If you are night blind, you have difficulty seeing in the dark or at dusk. In addition, your eyes have more difficulty adapting to the change from dark to light. Of course, everyone often sees less in the dark, your eyes have to get used to less light, but if your vision continues to be poor, you are probably night blind.

Contents

• When are you night blind?
• Causes of night blindness
• Can night blindness be prevented?
• The consequences of night blindness
• The treatment of night blindness

When are you night blind?

Night blindness always affects both eyes and is often a hereditary condition. Someone who is night blind sees nothing at dusk or in the dark. The eyes also have difficulty adjusting from bright light to darkness. Everyone always sees less in such a situation, but in night-blind people the eyes do not adapt and vision remains poor. The test: in a dark cinema your eyes always have to get used to the darkness, but if you can see the person next to you clearly after five minutes, you are not night blind.

Causes of night blindness

Usually hereditary predisposition plays a role, but a vitamin A deficiency can also cause night blindness. It is mainly the rods that cause problems with night blindness. The retina contains cones and rods, the cones are important in daylight and the rods in the dark or twilight. The main form of night blindness is genetic and it appears that slightly more women than men suffer from it. Other causes of night blindness can be explained by an eye disease such as cataracts. Chronic gastritis and chronic liver disease can also cause night blindness.

Can night blindness be prevented?

When vitamin A deficiency plays a role, preventing night blindness is eating foods with vitamin A. Vitamin A is found in dairy products but also in spinach, lettuce, carrots, oranges and peaches. If you think you are not getting enough vitamin A, there are always vitamin preparations. Only when night blindness is caused by this vitamin deficiency can it be prevented, in all other cases it is not possible.

The consequences of night blindness

Night blindness causes problems when driving. Even in the early twilight, vision is already reduced. In the dark, the lights of oncoming traffic are especially difficult and in rainy weather the glitter on the roads makes it even more difficult. It is not always clear where the shoulder begins, seeing traffic signs and not being able to properly estimate distances even make driving dangerous at times. According to some, driving in the dark with night blindness is just as dangerous as driving with a blood alcohol level that is too high. Driving with night blindness is difficult and if it is not absolutely necessary, it is sometimes better to stay at home.If you have to go on the road, it is better to take the well-lit roads. If you have a choice, take the quiet route. Pay particular attention to the right side of the road and try to avoid the bright lights of oncoming traffic. Adjust your speed and make sure your own car lights are in good condition.

The treatment of night blindness

Night blindness caused by a hereditary predisposition cannot be cured and becomes worse over the years. When night blindness is caused by a lack of vitamin A, a healthy diet with extra vitamin A is often sufficient. If the night blindness is caused by other underlying diseases, the disease can sometimes be treated so that the night blindness disappears or becomes less. In all cases, a check-up by an ophthalmologist is necessary.At the end of 2009, researchers from the Academic Medical Center in Amsterdam discovered the gene that causes night blindness. Nearly half of all people with night blindness have a mutated gene. The mutated gene that causes night blindness is called TRPM-1. It mainly plays a role in signal transmissions in the retina. In the case of night blindness, it is mainly the rods (but also the cones) that cannot properly transmit their signals to the optic nerve. At present, this can especially simplify the diagnosis of night blindness. A possible therapy that would result from this discovery is not yet expected.