There are many different eye conditions and diseases that can affect a child’s vision. Early detection and treatment are important to avoid lifelong visual impairments. If you or your pediatrician suspects an eye problem or if your child fails a vision screening at school, then consult a pediatric ophthalmologist for further evaluation and diagnosis. By finding and treating problems early, healthy vision can be restored. Sight of the child is most important for good education and social growth.
Eye disorders and eye diseases
Some of the common eye disorders and eye diseases found in children are:
1. Refractive Errors :
Refractive errors occur when a light forming image of an object does not focus clearly on the retina. It can cause headache, blurred vision, strain, tiredness, and cross eyes. If correction of these refractive errors is not done at an early stage, a child can be left with permanently blurred vision in adulthood called amblyopia. Refractive errors are further differentiated as
a) Myopia (or nearsightedness) :
When light focuses in front of the retina due to a long eyeball or high focusing power of the lens or cornea, distant objects appear blurry. These objects become clearer only when they get closer to the eye. This eye disorder is known as Myopia and may either be inherited or associated with premature birth and can occur at any age. Myopia usually progresses yearly and stabilizes by the late teens to early twenties. Diverging or negative (-) power glasses focus the light rays on the retina and improve vision. Contact lenses may be used instead of glasses if children are old enough to take proper care of them. At the appropriate age, laser surgery may be an alternative if the eyes are not still growing or changing.
b) Hyperopia (farsightedness) :
Hyperopia is the refractive error of the eye where the image of a distant object becomes focused behind the retina. This condition arises either because the eyeball axis becomes too short or the refractive power of the eye becomes too weak thereby making close objects appear out of focus. This leads to eye strain, headaches, or fatigue. The symptoms of Hyperopia in children are Squinting, continuous rubbing of the eyes, lack of interest in school and difficulty in reading. Treatment of Hyperopia includes correction with converging or plus (+) power glasses, particularly when associated with crossed eyes (accommodative esotropia)
c) Astigmatism :
This is an eye condition where the curvature of the cornea is abnormal leading to two focal points in two different locations. This makes objects both up close and at a distance appear blurry. Astigmatisms cause eye strain and may be combined with nearsightedness or farsightedness. Astigmatism can start either in childhood or in adulthood and the symptoms include headache, eye strain and fatigue. Children with Astigmatism suffer from continuous eye rubbing, lack of interest in school and difficulty in reading. Treatment includes prescription cylindrical power glasses to help kids with astigmatism make a more crisp, clear visual connection with the brain.
2. Amblyopia (Lazy Eye) :
Lazy eye (amblyopia) is reduced vision in one eye caused by abnormal visual development early in life. The weaker or lazy eye often wanders inward or outward. Amblyopia generally develops from birth up to age 8 years. It is the leading cause of decreased vision among children. The weaker eye receives fewer visual signals. Eventually, the eyes’ ability to work together decreases, and the brain suppresses or ignores input from the weaker eye. Rarely, lazy eye affects both eyes. It is important to diagnose and treat amblyopia as early as possible. Otherwise, a child with amblyopia will not develop normal, healthy vision.
Amblyopia can be caused by
- Refractive errors: Undiagnosed or uncorrected refractive errors can cause Amblyopia. Unequal vision due to a bad refractive error in one eye can “turn off” that eye thereby hampering the normal development of vision. This can be difficult to tell since the child’s vision seems fine when using both eyes.
- Strabismus: The most common cause of lazy eye is an imbalance in the muscles that position the eyes. To avoid seeing double, the child’s brain may ignore the image from the eye that is not focused straight ahead and prevents them from working together.
- Cloudiness:The development of white opacities in any part of the eye like cataract can prevent formation of clear images in that eye, leading to abnormal vision and amblyopia. Deprivation amblyopia in infancy requires urgent treatment to prevent permanent vision loss. It is often the most severe type of amblyopia.
- Droopy eyes: When eyelids droop over the eye, this will block light rays from entering the eye thereby causing deprivation amblyopia.
Poor vision in one eye does not always mean a child has amblyopia. In some cases, wearing glasses to correct a refractive error in one eye can improve vision. Amblyopia is usually corrected by making the child use their weaker eye. This is often done by putting a patch over the child’s stronger eye and making the child do activities with weaker eye for a few hours every day. In some cases, eye drops can be used to blur vision in the stronger eye. Or the child may wear eyeglasses with a hazy lens that blurs vision in that eye.
It generally takes several weeks to several years to strengthen vision in the weaker eye. This therapy needs to be continued for a few years to avoid re-development of amblyopia.
3. Strabismus or Crossed eyes :
This is an eye disorder where both eyes look in different directions at the same time. Misalignment of eyes at times can shift from one eye to another.
For our eyes to focus on a single object, six eye muscles work together. One muscle is involved in moving the eyes to right, another muscle is used to move the eye to the left, and there are four eye muscles that are involved in the movement of the eyes turn up, down, in and out. These muscles are controlled by the brain. Strabismus is a condition which is usually found in people with poor control of the eye muscle and is a common eye condition found in children.
Strabismus can be caused by any eye injury or as a genetic inheritance. While Strabismus is not related to any other medical conditions, children with this eye disorder may suffer from disorders such as
- Cerebral palsy
- Down syndrome
- Brain tumor
- Extra fluid in the brain
For children affected with Strabismus, the depth perception of the vision gets affected. In the case of adults who develop Strabismus after childhood, they suffer from double vision.Types of Strabismus :
The three common forms of strabismus are:
- Infantile Esotropia – a condition where one or both eyes of a baby or young child turn inward toward the nose.
- Accommodative Esotropia – the most commonly found eye disorder in 2-year-oldsThis is a condition where only one eye may turn inward (towards the nose) while focusing on any object.
- Exotropia – Also called wall-eyed, this is a condition where one or both eyes turn out while focusing on objects far away.
If detected early in life, this eye disorder can be treated or reversed. However, if this condition is left untreated, this can lead to Amblyopia.
Depending on the child’s age, and alignment, the treatment differs.
- Babies and young children with inward esotropia are prescribed surgery or glasses.
- Surgery of the eye muscles are done to align the eyes to ensure good vision. Strabismus surgery is generally conducted as an outpatient treatment and is a safe and effective way to treat eye misalignment.
- Children above 2 years are prescribed special eye-glasses to improve the focus and straighten the eyes. Prisms are also used to help these children with Esotropia focus well.
- Patching or blurring of the stronger eye is prescribed as a treatment to ensure continuous use of the weaker eye to enable the weaker eye to strengthen over a period.
Conjunctivitis (Pink Eye) :
Pinkeye (or conjunctivitis) is inflammation of the white part of the eye and the inner eyelids. It can be caused by allergies, irritating substances, or infection from a virus or bacteria. Pinkeye that is caused by an infection can spread easily from person to person. Children may rub their eyes and transmit the infection to other children at preschool, day care, or the playground.Symptoms :
- Redness in one or both eyes.
- Itchiness in one or both eyes.
- A gritty feeling in one or both eyes.
- A discharge in one or both eyes that forms a crust during the night that may prevent your eye or eyes from opening in the morning.
- Sensitivity to light, called photophobia.
Consult an ophthalmologist, especially if the child is a newborn. Bacterial conjunctivitis usually lasts about 5–10 days to heal and Viral conjunctivitis can last as long as 14 days. Topical antibiotics, a combination of such drugs is the generally prescribed medication which helps the disease clear up faster. Proper hygiene is also advised for faster resolution. Allergic conjunctivitis on the other hand may take months to resolve with a waxing and waning course. Each bout of allergic pink eye needs an ophthalmologist consultation before starting any medication.
However, simple preventive strategies can reduce the spread of the infection and lower the risk of recurrent conjunctivitis:
- Encourage toddlers to avoid touching or rubbing their eyes.
- Avoid school for children with fever or thick eye discharge till they recover.
- Do not share eye care products.
- Encourage and practice frequent washing of hands.
- Restrict children from touching their friends’ faces.
5. Blocked Tear Ducts :
Tear ducts are small openings at the inner corner of the eyelids. Tears drain through this tear ducts and wash over the eyes to keep them moist and clean. They then drain into a larger passage from the eye to the inside of the nose. This is called the tear duct (nasolacrimal duct). When a tear duct is blocked, the tears cannot drain.
A child with a blocked tear duct may experience:
- more tearing than usual (even when the child isn’t crying)
- dried crusting on the eyelashes
- mild redness or irritation of the eyes or eyelids (from the child rubbing them)
Congenital nasolacrimal duct obstruction is a condition where the child is born with tear gland obstruction. However, they may also acquire it later in life. In case a child has a blocked tear duct, ophthalmologists generally suggest massaging the eye several times a day at home for a few months. Massaging can help open the blockage. However, in case the blockage persists, or there are any infections, ophthalmologists decide on the treatment methods based on eye examinations, symptoms, severity of the condition, child’s age and general health.
To open a tear gland block, an ophthalmologist can undertake different types of surgery such as:
- probing the blocked duct using a thin metal instrument
- placing special tiny tubes to stretch the tear duct.
- using a catheter that expands like a balloon to open the tear duct.
After surgery, the doctor will prescribe an antibiotic ointment or drops to use while the tear duct heals.