Commonly Missed Diagnoses in the Childhood Eye Examination JOHN W. SIMON, M.D., and PAMELA KAW, M.D., Albany Medical College, Albany, New York

Early and accurate detection of eye disorders in children can present a challenge for family physicians. Visual acuity screening, preferably performed before four years of age, is essential for diagnosing . Cover testing may disclose small- angle or intermittent . Leukocoria, which is detected with an ophthal- moscope, may indicate or . Children with may have light sensitivity and enlargement of the , and that does not respond quickly to treatment may reflect more serious ocular inflammation. Children with serious eye injuries often present to the primary care physician. Nys- tagmus and many systemic conditions are associated with specific eye findings. (Am Fam Physician 2001;64:623-8.)

ome eye disorders in children The purpose of this article is to facilitate must be diagnosed at an early age recognition and referral of children with sig- to prevent loss of vision and to nificant eye disorders, emphasizing eight con- optimize treatment outcomes.1-4 ditions that are easily missed during visits to Unfortunately, effective screening the primary care office. These conditions are Sfor eye disorders and visual function can be amblyopia, small-angle strabismus, leukoco- difficult for primary care physicians. Young ria, glaucoma, ocular inflammation, eye children may not be willing participants in trauma, and systemic disorders the screening process, and interesting fixa- that affect the eye. tion devices are often not available in the office. In addition, some of the diagnoses are Amblyopia complex. The involvement of pediatric oph- Amblyopia (lazy eye) is defined as a thalmologists with specialized training, reduction in best-corrected visual acuity expertise and examination equipment is that is not directly attributable to any struc- often required. tural abnormality of the eye or visual path- Despite these difficulties, most significant way. With a prevalence of 2 percent,6 it is the eye problems in children can be identified most common cause of uncorrectable loss of with effective screening techniques. The vision in children. The visual outcome can American Academy of Family Physicians, range from 20/25, or nearly normal, to worse the American Academy of Pediatrics and the than 20/200, or legally blind. With effective American Association for Pediatric Oph- detection and early treatment, most vision thalmology and Strabismus have endorsed loss associated with this condition can be the role of the primary care physician in avoided. screening children for eye disorders.5 If pos- Most cases of amblyopia affect only one sible, all children should have their monoc- eye, but some cases are bilateral. Ophthalmol- ular visual acuity tested before four years ogists refer to anisometropic amblyopia when of age. one eye is involved and isometropic ambly- opia when the condition is bilateral. Although the first few years are the most crucial, ambly- opia may occur in children as old as four to All children, if possible, should have their monocular visual six years. There are three major categories of acuity tested before four years of age. amblyopia, each with special problems for diagnosis and treatment.7

AUGUST 15, 2001 / VOLUME 64, NUMBER 4 www.aafp.org/afp AMERICAN FAMILY PHYSICIAN 623 strabismus, this passive treatment may be The most common cause of uncorrectable loss of vision in effective after several months. The classic children is amblyopia. therapy is occlusion or patching of the nor- mal eye. Nearly full-time occlusion is often prescribed initially. Follow-up evaluations are recommended at intervals that vary depend- STRABISMIC AMBLYOPIA ing on the age of the child, and are more fre- Strabismic amblyopia is the most common quent for younger children. Recently, “penal- type of amblyopia. The deviating eye which ization” with atropine to blur the dominant may turn in (), out (), up eye has been increasingly used as an alterna- () or down (hypotropia), is sup- tive to patching. pressed in order to prevent double vision. Treatment is always most effective if started This suppression can become so effective that early. Children with suspected strabismus, the affected eye loses its visual potential. The even if mild or intermittent, should be diagnosis becomes difficult when the devia- referred for evaluation beginning around tion is small and thus is not obvious. four to six months of age. An infant with a constant large-angle esotropia can be referred REFRACTIVE AMBLYOPIA even earlier. hemangiomas or other Refractive amblyopia is the most difficult masses, even if subtle, can cause changes in type of amblyopia to detect. If the two eyes refraction and may result in refractive ambly- have significantly different refractive states, opia; children with these problems should be the young child may rely on the sight of the referred as early as possible. The ophthalmo- more focused eye, causing the other eye to scope should be used to examine the red lose its visual potential. The child will appear reflex beginning in the neonatal period, and to see normally at home and in the primary children with suspected media opacities care office because the normal eye is being should be referred urgently. Children with a used for visual tasks. If both eyes are out of family history of amblyopia are at increased focus, both may become amblyopic. risk, and the importance of early vision screening cannot be overemphasized. DEPRIVATION AMBLYOPIA Deprivation amblyopia is the most severe Small-Angle Strabismus type in terms of loss of vision. It typically Although many cases of strabismus are affects children with unilateral or bilateral obvious, others may be difficult to detect congenital but also may occur in because the deviations are small or intermit- those with corneal or vitreous opacity, severe tent. Accommodative esotropia, which usu- (droopy eyelid) or excessive patching. ally begins in toddlers who are farsighted, is Deprivation amblyopia develops because the an example. Because of their eyes’ refractive does not receive a clear image. In some state, these children are forced to accommo- cases, the cataract may not be apparent on date excessively and induce accommodative casual penlight inspection but is detected by convergence, normally part of the near reflex, the absence or distortion of on oph- even when looking at distant objects. Treat- thalmoscopic examination. ment with eyeglasses, including bifocals in some cases, may help to align the eyes. Unfor- TREATMENT tunately, small-angle esotropia is at least as Treatment of amblyopia begins with likely as more significant deviations to be appropriate optical correction using eye- associated with amblyopia.8 Cover testing glasses or contact lenses. In the absence of (Figure 1), with the examiner briefly covering

624 AMERICAN FAMILY PHYSICIAN www.aafp.org/afp VOLUME 64, NUMBER 4 / AUGUST 15, 2001 Pediatric Eye Exam

closes an eye on a bright day may be describ- ing intermittent exotropia. Hypertropia and hypotropia, or upward and downward deviations, may be caused by a fourth cranial nerve/superior oblique palsy. Although the deviation may not be apparent on casual inspection, tilting the head to the side of the palsy may cause the affected eye to rise. It is unusual for children to develop stra- bismus as the only manifestation of underly- ing neurologic disorders, but acquired devia- tions related to specific cranial nerve palsies should raise suspicion.

Leukocoria Alteration in the pupillary light reflexes (called leukocoria if the appears white) may indicate a disorder anywhere within the eye.10 Disorders include , blood ILLUSTRATION BY MARCIA HARTSOCK FIGURE 1. The cover test. (Top) Because chil- () or other material in the anterior dren with strabismus almost always use the chamber, cataract, vitreous opacity or retinal better eye, even small-angle strabismus in one disease. The most urgent diagnosis is retino- eye often indicates poor vision in the eye that blastoma (Figure 2), a malignancy most likely turns. (Center) The patient’s right eye centers arising from retinal germ cells. Because it may when the left eye is covered. (Bottom) It is likely that the right eye does not see as well as be hereditary, a family history of retinoblas- the left eye, especially if the right eye drifts toma or of enucleation is of special concern. again when the cover is removed. Although retinoblastoma is almost uniformly fatal without treatment, the cure rate is 90 per- cent or better when it is promptly recognized alternate eyes while the child looks at a toy, and treated,11 and many children can be effec- may help detect small deviations.9 False-posi- tively treated without enucleation. tive results are common when children change their fixation because of inattention. False-negative results occur when children are unable to refixate because of amblyopia. Exotropia is typically an intermittent devi- ation at first, beginning during the preschool years. As with all cases of strabismus, the deviating eye is at risk of amblyopia, although it is less likely with exotropia than with esotropia. Diagnosis is often a problem be- cause the deviation is most evident when the child looks at something far away. Unfortu- FIGURE 2. Leukocoria. Clinical photograph nately, most primary care offices usually do shows white pupillary reflex from the patient’s right eye, which contains a retinoblastoma. not have distant objects capable of captivat- The abnormal reflex, or leukocoria, is best visu- ing young childrens’ attention. Parents who alized using the direct ophthalmoscope in a relate that an eye turns out or that the child darkened room from a distance of 1 to 2 ft.

AUGUST 15, 2001 / VOLUME 64, NUMBER 4 www.aafp.org/afp AMERICAN FAMILY PHYSICIAN 625 Children who do not have a bright or symmetric red reflex (using an ophthalmoscope from a distance of 1 to 2 ft) should be referred to an ophthalmologist for urgent evaluation.

TESTING FOR THE RED REFLEX FIGURE 3. Conjunctivitis. Clinical photograph The most useful method of testing for the shows acute conjunctivitis. Infectious conjunc- red reflex is using the ophthalmoscope from a tivitis may have a viral or bacterial etiology. distance of 1 to 2 ft. Sometimes pigmented is usually associated fundi do not show the reflex well. The exami- with itching. nation is best performed in a well-darkened room. If the reflex is still poor, it may be help- intervals. Also at risk of glaucoma are children ful to dilate the with a drop of 1 percent with neurofibromatosis and Sturge-Weber tropicamide (Mydriacyl) or 2.5 percent syndrome. Pertinent features of congenital phenylephrine (Neo-synephrine). Children glaucoma (which differentiate it from the whose reflexes are still not bright or symmet- tearing seen in obstruction of the naso- ric should be referred urgently. lacrimal duct) include light sensitivity, in- creased corneal diameter, corneal cloudiness Glaucoma and, occasionally, conjunctival injection. Although glaucoma is usually considered a Glaucoma is likely to be bilateral. disease seen in older persons, it also can occur in children. Pressure inside the eye is too high, Ocular Inflammation damaging the . Adults with chronic Conjunctivitis is easily treated in most glaucoma typically have minimal symptoms. cases. Some children, however, do not re- Children, however, may develop discomfort, spond to topical antibiotics, and may have light sensitivity, tearing and gradual enlarge- persistent redness, discharge and discomfort ment or eventually, opacification of the (Figure 3). The most likely cause is probably cornea.12 Children who have had cataract viral conjunctivitis or (if surgery are especially at risk for glaucoma,13 the cornea is involved). Most cases are self- even in the absence of symptoms, and should limited, but conjunctivitis related to herpes be examined by an ophthalmologist at regular infection can become serious, especially if treated inappropriately with topical cortico- steroids. All resistant cases of conjunctivitis The Authors require a thorough slit-lamp examination, and it is probably best to avoid using topical JOHN W. SIMON, M.D., is professor and chair of the department and 14, 15 professor of pediatrics at Albany Medical College, Albany, NY. He received his medical medications that include steroids. degree and completed a residency in ophthalmology at Mount Sinai School of Medi- On occasion, topical antibiotics may be- cine of the City University of New York. Dr. Simon also served a fellowship in pediatric come toxic to the cornea, causing prolonged ophthalmology and strabismus at the Wills Eye Hospital, Philadelphia. redness and discomfort. Aminoglycosides are PAMELA KAW, M.D., is a fellow in pediatric ophthalmology and strabismus at Albany frequent offenders, especially after several days Medical College. She earned her medical degree and served an ophthalmology resi- dency at King George’s Medical College in India. of use. Preparations containing sulfonamides or neomycin are often allergenic. The most Address correspondence to John W. Simon, M.D., Albany Medical College/Lions Eye Institute, 35 Hackett Blvd., Albany, NY 12208. Reprints are not available from effective treatment in such cases is simply to the authors. discontinue all medications and observe.

626 AMERICAN FAMILY PHYSICIAN www.aafp.org/afp VOLUME 64, NUMBER 4 / AUGUST 15, 2001 Pediatric Eye Exam

On other occasions, a condition that appears to be conjunctivitis is actually a dif- ferent kind of ocular inflammation. Disorders of the ocular surface, such as dehydration of the cornea associated with poor eyelid closure or abrasion of the cornea due to misdirected lashes, may cause chronic redness and tear- ing. , or inflammation of the , cil- iary body or , may also cause light sensitivity, pain and loss of vision. Uveitis is called iritis if the inflammation is limited to the anterior chamber (Figure 4). The most common cause of iritis is juvenile rheumatoid arthritis. Unfortunately, iritis in children with juvenile rheumatoid arthritis typically has minimal symptoms and is diag- nosed on the basis of careful slit-lamp exam- FIGURE 4. Iritis. Operating room photograph ination. Hence, it is very important that shows conjunctival injection, irregular pupil children with iritis have periodic ophthalmo- and inflammatory debris in the anterior cham- logic examinations. ber of an eye with iritis.

Eye Trauma irrigation, preferably with saline or Ringer’s Children, especially boys, are at high risk of lactate solution, begun urgently and contin- eye injuries compared with the adult popula- ued until a neutral pH is achieved in the tion.16 Corneal abrasions and foreign bodies tears. The conjunctival cul de sacs should be (Figure 5) cause intense conjunctival redness thoroughly searched for any sequestered par- and sensitivity to light. Topical fluorescein ticles of caustic material. Subsequently, will stain the area of injury and a Wood’s cycloplegic drops and antibiotic ointment lamp may be helpful to visualize the stained should be prescribed, along with a pressure area. A foreign body may lodge under the patch or frequent use of preservative-free upper lid and cause corneal abrasions with artificial tears. each blink. Projectiles thrown by a lawn Children with shaken baby syndrome may mower or dislodged by banging two pieces of have retinal and vitreous hemorrhage, which metal together may penetrate and enter the eye with minimal external signs. Children with such injuries should be kept on their back with a protective shield over the eye if possible. Such foreign bodies are detected by detailed slit-lamp and examinations and often require imaging studies. Many chil- dren with eye trauma, therefore, require referral to an ophthalmologist, initially or in follow-up. Children with chemical injuries of the eye may present to the primary care office. Whether the offending agent is acid or alkali, FIGURE 5. Clinical photograph shows unusually the most important treatment is extensive large foreign body at 7:00 corneal periphery.

AUGUST 15, 2001 / VOLUME 64, NUMBER 4 www.aafp.org/afp AMERICAN FAMILY PHYSICIAN 627 Pediatric Eye Exam

can be detected on ophthalmologic examina- light, a Wood’s lamp, fluorescein strips and an tion. Consultation is indicated if suspicious ophthalmoscope—family physicians can injuries are seen. identify most important causes of vision loss.

Nystagmus The authors indicate that they do not have any con- Children with nystagmus may have disor- flicts of interest. Sources of funding: none reported. ders of the eye or the central nervous system. REFERENCES The most common cause is probably albinism, which sometimes causes only subtle 1. Fulton A. Screening preschool children to detect visual and ocular disorders [Editorial]. Arch Oph- hypopigmentation of the skin, hair and iri- thalmol 1992:110;1553-4. des. Ophthalmologic examination with the 2. Olitsky SE. Common ophthalmologic concerns in slit lamp demonstrates the iris pigment infants and children. Pediatr Clin North Am 1998; 45:993-1012. defect, as well as retinal hypopigmentation 3. Simons K. Preschool vision screening: rationale, and foveal hypoplasia. methodology and outcome. Surv Ophthalmol 1996; Other children with nystagmus may have 41(1):3-30. 4. How vision is tested. In: Simon JW, Calhoun JH, eds. bilateral optic nerve hypoplasia (a condition A child’s eyes: a guide to pediatric primary care. that may be associated with other distur- Gainesville, Fla.: Triad Publications, 1998:35-42. bances of the central nervous system in 5. Eye exam and vision screening in infants, children, and young adults. American Academy of Pediatrics patients with de Morsier’s syndrome), bilat- Committee on Practice and Ambulatory Medicine, eral media opacities or . Chil- Section on Ophthalmology. Pediatrics 1996:98(1): dren with hearing loss and poor vision should 153-7. 6. Visual development, amblyopia and sensory adap- be evaluated for Usher’s syndrome, which tations. In: Wright KW, ed. Pediatric ophthalmology includes pigmentosa. Subtle nystag- and strabismus. St. Louis: Mosby, 1995:119-26. mus may be detected by observing oscilla- 7. Rubin SE, Nelson LB. Amblyopia. Diagnosis and man- agement. Pediatr Clin North Am 1993;40:727-35. tions of the fundus during examination with 8. Exotropia. In: Wright KW, ed. Pediatric ophthalmol- an ophthalmoscope. ogy and strabismus. St. Louis: Mosby, 1995:195-202. 9. Testing for alignment. In: Simon JW, Calhoun JH, Systemic Conditions eds. A child’s eyes: a guide to pediatric primary care. Gainesville, Fla.: Triad Publications, 1998. Many other systemic disorders are associated 10. Mark FP. Pediatrics. In: Rhee DJ, Pyfer MF, eds. The with specific eye findings. For example, homo- Wills Eye manual. 3d ed. Philadelphia: Lippincott Williams & Wilkins, 1999:199-201. cystinuria and Marfan syndrome may cause 11. Shields CL, Shields JA. Recent developments in the dislocated lenses. Patients with Tay-Sachs dis- management of retinoblastoma. J Pediatr Ophthal- ease may have a “cherry-red” macula. Cysti- mol Strabismus 1999;36(1):8-18. 12. Walton DS. Glaucoma in infants and children. In: nosis may be associated with corneal and con- Nelson LB, Calhoun JH, Harley RD, eds. Pediatric junctival crystals, and a biopsy can be obtained ophthalmology. 3d ed. Philadelphia: Saunders, if necessary for diagnosis. The mucopolysac- 1991:258-70. 13. Russell-Eggitt I, Zamiri P. Review of aphakic glau- charidoses may cause corneal clouding. coma after surgery for . J Cata- ract Refract Surg 1997;23(suppl 1):664-8. Final Comment 14. BenEzra D. Current practice: diagnosis and treat- ment in primary health care. Allergy 1995;50(suppl Family physicians play a crucial role in the 21):30-8. management of eye problems in children. 15. Wallace DK, Steinkuller PG. Ocular medications in Vision screening is a vital part of routine care children. Clin Pediatr 1998;37:645-52. 16. Nelson LB, Wilson TW, Jeffers JB. Eye injuries in in children. Even with limited equipment—an childhood: demography, etiology, and prevention. interesting toy for fixation, an eye chart, a pen- Pediatrics 1989;84:438-41.

628 AMERICAN FAMILY PHYSICIAN www.aafp.org/afp VOLUME 64, NUMBER 4 / AUGUST 15, 2001