The American Academy of Ophthalmology (AAO) and the American Academy of Pediatrics (AAP) recommend that children be screened in 4 stages.

1. In the newborn nursery:
   pediatricians or family physicians should examine all infants; ophthalmologists should examine all high-risk infants.
   
2. By age 6 months:
   pediatricians or family physicians should screen all infants.
   
3. At age 3 1/2 years:
   pediatricians, family physicians or ophthalmologists should examine all children.
   
4. At age 5 years and older:
   pediatricians or family physicians should screen children annually if this is not provided by school personnel or volunteer organizations.

Examination of Newborn Infants
In the newborn nursery, there are two categories of examination:

1. Routine screening for low-risk infants
   All infants not at high risk should have an eye examination by a pediatrician or a family physician. Examination procedures in the newborn nursery should include examination of the eye with a penlight, the corneal light reflex test, and simultaneous examination of the retinal red reflexes with an ophthalmoscope.
2. Ophthalmologic consultation for high-risk infants
   Because of the urgency and high yield of examination, ophthalmologists should evaluate those at risk to develop retinopathy of prematurity (ROP), and those with a family history of retinoblastoma, cataracts, or metabolic disease.

Retinopathy of prematurity (ROP) occurs particularly in infants with prematurity, low birth weight less than 1,700 grams), or oxygen administration but may occur in the absence of all of these condi- tions. Each year ROP causes some degree of visual loss in approximately 1,300 infants and severe impairment in 400 to 800 infants in the U.S. In the majority of infants, ROP is a transient disease with spontaneous regression. However, there are patients with progressive ROP.

A recent multi-center trial has disclosed that cryotherapy (retinal freezing) reduces by 50% the number of unfavorable outcomes (such as retinal detachments) in the short term. Long-term outcomes are not yet known. The present recommendation is that premature babies be examined between 6 and 9 weeks of age to rule out the development of ROP.

Retinoblastoma is a life-threatening condition that may be detected within the first few months of life. It is the most common intraocular malignancy in children and occurs once in every 20,000 live births, resulting in 200-300 new cases annually in the U.S. Twenty-five percent of patients have a family history of retinoblastoma. Sixty percent of retinoblastoma patients will present with a fundus white reflex and an additional 20% with strabismus (a deviated eye). The prognosis for vision and life is directly related to the size and extension of the tumor.

Cataracts are the most common cause of a white pupil (leukokoria) at birth. The incidence may be as high as 1 in every 1,000 live births in the U.S. Because they interfere with the normal development of the visual system, cataracts in infants may require surgery within the first few weeks of life, followed by contact lens fitting or aphakic glasses and amblyopia treatment.

Examination by 6 Months of Age
Examination at this time should include the determination of the infant's ability to fix on a penlight or toys, aversion to occlusion of one eye, and exclusion of such external abnormalities as proptosis and lid tumors. To screen for ocular alignment, the examiner should use the corneal light reflex test and the cover/uncover test.

Simultaneous examination of both retinal red reflexes is useful, both as a test of ocular alignment and to rule out abnormalities of the ocular media.

Indications for referral include the inability to fix on a penlight, aversion to occlusion of one eye, lid or corneal abnormalities, strabismus (ocular misalignment), nystagmus, or abnormal red reflexes.

Examination at 3 1/2Years of Age
Examination at this time should include visual acuity, ocular alignment, and the fundus. Visual acuity testing can be performed with Allen picture cards, Snellen Es, or ABCs. Testing should be completed with the corneal light reflex test, the cover/ uncover test, and the fundus exam. Children with a visual acuity of 20/50 or worse or a two-line difference between the two eyes, strabismus or any ocular abnormality should be referred for ophthalmologic examination.

Examination at Age 5 Years and Older
Vision screening at this time should include visual acuity (Snellen ABCs) and the corneal light reflex test. Children with a visual acuity of 20/40 or worse or a two-line difference between the two eyes (i.e., 20/30 OD and 20/20 OS), strabismus, or any ocular abnormality should be referred for ophthalmologic evaluation.

Vision Screening by Primary Care Physicians

References: American Academy of Ophthalmology