Night blindness (nyctalopia) affects vision clarity in low light conditions and can significantly impact performance of daily activities.
Night blindness, despite its name, does not only affect night vision, but also the ability to see in dimly lit areas, such as a restaurant or theatre.
If you are finding it difficult to drive at night, especially with the intense glare from the headlights of oncoming traffic, or are having trouble recognizing faces and objects in low light conditions, you may be suffering from night blindness.
Night blindness is not an eye condition in and of itself, but rather a symptom of another underlying condition— generally stemming from an eye disease, severe or worsening myopia, or a vitamin A deficiency.
How is night blindness diagnosed?
Night blindness can only be diagnosed during a comprehensive eye exam.
Your eye doctor will ask you questions about your medical history and conduct a series of tests to identify signs of an ocular disease or vision condition.
Many eye doctors use the Pelli-Robson contrast sensitivity chart to detect signs of night blindness. This chart contains numerous rows of letters in different shades of grey, on a white background.
During this test, you will be asked to identify the letters on the chart. As your eyes move down the chart, the letters will appear in lighter shades of grey, as the contrast to the white background is reduced.
Some eye doctors may also require a blood test to determine your vitamin A and glucose levels.
Vitamin A deficiency can directly cause night blindness, while abnormal glucose levels can lead to eye diseases that can affect your retinal health and vision— and many times lead to night blindness.
How is night blindness treated?
Since night blindness can be caused by a number of underlying conditions, treatments can vary from patient to patient.
Night blindness caused by cataracts can be treated by removing the cataracts themselves. When cataracts begin to affect your performance of daily activities, it may be time to consider cataract surgery.
Cataract surgery involves replacing your eye’s cloudy lens with a new and clear artificial lens. Not only will this improve your vision for daily activities, but your vision for nighttime activities as well.
However, certain glaucoma medications called miotics, cause the pupils to become smaller in size, which can also result in reduced night vision.
Unfortunately, scientists have yet to discover a treatment for retinitis pigmentosa, as it is a genetic condition and does not respond to corrective lenses or retinal surgery.
If night blindness is caused by retinitis pigmentosa, or any other genetic condition, such as Usher’s Syndrome, speak with your eye doctor about ways to cope with decreased night vision— specifically, how to reduce your risk of accidents and improve your quality of life.
Night blindness that is caused by nearsightedness and/or astigmatism can be treated with corrective lenses, such as eyeglasses or contact lenses that contain an updated and appropriate optical prescription.
Refractive laser surgery
If you are experiencing night blindness following a refractive eye surgery, such as LASIK or PRK, speak with your eye doctor about adding an anti-reflective coating to your eyeglasses to reduce glare and halos.
Vitamin A deficiency is a common cause of night blindness, and can be treated with vitamin A supplements. As your vitamin A levels regulate, your night vision should return to normal.
If you have diabetes and are experiencing night vision difficulties, it is important to see your eye doctor to determine if diabetic retinopathy is the cause. Treating diabetic retinopathy with anti-VEGF medication, laser treatments, or surgery and controlling your diabetes can help to relieve your night vision problems.
How can I prevent night blindness?
Night blindness caused by genetic conditions cannot be prevented. However, some eye diseases and conditions that affect night vision can be prevented by making some essential lifestyle adjustments.
Changing some of these lifestyle habits can decrease your risk of night blindness:
Eat foods rich in vitamin A
Increasing your consumption of foods rich in vitamin A can help delay the onset of cataracts, and may also act to protect your retinal health.
Foods that are rich in vitamin A are typically an orange-color and include:
- Sweet potatoes
- Butternut squash
Vitamin A can also be found in:
- Collard greens
Schedule regular eye exams
Regular comprehensive eye exams are a critical tool for detecting signs of eye disease, even before symptoms are noticed.
During a comprehensive eye exam, your eye doctor will use specific diagnostic tools and imaging techniques to examine your retina, along with all of your inner ocular structures, to detect any signs of damage.
Early detection of an eye disease can increase your chance of a positive treatment outcome, and reduce your risk of night blindness.
Maintain healthy glucose levels
If you are pre-diabetic, have insulin resistance, or have been diagnosed with diabetes, it is crucial that you follow your doctor’s advice to keep your glucose levels under control.
Take your medication as prescribed, and make lifestyle and dietary changes to maintain optimal health and prevent eye conditions that can lead to night blindness.
Wear sunglasses outdoors
Sunglasses are not only fashionable and stylish, they also protect your eyes. Prolonged exposure to the sun’s harmful UV rays can damage the proteins in your eye’s lens and increase your risk of cataracts, glaucoma and macular degeneration.
When shopping for a new pair of shades, be sure that they:
- Block out 99% to 100% of UVA and UVB rays
- Filter out 75% to 90% of visible blue light
- Are large enough to protect your eyes from all sides
Get regular exercise
Studies have shown that moderate exercise at least three times per week, may actually reduce your risk of developing many ocular conditions by lowering eye pressure and blood glucose levels.
Create a regular exercise routine to help you maintain a healthy lifestyle— protecting your eyes and reducing your risk of night blindness.
Caution: Always consult with your doctor before beginning any new exercise program.
Update your optical prescription
If you have myopia, or are experiencing vision changes that affect your ability to see distant objects clearly, be sure to schedule an appointment with your eye doctor.
It is important to ensure that you are wearing the correct optical prescription, as a prescription that is too weak can cause blurry vision both during the day and at night.
Safety precautions while coping with night blindness
If you are experiencing night blindness, or any degree of decreased night vision, it is important to protect yourself from accidents, and keep others safe as well.
- Avoid driving at night.
- Ask a friend, family member, or taxi service to help you with your nighttime travel needs.
- Wear sunglasses and a wide brimmed hat to help reduce glare in a brightly lit environment.
If you are experiencing night blindness, or any degree of decreased night vision, know that you are not alone.
With proper treatment and management of the underlying conditions causing your night vision difficulties, you can reduce your symptoms and enjoy increased independence for many of your daily activities.