of eyeglasses, contact lenses, or surgery, you will not see well. It can range from mild to severe. Blindness or vision impairment has various causes. Approximately 80% of blindness happens to people over the age of 50 years.
Other types of blindness
There are several types of blindness. Color blindness is the inability of a person to identify differences in shades of color. They are specifically blind to green and red shades that others can easily distinguish. This condition is often inherited and primarily affects around 8% of males and less than 1% of women. People with color blindness have normal vision and can function visually well. This type is not real blindness.
Similarly, night blindness is a condition wherein a person has difficulty seeing under situations of reduced illumination. This case can be genetic or acquired. Most people with night blindness function well in normal lighting conditions; thus, this is not a case of real blindness.
Additionally, some people experience temporary loss of vision after exposure to large amounts of ultraviolet light. This is called snow blindness. The cells of the cornea swell and cause temporary blindness, but even in severe cases, the person can still see movement and shapes.
Symptoms of Blindness
People who are blind are visually impaired. They also have difficulty in seeing things. Those with similar loss of vision may have very different responses to blindness symptoms. Those who are born blind have less adjustment to make than those who lost their sight later in life. At present, there is a support system available for people who are blind, and their psychological makeup also adjusts to the symptoms of lack of sight. On the other hand, people who lose their sight suddenly, than those who gradually lose sight over the years may have more difficulty in adjusting to their loss of vision.
Depending on the underlying cause of blindness, symptoms may vary widely. A blind person may have no visible signs of abnormalities when at rest. But when the condition is a result of an infection of the cornea, it may appear white or grayish instead of transparent. If the blindness is due to cataract, the pupil appears white instead of the usual black.
More so, depending on the degree of the condition, the person may show signs of vision loss when trying to move around. Some blind people have already learned to look at the person they are speaking with; thus, it is not evident that they are sightless.
People who are entirely blind do not see anything. Those who are partially blind may have the following symptoms:
- Tunnel vision
- Poor night vision
- Cloudy vision
- Seeing only shadows
- Inability to see shapes
For infants, the visual system starts to develop in the womb. Their vision is not fully formed until two years of age. At around 6 to 8 weeks of age, an infant can already fix their gaze and follow movements. At approximately four months, their eyes are correctly aligned. Some symptoms of visual impairment in young children include:
- Poor focus
- Constant rubbing of the eyes
- Extremely sensitivity to light
- Chronic tearing of the eyes
- Persistent redness of the eyes
- The whiteness of the pupils
- Abnormal eye alignment after six months of age
- Poor visual tracking
Causes of Blindness
The causes of blindness differ widely in various conditions. According to some socioeconomic studies, developed nations have more cases of blindness caused by ocular complications. It includes macular degeneration, traumatic injuries, diabetes complications, and glaucoma. In third-world countries, the principal causes of visual impairment include cataracts, injuries, infections, glaucoma, and inability to obtain eyeglasses.
Infectious diseases that cause blindness in underdeveloped nations include leprosy, trachoma, and onchocerciasis. Similarly, the most common infectious cause of blindness in developed areas is herpes simplex. Other causes of blindness include the following:
- Glaucoma – various eye conditions that lead to damage to the optic nerve, thus visual information from the eyes to the brain is affected
- Macular degeneration – usually affects the elderly. It destroys parts of the eyes that allow you to see details.
- Lazy eye – makes it difficult to see small details. If not addressed early, this can lead to loss of sight
- Cataracts – this condition leads to a cloudy view and are more common in older people
- Optic Neuritis – an inflammation that may lead to temporary or permanent loss of vision
- Retinitis Pigmentosa – damages the retina and in rare cases, it can lead to permanent blindness
- Tumors that affect the optic nerve or retina
If you have diabetes or had a stroke, blindness is also a potential complication. The small veins in your eyes may burst and damage your vision due to high sugar-levels or high-cholesterol levels. Other causes include congenital disabilities, injuries, and complications to eye surgery.
Diagnosis and Treatment
There are various procedures to diagnose blindness. Each eye is tested individually by measuring visual acuity, visual field, and peripheral vision. Some people are blind in one eye or are blind in both eyes. Your ophthalmologist will gather historical information about your condition to find the real cause of your blindness. Poor vision that occurs suddenly may have different causes than blindness that is chronic or progressive. Likewise, temporary blindness also differs in causes than that of permanent vision loss.
Treatment for blindness or visual impairment will depend upon the cause of the condition. In underdeveloped nations, people with poor eyesight due to refractive error may alleviate the problem with the use of glasses. Additionally, dietary changes can help address blindness caused by nutritional deficiencies.
Presently, there are millions of people around the world who became blind due to cataracts. In many of these patients, surgery can restore their eyesight. Medications may also treat blindness due to infectious causes and inflammation. Also, people who have lost their vision due to corneal scarring may benefit and restore their vision through a corneal transplant.
For complete blindness wherein vision can no longer be restored, there are ways to approach life in a new way. Patients should learn new skills like using Braille, having a guide dog and a walking stick, organizing home they are safe and will find things easier.
What are the Normal Conditions?
The eyes are essential in keeping things healthy. You rely on your eyes to see things and make sense of the world. Eye diseases can lead to vision loss; thus, it is vital for you to know the symptoms and have any issues checked and treated as soon as possible. More so, it is equally important to keep your eyes healthy, along with keeping your body healthy. Some things that you can do to keep your eyes healthy include the following:
- Eating a healthy and balanced diet and include vitamin-rich foods that aid in eye health.
- Maintain a healthy weight to avoid diseases that have blindness as its complications
- Exercise regularly to prevent diabetes, high cholesterol, and high blood pressure. These conditions can cause eye problems and vision loss.
- Wear protective glasses and avoid too much sun exposure. Use sunglasses to protect your eyes from the sun and prevent injuries at work.
- Avoid smoking as it increases the risk of developing age-related vision impairment.
- Know your risks and your family’s medical history.
- Rest your eyes and reduce eye strain by looking away from your computer every 20 minutes.
What are the Risk Factors?
Blindness can be prevented. If treatment is given in the early stages of vision impairment, a person can save his or her sight. One of the primary risk factors for blindness is the unavailability of ready access to sophisticated medical care. Most underdeveloped countries have many people who have lost their vision due to causes that are treatable and preventable.
Similarly, the risk for blindness is higher if you have the following conditions:
- High blood pressure/Stroke
- Eye disease such as glaucoma
- Eye surgeries
- Dangerous work environment
Other risk factors that may lead to vision impairment include advancing age, poor hygiene, smoking, inadequate prenatal care, family history, medical conditions such as cerebrovascular and cardiovascular diseases.
When to Call Your Doctor?
As we grow older, changes in vision are expected. However, for sudden vision impairment or changes, it is a sign that there is something wrong. You need to schedule an appointment with your eye doctor. If you notice sudden changes such as blind spots, blurriness, dimness of vision, and halo around lights, you need to have your eyes checked.
Over time, these symptoms can worsen, and if untreated, it can lead to permanent damage to your eyes. Vision changes may indicate various eye conditions, including glaucoma, cataracts, retinal detachment, macular degeneration, dry eyes, and diabetic retinopathy.
Regular eye examinations can help prevent eye problems and address symptoms before they become severe and cause permanent blindness.