Like adults, children suffer from blurred vision caused by refractive error:
Myopia or nearsightedness is the inability to see clearly at a distance while near vision remains unaffected. Children with myopia may struggle seeing distance objects like the board at school.
Hyperopia or farsightedness is the inability to see close-up objects clearly while distance vision is less affected. A small amount of farsightedness is normal in children and is easily overcome by their tenacious eye focusing muscles. Children who are abnormally farsighted may struggle with vision at distance and near and can sometimes have eye crossing.
Astigmatism is a condition where the eye is slightly misshapen. An eye without astigmatism is perfectly spherical, or shaped like a baseball, and focuses light in only one plane. An eye with astigmatism is more oblong, or shaped like a football, and focuses light in two planes. Astigmatism is a normal occurrence and simply requires a different lens to correct than eyes without astigmatism.
Strabismus is a term that refers to any eye misalignment when one eye turns in (esotropia), out (exotropia), up or down (hyper/hypotropia.) Although it is normal for a child’s eyes to deviate in the first few months of life, an ophthalmologist should address any eye misalignment even intermittently noticed after 3 months old.
Amblyopia, often referred to as lazy eye, is the brain’s inability to properly connect to or use one or both eyes. Amblyopia occurs when the image from the eye is not properly transmitted to the brain leading to poor development of visual receptors within the brain. A child’s visual system develops from birth to around age 8 and it is only within this window that amblyopia is treatable.
Deprivation Amblyopia is caused by structural anomalies within the eye like cataracts or corneal scars causing habitual blurred vision.
Strabismic Amblyopia is caused by chronic eye misalignment resulting in double vision. Frequently, the child’s brain will actively ignore one eye to alleviate the double vision halting visual development in the suppressed eye.
Refractive Amblyopia is caused when the two eyes are not focused together. One eye may be normal and the other very farsighted or have a high amount of astigmatism causing constant blurred vision to one eye.
Conjunctivitis or pink eye is swelling of the conjunctiva, the thin clear membrane covering the white part of the eye and the inside of the lids.
Allergic Conjunctivitis is caused when allergens come into contact with the ocular surface. Allergic conjunctivitis often flares up seasonally with increased environmental allergens but can be caused by animals and other substances within homes. Allergic conjunctivitis is often associated with red, itchy and puffy eyes with mild amounts of watering and mucous discharge. Allergic conjunctivitis is not contagious and is often treated with over the counter drops.
Bacterial Conjunctivitis is caused by a bacterial infection of the conjunctiva. Along with redness and swelling, thick mucus discharge is typically present. Bacterial conjunctivitis is commonly treated with antibiotic eye drops and can be spread from person to person, so careful hand washing and limited contact with affected individuals should be observed.
Viral Conjunctivitis is caused by viral infection of the conjunctiva similar to infections that cause cough, runny nose and sore throat. In addition to redness and swelling, viral conjunctivitis is usually accompanied by pain, watering, and ropey strands of discharge. As antibiotic drops are not helpful with viral infections, most infections are left to run their course. In severe cases anti-viral medications can be prescribed. Viral conjunctivitis can be extremely contagious, so limited contact with affected individuals and proper hand hygiene is recommended.
The vast majority of headaches in children can be attributed to non-ocular causes. Migraines, stress-tensions headaches, sinus and teeth problems are the most common. Children with chronic headaches should be evaluated by their pediatrician to look for systemic causes.
Children who are excessively farsighted may suffer from chronic headaches due to the need to constantly focus the eyes to see clearly. Undiagnosed eye misalignment also can cause headaches. Increased pressure or inflation within the eye itself can cause eye pain and headaches and is usually accompanied by redness, tearing or light sensitivity.
A thorough dilated eye exam with an ophthalmologist is the best way to rule ocular causes for headaches in children.
Blocked Tear Ducts
Blockage of the tear drainage system is common in infants and newborns and is caused by malformations in the nasolacrimal (tear drainage) system. Blockage of the tear drainage system causes tears to pool up on the surface of the eye and eventually spill over and run down the face. Children with blocked tear ducts often have red, irritated skin around the eye due to chronic tearing. Secondary eye infections are common due to buildup of stagnant tears on the surface of the eye, often leading to goopy mucus discharge.
Luckily, around 90 percent of cases will spontaneously resolve within the first year of life, so delaying treatment until one year of age is common. Topical antibiotics can be used to treat secondary bacterial infections as needed and tear duct massage can help open or express foreign matter through the system if possible.
Tear duct probing where a smooth probe is passed through the nasolacrimal system is performed if tearing persists past one year of age. The success rate of tear duct probing is very high, but in severe cases a secondary stent or tube may be placed.
Convergence insufficiency (CI) is the inability to turn the eyes together for prolonged use when looking up close. The eyes naturally converge together when reading or performing near tasks. In patients with CI, it takes increased effort to hold/bring the eyes together when focusing on a near object.
Patients with symptomatic CI typically complain of the following symptoms when reading or performing near tasks: headache, double vision, blurred vision, having to close one eye to see clearly, words that seem to move on the page, getting tired of reading after a short period of time, a pulling sensation in the eyes, eye pain or discomfort with reading.
A thorough dilated eye exam with assessment of eye movement, alignment, vergence and focus is needed to diagnose CI. Not all children with convergence insufficiency are symptomatic; therefore, not all require treatment. For those who have clinical findings and are symptomatic, simple at-home eye exercises or at-home computer based training is recommended. In the most severe cases, in-office exercises are accompanied by at-home training.