Night Blindness: What Is It Exactly?
If you have trouble seeing in relatively low light situations, then you may be suffering from night blindness or nyctalopia. Night blindness is a symptom of several different conditions. Its onset generally warrants the scheduling of an eye exam, as many of the conditions that cause night blindness are treatable and some can be quite serious.
Read on for a brief examination of the symptoms, possible underlying medical issues, diagnosis and treatment of the condition commonly known as “night blindness.”
History of Night Blindness
The first medical description of night blindness is attributed to first century Roman encyclopaedist, Aulus Cornelius Celsus. He described the condition as a weakness of the eyes present only at night in people that could see perfectly well in daylight. He recommended a folk remedy, the eating of male goat’s liver, to treat the condition.
The condition, also known as moonblink, has been historically attributed in some cultures to sleeping in moonlight, and a variety of other possible causes.
Symptoms of Night Blindness
Night blindness can be present in some patients as early as birth, and it can be caused by a variety of things (see below). But it is generally described as insufficient adaptation to low light situations, or relative darkness. The eyes need at least some light to function, even in healthy unaffected people. Sufferers of night blindness report having trouble seeing objects that unaffected people can see easily.
They also report seeing halos of light around bright objects, and typically have trouble driving at night. Patients suffering from night blindness also report needing extra time for their eyes to adjust to changes in brightness.
Diagnosis and Treatment for Night Blindness
Night blindness can be a symptom of several different conditions, ranging from over-exposure to the sun to chronic disease to vitamin deficiency. One of the most common causes of night blindness is cataract. As cataracts develop over a lifetime, they begin to slowly cloud the lens of the eye, making it harder to see in all conditions. But cataracts often affect a person’s night vision first.
The distortion of light entering the lens of the eye can produce halos around lights, making it more difficult to see at night, especially while driving.
Another condition that may lead to night blindness is retinitis pigmentosa. Retinitis pigmentosa is relatively rare genetic condition that mostly affects people younger than thirty. Difficulty seeing in low light conditions is often the first symptom of this problem. Patients report varying degrees of sight loss, but most retain at least some vision.
Causes of Night Blindness
Night blindness may be caused by vitamin A or zinc deficiency. Zinc and vitamin A work together in the eye to help maintain the health of the retina. Ensure that you get enough vitamin A and zinc either from natural dietary sources, or from supplements. Green and yellow leafy vegetables are good sources of vitamin A, as are carrots. Beef, beans, nuts, and poultry are good sources of zinc.
Type two diabetes is another common cause of night blindness, and warrants immediate treatment by a physician for its potential lethalness. The retina of the eye can be damaged over the years by issues with excessive blood sugar.
Depending on the underlying condition causing night blindness, treatment can range from cataract surgery, to supplementation, to diet and exercise. It is important that you schedule an eye examination and potential follow up appointments with your general practitioner to identify and address the causes of your symptoms.
[Photo Via: RMS]