What Causes Night Blindness?

Night blindness occurs when a person experiences reduced night vision. It typically causes impaired vision in the darkness and does not impact vision in the light. This condition, unless accompanied by other eye disorders, is not true blindness. Even at nighttime, the eye is not ‘blind’ because the rods of the photoreceptor cells, which are needed for dim light, are not functioning correctly. However, night blindness symptoms are quite disruptive in everyday (and night) life.

Night Blindness Symptoms

Night blindness symptoms can vary on an individual basis for each patient. Symptoms include weak vision in dim light, difficulty seeing during night driving, and slow vision adaption between bright and dim light conditions. For a more adequate diagnosis of any signs or symptoms and whether they are indeed night blindness symptoms, consult your doctor.

What Causes Night Blindness?

To identify the causes of night blindness, it is important to understand the function of rods and cones in your eye. The rods and cones in your eye are the photoreceptors that take in light and pass information through the optic nerve to your brain for interpretation. The rods are responsible for vision in dim light and if these cells are impaired, poor or no night vision occurs.

Night blindness is a genetic defect-related condition associated with failure of rods and cones to function correctly. When this occurs, the rods in your retina do not respond to the light and you cannot see in dim light conditions. Poor vision, especially at night, is present in many vision conditions. If you have difficulty seeing at night, consult your doctor for an accurate diagnosis.

Common conditions associated with night blindness include:

 Diabetes. Night blindness is an early indicator of damage due diabetes.
 Cataracts. Early signs of cataracts are poor night vision with halos around lights, glare and blurry vision.
 Myopia. Night blindness can be a sign of untreated myopia.
 Vitamin A Deficiency. Night blindness is one of the first signs of vitamin A deficiency, which is commonly associated with malnutrition. The vitamin deficiency often develops in malnourished children who are too young to recognize a problem with their night vision.

Other conditions that may result in poor night vision include: celiac disease, cystic fibrosis, bile duct obstruction, cirrhosis of the liver, lasik eye surgery, cataracts, diabetic retinopathy, glaucoma, macular degeneration, retinal detachment, and vitreous detachment.

Am I at Risk of Night Blindness?

 Age. Older adults have a greater risk of developing night blindness due to cataracts than children or young adults.
 Malnutrition. Vitamin A plays a role in transforming nerve impulses into images in the retina. The retina is a light-sensitive area in the back of your eye. Malnutrition and absorption of vitamin A can lead to night blindness.
 High Blood Glucose. People who have high blood glucose or diabetes have a higher risk of developing eye diseases, such as cataracts.

How to Live with Night Blindness?

To diagnose night blindness, your eye doctor will take a detailed medical history and examine your eyes to diagnose night blindness. You may also need to give a blood sample to measure your vitamin A and glucose levels.

Night blindness caused by nearsightness, cataracts or vitamin A deficiency is treatable. Corrective lenses, such as eyeglasses or contacts, can improve nearsighted vision during day and at night.

If you are diagnosed with night blindness, here are a few tips to help you lead a healthier life.

• Increase your visibility. Clean your headlights.
• Slow down. Give yourself more time to react to any unexpected hazards.
• Wear sunglasses outside. Amber and grey lenses ae the most effective protection against UVA/UVB and blue light.
• Get prescription glasses for driving at night. See your doctor to determine if they would be helpful.
• Get non-glare glasses. You can get non-glare glasses with a coating that have an anti-reflective coating.
• Drive during daytime. Even good lighting conditions at night can be troublesome to someone with night blindness.

If your night blindness is associated with vitamin A deficiency, your doctor might recommend vitamin supplements. However, if your condition is a result of cataracts, your doctor might recommend surgery to replace your cloudy lens with a clear, artificial lens.

How Can I Prevent Night Blindness?

You can’t prevent night blindness associated with birth defects or genetic conditions. You can, however, properly monitor your blood sugar levels and eat a balanced diet to make night blindness less likely.

Eat foods rich in antioxidant vitamins and minerals, which may also help prevent cataracts. Also choose foods that contain high levels of vitamin A to reduce your risk of night blindness. Excellent sources of vitamin A include cantaloupes, sweet potatoes, carrots, pumpkins, butternut squash, mangoes, spinach, collard greens, milk, and eggs.

For help or questions regarding problems with your eyesight please do not hesitate to contact Advanced Eye Medical today to help you clear up your concerns and your vision.