Childhood blindness

Vitamin A deficiency is most common in developing countries where many kids experience malnourishment. This vitamin deficiency blinds hundreds of thousands of kids each year, and is a preventable cause of childhood blindness. Since vitamin A is required for rhodopsin, the photosensitive pigment in the retinol rods, its deficiency can lead to night blindness.[8]

Since 2010, globally 85% of children have been vaccinated for measles significantly reducing the number of measles cases each year. Children who have a vitamin A deficiency and measles infection can develop corneal ulcerations and keratomalacia due to immunosuppression caused by the vitamin deficiency.[8]

Newborn conjunctivitis is present at the time of birth and presents within the first 28 days of life as a severe conjunctival infection with purulent discharge. This increases the risk of corneal ulcerations and perforations that can lead to blindness. The common organisms that lead to this diagnosis include Neisseria gonorrhoea and Chlamydia trachomatis. Infected pregnant women and their partners should be treated to avoid infection of the newborn, and newborns presenting with conjunctivitis should be treated with hourly topical antibiotic drops (gentamicin). [8]

Retinopathy of Prematurity (ROP) is classified by the abnormal growth of blood vessels in the retina, a process called retinal neovascularization.[9] These blood vessels may bleed or grow in the wrong direction. Bleeding can lead to the formation of scar tissue which can cause blurred vision and vision loss. If the vessels grow too far in the wrong direction, they can pull the retina away from the back of the eye – this is called retinal detachment. Retinal detachment is a medical emergency that can cause permanent blindness and thus requires urgent intervention.[10]

Babies who are born prematurely (formally defined as 37 weeks of gestational age or earlier) are at higher risk of developing retinopathy of prematurity. The earlier a preterm baby is born, the greater the baby's risk of developing ROP. Blood vessels in the eye typically finish development by the time of birth. Therefore, a baby who is born early is exposed to various stimuli (oxygen, lights, temperature, etc.) that may influence how the blood vessels of the eye develop. Additional risk factors for ROP include low birth weight (3 pounds or less) and giving the baby extra oxygen following birth. If preterm infants are experiencing other health problems like anemia, vitamin E deficiency, and/or breathing problems, they are at increased risk of developing ROP.[11]

Vitamin A deficiency is a leading cause of preventable childhood blindness, particularly in developing countries. Vitamin A deficiency is defined as a serum (blood) concentration of less than 0.70 µmol/L while a severe deficiency is defined as less than 0.35 µmol/L, per the Centers of Disease Control National Health and Nutrition Examination Survey.[18] Vitamin A is supplied through the diet, and a deficiency often results from poor dietary intake of Vitamin A-rich foods.[19] Low dietary levels of Vitamin A can be worsened by infections that cause inflammation in the gastrointestinal tract, which prevent the body from fully absorbing Vitamin A available within digested food. Children in the United States have a recommended Vitamin A dietary allowance of at least 300 micrograms/day.[19] Good sources of Vitamin A include vegetables, such as carrots, papaya, and pumpkin.[20] Animal products, such as fish oils, as well as dairy products (milk, cheese, and yogurt) are also sources of Vitamin A.[20]

Retinopathy of prematurity (ROP) is a cause of childhood blindness that can occur around the time of birth. Generally, measures taken to avoid preterm birth are also effective at preventing ROP. Babies delivered preterm, defined at or before 37 weeks of gestation, have incomplete development of the blood vessels supplying the retina.[21] At birth, increased exposure to oxygen from the environment and from medical interventions (such as a high flow nasal cannula) causes damage to retinal blood vessels and stunts their growth. Prevention of ROP in preterm babies involves careful monitoring of oxygen delivery to avoid excess exposure.[22] Neonatal ocular exams can help detect ROP.[23]

Braille is a universal way to learn how to read and write, for the blind.[26] A refreshable braille display is an assistive learning device that can help such children in school.[27] Schools for the blind are a form of management, however the limitations of using studies done in such schools has been recognized. Children that are enrolled presently usually developed blindness 5 or more years prior to enrollment, consequently not reflecting current possible causes.[28] About 66% of children with visual impairment also have one other disability (comorbidity), be it, intellectual disabilities, cerebral palsy, or hearing loss.[29] Eye care/screening for children within primary health care is important, as catching ocular disease issues can lead to better outcomes overall.[30]