A subcommittee for the American Academy of Pediatrics (AAP) has released a policy statement on eye examinations in infants, children, and young adults. The report focuses on the importance of early detection and prompt treatment of ocular disorders in children to avoid permanent visual impairment. The original report was published in the April 2003 issue of Pediatrics.
Eye examinations and vision assessment are essential for detecting conditions that could lead to blindness, signify systemic disease, lead to learning problems, or be life threatening. Children should have eye examinations as neonates and at all subsequent well-child visits.
Assessments should be age-appropriate, and the most sophisticated test the child is capable of performing should be used (see accompanying table). Children do not complain of vision problems, so screening should be started as soon as possible, usually by three years of age. If a child is unable to be tested after two attempts and an abnormality is suspected, referral may be necessary. Premature infants; those with family histories of congenital cataracts, retinoblastoma, and metabolic or genetic disease; children with significant developmental delay or neurologic disorders; and those with a systemic disease also may need to be referred to a subspecialist.
|Function||Recommended tests||Referral criteria||Comments|
|Distance visual acuity||Snellen letters, Snellen numbers, tumbling E, HOTV, picture tests (Allen figures, LEA symbols)||Fewer than four of six correct on 20-foot line (15-foot line for children six years and older) with either eye tested at 10 feet monocularly (i.e., less than 10/20 or 20/40; 10/15 or 20/30 for children six years and older) or two-line difference between eyes, even within the passing range (i.e.,10/12.5 and 10/20 or 20/25 and 20/40; 10/10 and 10/15 or 20/20 and 20/30 for children six years and older)||Tests are listed in decreasing order of cognitive difficulty; the highest test that the child is capable of performing should be used; in general, the tumbling E or the HOTV test should be used for children three to five years of age and Snellen letters or numbers for children six years and older.|
|Testing distance of 10 feet is recommended for all visual acuity tests.|
|A line of figures is preferred over single figures.|
|The nontested eye should be covered by an occluder held by the examiner or by an adhesive occluder patch applied to the eye; the examiner must ensure that it is not possible to peek with the nontested eye.|
|Ocular alignment||Cross cover test at 10 feet (three meters)||Any eye movement||Child must be fixing on a target while cross cover test is performed.|
|Random dot E stereo test at 40 cm||Fewer than four of six correct||Direct ophthalmoscope used to view both red reflexes simultaneously in a darkened room from two to three feet away; detects asymmetric refractive errors as well.|
|Simultaneous red reflex test (Bruckner test)||Any asymmetry of pupil color, size, brightness|
|Ocular media clarity (e.g., cataracts, tumors)||Red reflex||White pupil, dark spots, absent reflex||Direct ophthalmoscope, darkened room. View eyes separately at 12 to 18 inches; white reflex indicates possible retinoblastoma.|
From newborn to three years of age, the eye evaluation should include vision assessment, ocular history, external inspection of the eyes and lids, ocular motility assessment, pupil examination, and red reflex examination. For children older than three years, the evaluation also should include an age-appropriate visual acuity measurement and an attempt at ophthalmoscopy. All children should have regular eye examinations, and newborns should be evaluated for structural abnormalities such as cataracts, corneal opacities, and ptosis. Parents should be notified of all test results and given clear instructions for any follow-up care.
The standard assessment strategy for children younger than three years is to determine whether each eye can fixate on an object, maintain fixation, and then follow the object into various gaze positions. The test should be performed binocularly and then monocularly. If the child is unable to follow these maneuvers, it is an indication of significant visual impairment. The child must be awake and alert because disinterest or poor cooperation can mimic a poor vision response. For children older than three years, physicians can use picture cards, wall charts, or vision testing machines.
The ocular history should include observations from the parents and any relevant family history involving eye disorders or early childhood use of glasses in parents or siblings. External examination includes a penlight evaluation of the lids, conjunctiva, sclera, cornea, and iris. Ocular alignment is important because strabismus can develop at any age and can represent serious orbital, intraocular, or intracranial disease. The corneal reflex test, cross cover test, and random dot E stereo test are useful in determining true strabismus.
The pupils should be equal, round, and reactive to light in both eyes. Slow or poorly reactive pupils may indicate significant retinal or optic nerve dysfunction. Sympathetic or parasympathetic abnormalities are usually indicated if one pupil is larger than the other. Larger asymmetries (greater than 1 mm) can be caused by neurologic disorders. The red reflex test is used to detect opacities in the visual axis, abnormalities of the back of the eye, and amblyogenic conditions. The red reflex seen in each eye should be bright reddish-yellow (light gray in darkly pigmented, brown eyes) and identical in both eyes. Any asymmetry in color, brightness, or size is indicative of a problem.
Visual acuity testing is recommended for all children beginning at three years of age. If the child does not cooperate, another attempt should be made in four to six months. If the child is four years or older, the second attempt should be made in one month.