Pediatric Eye Diseases
Children are not just small sized adults. Their eyes have different properties and have different diseases from adults. A blind child in a developing country like India faces a lifetime of hardship. Children who are blind suffer profound social, economic and personal hardship, and so do their families.
Why is eye disease so important in childhood?
Serious eye problems in children threaten their prospects in life because of the impact on their education, personal development and future economic productivity. The impact is greater and has more severe consequences in poor parts of our country where special resources and education are lacking. Poor education and an inability to participate fully in the hard grind of daily life add greatly to the difficulty and suffering that poor vision or blindness in childhood cause.
What are the main eye diseases that affect children?
Children can experience most of the eye conditions that affect adults but, since many of those conditions are degenerative or age-related, they suffer them less frequently. Most children begin life with excellent sight but there are a variety of congenital, juvenile or inherited diseases that can cause blindness or visual disability early in life. Many of these are difficult or impossible to treat effectively.
However, there are many treatable or preventable eye diseases :
Cataract is a condition that is important to detect and treat early in childhood when it occurs. It is unusual in childhood but can be treated successfully with surgery, although the surgery is more complex than for adult cataract.
Trachoma is a disease acquired in childhood, particularly in poor countries. It usually causes disability later in life but community interventions to treat or prevent it need to include children as a primary focus.
Refractive error, particularly myopia (short-sightedness) causes considerable disability in children worldwide. Significant myopia usually appears before the age of 12. Its incidence appears to have increased worldwide over the last few decades. Effective management requires a public health approach to screen, diagnose and provide affordable spectacles to children early enough to prevent educational consequences.
Trauma is a significant cause of childhood eye disease, particularly in poor countries. Unsafe agricultural and industrial practices as well as the usual hazards of play cause many eye injuries, sometimes affecting both eyes. Unsafe practices while using fireworks and sharp objects are another main cause of trauma. When first aid and definitive treatment are not available, these injuries often have a very poor outcome.
There are two other serious eye diseases specific to childhood which cause blindness or visual disability in large numbers of people in developing countries. These are Retinopathy of Prematurity (ROP) and Nutritional Blindness (also called Xerophthalmia).
What is Retinopathy of Prematurity (ROP)?
Throughout the world, the survival of very premature infants has improved in the last few decades because of improvements in their basic care in local and regional hospitals.
When a baby is born very prematurely, the retina and its blood vessels are not fully developed. These tissues depend critically on a stable and physiological level of oxygen in the blood to develop normally.
When very premature infants are fighting for their lives, usually with oxygen supplementation, they often have a very high and highly variable level of oxygen in their blood. This helps them to survive but can seriously damage the developing blood vessels of the retina. Serious scarring in the retina, usually in both eyes and frequently causing blindness, often follows this damage.
The availability of trained staff and the skilled monitoring and treatment practices that are available in most developed countries, reduce the burden of ROP there. In most developing countries including India, however ROP remains a highly prevalent cause of childhood blindness.
Complex interventions are required to train and equip staff at these hospitals so that ROP can be prevented and minimised when it does occur. Treatment of established ROP is highly specialized, requires expensive equipment and is often unsuccessful.
Prevention is therefore the key to controlling the burden of blindness from this condition.
What is Nutritional Blindness (Xerophthalmia)?
Most of the external and internal surfaces of the body are covered with a protective layer of cells called an epithelium. The health of these cells depends critically on the availability of adequate Vitamin A in the diet. This vitamin is found in dark green leafy vegetables, some fruits, breast milk, eggs and dairy products. Children with Vitamin A deficiency are prone to many diseases, especially serious infections such as pneumonia, diarrhoea and measles.
Many poor countries in the developing world have very large populations of children either vulnerable to, or suffering from, Vitamin A deficiency.
Deficiency of Vitamin A can cause dryness of eyes and it can also cause night-blindness from reduced retinal function. If untreated the whole cornea can get damaged leading to almost permanent blindness.
Parents usually notice this when child starts bumping against things when it gets dark. Very rarely does the child says about the difficulty in seeing things in darkness.
Disastrous eye damage however usually occurs because of a combination of severe infectious illness such as measles with pre-existing Vitamin A-deficient eye disease.
This often causes severe corneal ulceration, scarring and, frequently, a melting away of the tissues of the cornea causing perforation of the eye. The damage usually occurs in both eyes and the eyes may be lost altogether.
Consult a doctor as soon as you see any abnormal sign indicating defective vision in your child. Even otherwise normal children should undergo comprehensive eye examinations at least once in two years.