According to the Cleveland Clinic, night blindness, or nyctalopia, is the inability to see well in poor light or at night. Untreated nearsightedness may be a possible cause as night blindness generally is a symptom of an underlying condition. The National Library of Medicine says those with night blindness are usually unable to see the stars on a clear night.
Symptoms
As the name implies, night blindness is characterized by the inability to see clearly in the night. Difficulty seeing in or adjusting to low light is another characteristic as discussed by the Cleveland Clinic. Night blindness itself is usually a symptom of an underlying condition. If any problems adjusting to light or if blindness is present, a discussion with a medical professional is warranted.
Causes
As you age, your eyes may take longer to dilate and may take longer to adjust to low light, as discussed by the Merck Manual. Other causes may be birth defects in the eyes and cataracts. A deficiency of vitamin A, which is found in orange and yellow vegetables, may also be an underlying cause. Retinitis pigmentosa, a disease in which the retina is progressively damaged, may also be a cause of night blindness.
Diagnosis
Diagnosis for night blindness can be quite thorough. According to the Cleveland Clinic, a doctor will perform an extensive eye exam, and may possibly order any number of specialized exams, including a slit lamp exam or ophthalmoscopy. The doctor will want to know when the condition began, and if it was a gradual or sudden process. Diet, medications and any recent injuries will also be examined.
Treatment
Night blindness may be curable, depending on the underlying cause, as discussed by the National Institutes of Health (NIH). The eye doctor may change any existing eyeglass prescription or change any medications. If the night blindness is caused by cataracts, surgery is usually required to remove them. Vitamin A supplementation will be initiated if a deficiency is present.
Preventing Problems
If night blindness is present, some precautions can be taken to ensure your safety until the situation is taken care of. Improving lighting around the house, especially around steps and in the kitchen, will help prevent falls and obstacles. Regular eye exams will help detect any cataracts or underlying conditions.
