Night Blindness

What is Night Blindness (Nyctalopia)?

Night blindness (or nyctalopia) is an eye condition in individuals with an underlying eye problem.

It is not a disease per se. Instead, night blindness occurs because of a retinal disease or optical issues. For example, individuals who have myopia (nearsightedness) could experience problems with night vision. 

With night blindness, individuals have trouble seeing clearly at night or in dimmed lighting, like in a movie theater or restaurant. Nyctalopia may be associated with a disease, injury, or condition that affects the rod cells (located in retinal tissue), which are responsible for vision in the dark. 

It is important to understand that night blindness does not refer to literal blindness when vision is completely lost. Night blindness implies poor sight at night or in poorly lit environments. 

Night Blindness vs. Normal Blindness

Night blindness and normal blindness are similar in that both can refer to a loss of vision. However, normal blindness may be more damaging and suggest a loss of vision that cannot be corrected with eyewear or surgery. 

Although individuals with night blindness can experience a partial loss of vision, it is not a complete loss. 

Normal blindness can often occur because of the following health conditions, including:

• Complete retinal detachment
• End-stage glaucoma (increased pressure in the eye)
• Vascular occlusion (stroke in the eye)
• Severe internal eye infection (endophthalmitis)

In the United States, the number of individuals with visual impairment or blindness is expected to reach more than 8 million by 2050. 

What Does Night Blindness Look Like?

The American Academy of Ophthalmology has put together a set of questions that help characterize night blindness. 

For example, individuals who experience night blindness may have trouble getting around the house at night, even when small night lights are turned on. 

Similarly, driving at night can appear more complicated, and there might be the fear of tripping when going outside. Individuals may also describe not recognizing people’s faces at first sight in low-light settings. 

Finally, individuals with night blindness may find that it takes the eyes more time than usual to adjust to either light coming in from the darkness or objects in a dark room. 

In the dark, the eyes are color blind: individuals mainly see black, white, and grey. Visual acuity will also decrease, and the central field of vision less clear. 

Symptoms of Night Blindness 

Because night blindness is a symptom of an underlying eye problem, symptoms can vary depending on the cause. These symptoms can range from headaches to nausea. However, other symptoms may include:

• Eye pain
• Vomiting 
• Blurry or cloudy vision
• Halos
• Light sensitivity
• Distance vision problems 

In one study, reduced vision among mature adults was demonstrated to lead to social isolation, family stress, and a higher tendency to have other health problems or experience premature death. 

What Causes Night Blindness?

Different underlying conditions or problems can lead to night blindness. However, not all of these causes are treatable. The following list describes the causes of night blindness according to its treatability. 

Treatable 

• Myopia (nearsightedness)
• Glaucoma medications (can constrict the pupil)
• Cataracts (clouding of the lens in the eye)
• Vitamin A deficiency (also referred to as a retinol deficiency)
• Diabetes (contributes to the development of cataracts and diabetic retinopathy)
• Keratoconus (a rather steeply curved cornea)

Non-treatable

• Usher syndrome (a genetic condition that leads to serious hearing loss/deafness and retinitis pigmentosa)
• Retinitis pigmentosa (an eye disease that damages the retina, primarily affecting rod cells)
• Congenital disorders (such as congenital stationary night blindness)

Congenital stationary night blindness means that the vision problems accompanying the disease are present from birth and do not often change over time. Congenital stationary night blindness seems to be more frequent in individuals of Dutch-German Mennonite descent. 

Night Blindness Treatment Options

Individuals with night blindness should consult an ophthalmology clinic and describe all symptoms to their eye doctor. Because night blindness can occur due to an underlying cause, treatment for the condition will depend on the underlying eye problem. 

For example, prescription eyeglasses or different glaucoma medications may resolve or partially address the issue of night blindness. However, in other cases, such as cataracts, surgical intervention may be necessary. 

Individuals living with a retinal disease should consult a retina specialist to determine if treatment or care support is possible. 

In the United States, an estimated 3.22 million individuals had vision impairment. 

How Can I Cure Night Blindness Naturally?

Night blindness is not treatable at home. Instead, individuals are recommended to consult an optometrist and seek medical advice for proper treatment, if available. 

However, individuals can take preventive steps to minimize the risk of night blindness, such as:

• Eating vitamin A-enriched foods. These foods can include carrots, sweet potatoes, cantaloupes, spinach, milk, and eggs. Vitamin A supplements may also be helpful, but it is best to speak first with a healthcare provider to determine if such supplements are suitable. 
• Regular eye exams. An eye care specialist could identify early-stage eye problems and provide the most appropriate treatment response, if possible. 
• Wear sunglasses.  UV exposure raises the risk of cataracts, macular degeneration (the central part of the retina called the macula deteriorates), and glaucoma. These eye problems could have an impact on vision and lead to night blindness. 
• Exercise. Working out could reduce eye pressure and lower blood glucose, which could, in turn, minimize the risk of further eye problems.