93: Eye Disorders of the Newborn

The infant's first eye examination is performed sometime after birth and prior to discharge home. The extent of the examination should be appropriate to the infant's condition. This initial selective screening examination assesses structural development of the eyes and the relationship of the eyes to the overall facies. In addition, reactivity of the pupils and the red reflex are assessed. The eye examination also provides a good opportunity to observe an infant's resting state and his or her ability to transition from one state to another. Observations that give information about the infant's general well-being and maturity include apparent awareness and visual interest in the surroundings as opposed to abnormal staring or absent visual fixation. In otherwise healthy infants, assessment of visual acuity is delayed until early childhood when cooperation with the eye examination can be expected. Normal findings that resolve include edema, eversion, bruising, hemorrhage, and nevus simplex. (See also Chapter 6.)

The American Academy of Pediatrics (AAP) recommends an age-appropriate assessment in the newborn period: ocular history, vision assessment (ability to fix and follow objects after 3 months of age), external inspection of the eyes and lids (conjunctiva, sclera, cornea, iris, and lids), ocular motility assessment, pupil examination (equal, round, and reactive to light), red reflex examination (should be bright reddish-yellow, or light gray in brown-eyed infants, and identical in both eyes). Newborns should be evaluated for cataracts, ptosis, and corneal opacities. Any abnormalities on examination should be referred to a pediatric ophthalmologist. Infants at high risk of eye problems (premature, significant neurological or developmental difficulties, metabolic or genetic diseases, positive family history of congenital cataracts, retinoblastoma, any systemic diseases associated with eye abnormalities) should be referred for a specialized eye examination by a pediatric ophthalmologist.

Structure and function of the eye are dynamic processes that begin early in pregnancy and continue throughout childhood. In term infants, the eye and visual pathway system are immature with most neonates being farsighted. During early school age, they become more nearsighted. Binocularity is established by 3–4 months of age. By 4–5 months, infants can fixate on an image with both eyes simultaneously with a steady gaze; the ability to distinguish color begins at ∼5 months. Visual acuity in infants ranges from 20/400 to 20/50. The optic nerve is completely myelinated by 2 years of age and visual acuity reaches 20/40 by that time.

The pupils are small with undeveloped reflexes until about 5 months of age. Transient nystagmus is common in infants <6 months. Extraocular muscle function is poorly coordinated for the first 6 months of life, resulting in intermittent convergent strabismus. Accommodation and convergence should be established by 24 months. There is little pigment in the iris at birth; pigmentation of the eye is complete by 6–12 months of age. The lacrimal apparatus is not fully developed at birth. Neonates don't produce tears until ∼4–6 weeks of age. Both corneal and blink reflexes are present at birth. The eye size reaches adult proportion by about 8 years of age.

1. Definition. Amblyopia is a reduction in corrected visual acuity in the absence of organic eye disease. It results from unequal visual stimulation during the sensitive period of visual development and is the most common cause of monocular vision loss in children.

2. Incidence. Estimated prevalence is 2–5% in the United States. This condition affects 2–3 out of every 100 children.

3. Pathophysiology. Amblyopia may be caused by any condition that affects normal visual development or use of the eyes. There are 3 major etiologies for amblyopia in the neonate.

   1. Strabismus. This is the preference of one eye when the visual axes are misaligned and is the most common contributing factor. It develops whether it is from esotropia, exotropia, or hypertropia.

   2. Refractive errors. Amblyopia resulting from refractive errors can be divided into 2 types: anisometropic and isometropic. Anisometropic amblyopia results from significant inequality of the refractive errors in each eye, blunting the development of the visual pathway in the affected eye. Isometropic amblyopia occurs when the refractive errors in the 2 eyes are equal.

   3. Deprivation. The least common condition, congenital or early-acquired opacity, causes deprivation amblyopia. This can be the most severe and damaging type. Cataracts, corneal lesions, or ptosis blocks or distorts the retinal image formation. This can affect one or both eyes and may develop as early as 2–4 months.

4. Risk factors. Low birthweight, prematurity, familial factors, and certain congenital anterior lens opacities with significant anisometropia.

5. Clinical presentation. Strabismus is recognized as a consistently deviating eye in the first few months after the newborn period. Diagnosis is made during the newborn or early infant eye examination or when there is evidence of reduced visual acuity that cannot be explained by physical abnormalities.

6. Management. Treatment is individualized depending on the cause. The treatment for strabismus is patching of the preferred eye or surgical correction. Refractive amblyopia is treated with patching or glasses. Surgical interventions are needed for deprivation amblyopia.

7. Prognosis. It is critical that these be diagnosed and treated as early as possible. Most vision loss is preventable or reversible with the right intervention for the individual etiology. The recovery depends on the maturity of the visual connections, the length of deprivation, and the age at which therapy is begun.

1. Definition. Anophthalmos is absence of ocular tissue in the orbit. Microphthalmos describes an eye that measures <15 mm in diameter after birth.

2. Incidence. The prevalence of anophthalmos and microphthalmos are generally estimated to be 3 and 14 per 100,000 births, respectively. The combined prevalence may be up to 30 per 100,000 births.

3. Pathophysiology. Anophthalmos is caused by failure of development of either optic vesicle or regression after initiation of vesicle development. May occur in isolation or as part of a syndrome.

4. Risk factors. Advanced maternal age, multiple births, prematurity, and low birthweight.

5. Clinical presentation. Either the presence of no eye tissue or a small orbit. Diagnosis is made by inspection, palpation, and imaging. Ultrasound is commonly used to determine length of the globe in microphthalmia. Computed tomography (CT) and magnetic resonance imaging (MRI) can facilitate diagnosis of anophthalmia. Detectable function may be present in microphthalmic cases.

6. Management. Conservative approaches include refracting the eyes and treating any underlying amblyopia. In unilateral cases, the “good” eye must be protected and any visual deficit managed appropriately. Reconstructive surgical interventions allow for growth of the orbit and prevention of soft tissues and orbit hypoplasia.

7. Prognosis. Visual development depends on the degree of retinal development and other ocular characteristics in microphthalmic patients. Therapy is aimed at maximizing existing vision and enhancing cosmetic appearance rather than improving sight.

1. Definition. Colobomas are cleft-shaped fissures in the eyelid, iris, ciliary body, retina, choroid, or optic nerve. They are usually restricted to the iris.

2. Incidence. Ocular colobomas occur in 1 per 2077 live births.

3. Pathophysiology. Incomplete embryologic closure of fetal fissures that may be associated with persistence of hyaloid vessels and papillary membrane.

4. Risk factors. The majority are sporadic, but there is an increased incidence in infants with trisomy 13 and infants with CHARGE syndrome (coloboma, heart defects, choanal atresia, retarded growth and development, genital abnormalities, and ear anomalies), or as a result of maternal ingestion of LSD or thalidomide. Familial colobomas are autosomal dominant.

5. Clinical presentation. A keyhole-shaped defect that may be seen in a variety of optic structures.

6. Management. Indicated in a severe defect or when an eyelid coloboma prevents adequate lid closure.

7. Prognosis. Dependent on the location of the coloboma. A coloboma in the iris would not affect vision. A coloboma that includes the optic nerve, the macula, and other parts of the retina can cause legal blindness.

1. Definition. A nonspecific reaction to a change in the lens metabolism leading to lens opacification.

2. Incidence. Estimates are 1.2–6.0 cases per 10,000 in the United States.

3. Pathophysiology. Any process that alters the glycolytic pathway or epithelial cell mitosis of the avascular lens causes cataracts.

4. Risk factors. About 25% of the cases are hereditary; the most frequent mode of transmission is autosomal dominant; about one-third of cases occur sporadically.

   1. Metabolic causes. Hypoglycemia, hypoparathyroidism, mannosidosis, maternal diabetes, galactosemia, hypocalcemia, and vitamin A or D deficiency.

   2. Congenital infections. Infants with rubella, herpes simplex, and varicella can have congenital cataracts.

   3. Other causes. In utero radiation exposure and associations with specific genetic syndromes (trisomy 21, Stickler, Smith-Lemli-Opitz).

5. Clinical presentation. The newborn presents with a white papillary reflex or leukocoria. Cataracts in infants may be transient and disappear spontaneously within a few weeks. Lens opacities may be isolated or associated with other eye anomalies or systemic conditions. Cataracts seen with congenital rubella are characteristically total or near-total opacities in a smaller than normal lens. Abnormalities of the retinal pigment, “salt and pepper” changes, are typically seen.

6. Management. The initial workup includes the many causes and associations. Maternal and infant history direct laboratory evaluation. An ophthalmologic slit lamp confirms the presence of a cataract. If the cataract directly threatens vision, then prompt surgical removal is indicated to avoid legal blindness from deprivation amblyopia. Infants will require significant visual rehabilitation.

   1. Optical devices are used to provide focus after the lost lens. Contact lenses are used early.

   2. Occlusion therapy of the better eye to reverse amblyopia may be necessary. Length of treatment ranges from 1 to 8 weeks in infants <1 year of age.

7. Prognosis. Cataracts lead to varying degrees of visual impairment from blurred vision to blindness, depending on the extent and location of the opacity.

1. Definition. Increased ocular pressure in the aqueous humor that eventually causes damage to the optic nerve.

2. Incidence. It is estimated to affect <1% of all children.

3. Pathophysiology. Primary congenital glaucoma is caused by structural abnormalities of the eye drainage channels. Secondary causes include retinopathy of prematurity, persistent fetal vasculature, congenital rubella, and homocystinuria.

4. Risk factors. Males are found to have a higher incidence of the disease, comprising ∼65% of cases. The disease is typically autosomal recessive. Infants with galactosemia, lysosomal storage disorders, and peroxisomal disorders can all present with glaucoma.

5. Clinical presentation. Corneal cloudiness, photophobia, lacrimation, buphthalmos, and eye rubbing.

6. Management. Diagnosis is made by measuring ocular pressure. Periodic monitoring of ocular pressure and vision is necessary. Infants usually require surgery to increase drainage.

7. Prognosis. Early intervention is preferred as there is increased risk for blindness if left untreated.

See Chapter 53.

See also Chapter 53.

1. Definition. Congenital obstruction of the nasolacrimal duct.

2. Incidence. This common abnormality is found in 2–6% of all newborns.

3. Pathophysiology. The obstruction is caused by an imperforate membrane at the end of the nasolacrimal duct.

4. Risk factors. Children with Down syndrome, craniosynostosis, Goldenhar sequence, clefting syndromes, hemifacial microsomia, or any midline facial anomaly are at an increased risk for congenital nasolacrimal duct obstruction.

5. Clinical presentation. The signs of obstruction are an increase of mucus or mucopurulent discharge and epiphora. The periocular skin is sometimes chapped. The globe is usually white. Pressure over the lacrimal sac produces a reflux of mucoid or mucopurulent material from the punctum.

6. Management. Treatment consists of initial observation for resolution followed by probing of children with persistent duct obstruction. Medical management includes observation, lacrimal massage, and treatment with topical antibiotics.

7. Prognosis for resolution is good.

1. Definition. A unilateral or bilateral decrease in the vertical distance between the upper and lower eyelids.

2. Incidence. The frequency of congenital ptosis in the United States has not been reported. However, in 70% of known cases, only one eye is affected.

3. Pathophysiology. Due to dysfunction of the levator palpebrae muscle.

4. Risk factors. It may be transmitted as an autosomal dominant condition or caused by third-nerve palsy.

5. Clinical presentation. Ptosis can affect one or both eyes. With partial dysfunction the eyelid droops; with complete dysfunction of the muscle, there is no elevation of the eyelid during an upward gaze. Infants with mild unilateral ptosis should be evaluated for Horner syndrome.

6. Management. Infants should be monitored every 3–12 months for signs of amblyopia. Surgical correction of congenital ptosis can be undertaken at any age depending on the severity of the disease. Earlier intervention may be required if significant amblyopia or ocular torticollis are present.

7. Prognosis. Repair of congenital ptosis can produce excellent functional and cosmetic results. Of patients who require surgical intervention, 50% or more may require repeat surgery in 8–10 years following the initial surgery. With careful observation and treatment, amblyopia can be treated successfully.

1. Definition. Chronic granulomatous inflammation of the meibomian glands developing away from the lid margins.

2. Incidence. Unknown.

3. Pathophysiology. This is caused by a blockage in one of the ducts that drains the glands.

4. Risk factors. Males and females are equally affected.

5. Clinical presentation. A nontender, firm nodule is seen deep within the eyelid; usually centered on an eyelash; usually not seen in neonates.

6. Management. Small, asymptomatic chalazia can be ignored. Treatment includes massage, moist heat, and topical mild steroid drops. Management of infected chalazia includes antibiotics, heat, and possible incision and drainage.

7. Prognosis for resolution is good.

1. Definition. A cancerous tumor of the retina.

2. Incidence. Retinoblastoma affects 1 in every 15,000–30,000 live babies that are born in the United States. It is the most frequent tumor of the eye.

3. Pathophysiology. In all cases, it is caused by an abnormality in chromosome 13, which is responsible for controlling retinal cell division.

4. Risk factors. The majority of families have no family history, though there is an increased risk of transmission once in the family. It affects children of all races and both boys and girls.

5. Clinical presentation. The majority of infants present with a white papillary reflex (leukocoria). Other signs are strabismus, poor vision, enlarged pupils, or inflammation of tissue around the eye. Most cases (75%) involve only one eye.

6. Management. Diagnosis is made during an ophthalmologic examination under general anesthesia. Treatment is customized for each patient. Enucleation of the affected eye has been standard treatment of this tumor, though intraoptical chemotherapy is currently being used in some institutions. Radiation, laser therapy, cryotherapy, laser reduction, and chemoreduction are also used.

7. Prognosis. Long-term prognosis is good. Most children with retinoblastoma survive. In the United States, nearly 98% of children survive, but not so in less advanced countries where about 50% of children die from tumor spread. Long-term ocular and pediatric examinations are advised for the child.