Definition
| Causes
| Risk Factors
| Symptoms
| Diagnosis
| Treatment
| Prevention
Causes
There are several common causes of night blindness:
- Lack of vitamin A, which can cause a disorder of the retina and make the eyes very dry
- Cataracts
, which are cloudy areas in the lens of the eye
-
Some forms of retinal degeneration, such as
retinitis pigmentosa
- Trouble adjusting from low levels of light to high levels of light
- Certain medications
- Birth defects
Risk Factors
A risk factor is something that increases your chance of getting a disease or condition. Some risk factors for night blindness include:
- Age: elderly people are more likely to have cataracts
- Genetics: retinitis pigmentosa
- Diet: people who don’t eat enough sources of vitamin A, such as green leafy vegetables, eggs, and whole milk products
(vitamin A deficiency is very rare in the US, but still occurs in certain less developed countries)
-
Disorders that affect the ability of the body to absorb vitamin A:
- Liver disorders
- Surgery on the pancreas or liver
- Intestinal conditions
- Bowel surgery for obesity
Symptoms
Symptoms are difficulty or inability to see in low light or darkness. While driving, this may also occur a few seconds after the bright headlights of an oncoming car have passed.
Diagnosis
A doctor will give you a medical examination to determine the cause of your night blindness. Some of the things a doctor might do are:
- Ask detailed questions about your experience of night blindness
- Test the levels of vitamin A in your blood
- Give you an eye exam
-
Ask about your medical history, including:
- Diet
- Medications
- Use of corrective lenses
- Family history of diabetes
Treatment
Depending on the reason for your night blindness, treatment will address the specific cause. Treatments generally include:
Prevention
If you experience night blindness, it is important to take safety precautions, like not driving in the evening or at night. Also, eating a diet with adequate amounts of vitamin A may help prevent night blindness.