Pediatric Ophthalmology and Strabismus

Strabismus: Strabismus is a visual problem in which the eyes are not aligned properly and point in different directions. One eye may look straight ahead, while the other eye turns inward, outward, upward, or downward. ¹ The eye turn may be consistent (constant), or it may come and go (intermittent). Which eye is straight (and which is misaligned) may switch or alternate in order to avoid diplopia or double vision.

Strabismus is a common condition among children. It can also occur later in life. It may run in families; however, many people with strabismus have no relatives with the problem. Condition can be corrected by use of glasses and surgery if not improved by glasses.

Error of Refraction: The cornea and lens of the eye helps focus. Refractive errors are vision problems that happen when the shape of the eye keeps one from focusing well. The cause could be the length of the eyeball (longer or shorter), changes in the shape of the cornea, or aging of the lens.
Four common refractive errors are
•   Myopia, or nearsightedness - clear vision at near but blurry in the distance
•   Hyperopia, or farsightedness - clear vision in the distance but blurry at near
•   Presbyopia - inability to focus close up as a result of aging
•   Astigmatism - focus problems caused by an irregularity in the shape of the cornea

The most common symptom is blurred vision. Other symptoms may include double vision, haziness, glare or halos around bright lights, squinting, headache, or eye strain.
Glasses or contact lenses can usually correct refractive errors. Laser eye surgery may also be a possibility. ²

Amblyopia or “Lazy Eye” : Amblyopia is a type of poor vision that happens in just 1 eye. It develops when there is a significant difference in the vision between both eyes. In order to avoid double vision, the brain does not process the image of the poorer eye and only processes that of the better eye. Over time, the brain relies more and more on the stronger eye while vision in the weaker eye gets worse and becomes the “lazy eye”. ³
Refractive errors, strabismus and unilateral cataracts are some eye conditions that can lead to amblyopia.
Treatment include addressing the cause such as use of eyeglasses, surgical correction of strabismus, removal of cataracts and scheduled patching of the better eye.

Retinopathy of Prematurity (ROP)
Retinopathy of prematurity (ROP) is a potentially blinding disease caused by abnormal development of retinal blood vessels in premature infants. When a baby is born prematurely, the retinal blood vessels can grow abnormally. Most ROP resolves without causing damage to the retina. When ROP is severe, it can cause the retina to pull away or detach from the wall of the eye and possibly cause blindness. Babies 1250 grams or less and are born before 31 weeks gestation are at highest risk.
ROP can be prevented by early screening and treatment. A dilated retinal exam is usually done at 30 days of life or prior to discharge whichever comes first.
Treatment include laser ablation of the premature retina or intravitreal injection of medications.

Retinoblastoma (Rb) is a rare form of cancer that rapidly develops from the immature cells of a retina. It is the most common primary malignant intraocular cancer in children, and is commonly found in young children up to 3 years old.

Most common presentation is leukocoria or cat’s eye reflex, deteriorating vision, red and irritated eye, squinting or enlargement of the eye in advanced cases.

Almost half of children with retinoblastoma have a hereditary genetic defect associated with retinoblastoma. In other cases, it is caused by a congenital mutation in the chromosome 13 gene 13q14 (retinoblastoma protein)

Though most children survive this cancer, they may lose their vision in the affected eye(s) or need to have the eye removed.

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