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 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:
In the United States, the number of individuals with visual impairment or blindness is expected to reach more than 8 million by 2050.
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.
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:
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.
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.
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.
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.
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:
Boyd, Kierstan. “Shedding Light on Night Blindness.” American Academy of Ophthalmology, 18 Mar. 2017, www.aao.org/eye-health/news/shedding-light-on-night-blindness.
“Blindness and Vision Loss: MedlinePlus Medical Encyclopedia.” MedlinePlus, U.S. National Library of Medicine, medlineplus.gov/ency/article/003040.htm#:~:text=Blindness%20is%20a%20lack%20of,blindness%22%20mean%20complete%20blindness.
“Burden of Vision Loss.” Centers for Disease Control and Prevention, Centers for Disease Control and Prevention, 12 June 2020, www.cdc.gov/visionhealth/risk/burden.htm.
“Night Blindness (Nyctalopia) Care and Treatment.” Cleveland Clinic, my.clevelandclinic.org/health/symptoms/10118-night-blindness-nyctalopia/care-and-treatment.
“X-Linked Congenital Stationary Night Blindness: MedlinePlus Genetics.” MedlinePlus, U.S. National Library of Medicine, 18 Aug. 2020, medlineplus.gov/genetics/condition/x-linked-congenital-stationary-night-blindness/.