Night blindness, or what is also called nyctalopia, is a decrease in vision that a person experiences at dusk or when lighting dims, due to damage to the function of stem cells in the retina. The eye as a sense of sight was created to be able to adjust to bright or dark conditions in a short time. In night blindness, there is a decrease in the ability of the eye to adapt or adjust vision with dim lighting. This can occur if there is degeneration (decreased function) in stem cells, namely the eye sensory nerve cells that work in dim lighting. Night blindness can also occur if there is a lack of Rhodopsin pigment in these stem cells, it could be due to heredity, it could also be due to a lack of vitamin A.
Not all conditions for night blindness can be treated. This depends on the severity or damage experienced by the sufferer.
The cause of night blindness
The main cause of night blindness or nyctalopia is damage to the stem cells in the retina. This condition is usually triggered by health problems, such as:
- Nearsightedness or the inability of the eye to see distant objects.
- Cataract. This condition is common in people who have entered old age, or it can be in people with diabetes and causes the eye lens to look blurry or cloudy.
- Vitamin A. Deficiency One of the causes of this condition is cystic fibrosis, which causes the digestive tract to become blocked by thick, sticky mucus so that the body is unable to absorb fiber and vitamins.
- Retinitis pigmentosa. In the condition of pigment buildup in the retina and cause narrowing of the field of view known as tunnel vision. This condition cannot be treated.
- Glaucoma. Conditions that cause damage to the optic nerve due to the pressure inside the eye and can worsen over time.
- Keratoconus. Corneal thinning is caused by low levels of antioxidants in the cornea, resulting in damage to collagen tissue and prominent cornea. Besides genetic factors, this condition can also be caused by exposure to air pollution.
- Usher's syndrome. In addition to influencing the ability to see, this condition can interfere with the hearing of the sufferer.
Symptoms of Night blindness
As mentioned above, night blindness sufferers will find it difficult to see at night, and difficult to adapt when there is a transition from light to dark. Besides being able to disrupt daily activities, this condition can also endanger the sufferers' personal safety, especially when driving or going out at night.
Night blindness diagnosis
Given the symptoms of night-blindness are not much different from other eye diseases, the doctor will do a physical examination and ask about the severity of symptoms experienced, the time of appearance of symptoms, activities that are usually done, the use of eyepiece, or drugs consumed. In addition, genetic factors will also be taken into consideration when making a diagnosis.
To ensure suspicion that the patient is suffering from night blindness, additional eye examinations can be performed, including:
- Color test.
- Eye refraction test.
- Check with a slit lamp.
- Test the pupillary reflex for light.
- Retinal examination.
- Visual acuity examination.
- Electroretinogram (ERG).
- Field of view inspection.
In addition, blood tests may also be performed to check glucose and vitamin A levels in the blood.
Treatment for night blindness
Treatment of night blindness or nyctalopia will be adjusted to the severity and the causative factors. Treatment of mild night blindness, for example by the use of contact lenses or glasses, can be an option for sufferers.
If the cause is vitamin A deficiency, the treatment is to arrange a meal menu and administration of vitamin A supplements will be given.
If the patient has cataracts, surgery can be done to replace the opaque eye lens with an artificial clear eye lens. The condition of night blindness caused by genetic factors is generally not treatable. In this case, the patient will be advised not to drive or carry out activities without adequate lighting at night.
Night blindness prevention
Night blindness cannot be completely prevented, especially if it is based on genetic factors. However, there are several things that can be done to reduce the severity of the condition, such as:
- Eating foods with high antioxidant and mineral content.
- Monitor blood sugar levels regularly.
- Use sunglasses when you move in the heat to avoid glare.
Vitamin A deficiency is often the main reason for night blindness to occur. To avoid this, some of the following food intakes can be selected:
- Sweet potato
- Carrot
- Pumpkin
- Mango
- Spinach
- Mustard greens
- Milk
- Egg