Searching, roving movements of the eyes starting at about 4 to 8 weeks of age. Poor pupillary constriction to light in infants ≥31 weeks gestation is a key finding. Inability to fix or follow large, bright objects after 4 months of corrected age.

Etiologies with an Abnormal Ocular Examination

• Severe ocular disease or malformation.

• Retinoblastoma: up to 40% of cases may have bilateral tumors. See 8.1, Leukocoria.

• ROP. See 8.2, Retinopathy of Prematurity.

• Dense bilateral cataracts in children >8 weeks of age. See 8.12, Pediatric Cataract.

• Aniridia and other severe anterior segment dysgenesis. See 8.14, Developmental Anterior Segment and Lens Anomalies/Dysgenesis.

• Albinism: Iris transillumination defects and foveal hypoplasia. See 13.8, Albinism.

  NOTE Ocular abnormalities in patients with albinism and aniridia may be subtle and difficult to assess during an office evaluation.

• Optic nerve hypoplasia: Small optic discs can be difficult to detect when bilateral. When present, a “double-ring” sign (a pigmented ring at the inner and outer edge of a peripapillary scleral ring) is diagnostic. If unilateral, may be seen with strabismus, a relative afferent pupillary  defect, and unilateral poor fixation instead of searching nystagmus. Usually idiopathic.

  NOTE Bilateral optic nerve hypoplasia is occasionally associated with septo-optic dysplasia (formerly known as de Morsier syndrome). In contrast, unilateral optic nerve hypoplasia is only rarely associated with this syndrome. Septo-optic dysplasia includes midline abnormalities of the brain as well as growth, thyroid, and other trophic hormone deficiencies. Growth retardation, seizures as a result of hypoglycemia, and diabetes insipidus may develop. If bilateral optic nerve hypoplasia is present, obtain an MRI with attention to the hypothalamic–pituitary area. If unilateral optic nerve hypoplasia is present, imaging studies may be considered as clinically relevant.

• Congenital optic atrophy: Rare. Pale, normal-sized optic disc, often associated with intellectual disability or cerebral palsy. Normal electroretinogram (ERG). Autosomal recessive or sporadic.

• Shaken baby syndrome: Multilayered retinal hemorrhages secondary to trauma, often associated with subdural/subarachnoid hemorrhage. See 3.17, Abusive Head Trauma/Shaken Baby Syndrome.

• Extreme refractive error: Diagnosed on cycloplegic refraction.

• Congenital motor nystagmus: Patients with this condition usually have a mild visual deficit (20/60 or better). Binocular conjugate horizontal nystagmus. More than one type of nystagmus may be present, including jerk, pendular, circular, or elliptical. Patients may adopt a face turn to maximize gaze in the direction of the null point. No associated CNS abnormalities exist.

Etiologies with a Normal Ocular Examination

• Leber congenital amaurosis: Rod–cone disorder. May have a normal-appearing fundus initially, but by childhood ocular examination reveals narrowing of retinal blood vessels, optic disc pallor, and pigmentary changes. ERG is markedly abnormal or flat which establishes the diagnosis. Autosomal recessive.

• Congenital stationary night blindness: Visual acuity may be close to normal, nystagmus less common, associated with myopia. ERG is abnormal. Autosomal dominant, recessive, and X-linked forms exist. Often have paradoxical pupillary response (pupillary constriction in dim light after exposure to bright light). Retinal pigmentary abnormalities are seen in some types of congenital stationary night blindness.

• Achromatopsia (rod monochromatism): Vision is in the 20/200 range. Marked photophobia. Pupils react normally to light but may have paradoxical pupillary response. Normal fundus, but photopic ERG is markedly attenuated. Absence of response to flicker light stimulus (25 Hz) is diagnostic. Scotopic ERG is normal.

• Cortical visual impairment: One of the most common causes of visual impairment in children from developed countries. Vision is variable. Although the ocular examination is normal, there is an underlying neurologic deficiency causing decreased visual responses.

• Diffuse cerebral dysfunction: Infants do not respond to sound or touch and are neurologically abnormal. Vision may slowly improve with time.

• Delayed maturation of the visual system: Normal response to sound and touch and neurologically normal. The ERG is normal, and vision usually develops between 4 and 12 months of age. More common in patients with albinism (may have nystagmus at presentation).

1. History: Premature? Normal development and growth? Maternal infection, diabetes, or drug use during pregnancy? Seizures or other neurologic deficits? Family history of eye disease?

2. Evaluate the infant’s ability to fixate on an object and follow it.

3. Pupillary examination, noting both equality and briskness.

4. Look carefully for nystagmus (see 10.21, Nystagmus).

5. Examination of the anterior segment; check especially for iris transillumination defects.

6. Dilated retinal and optic nerve evaluation.

7. Cycloplegic refraction.

8. ERG and genetic testing if Leber congenital amaurosis or a retinal dystrophy is suspected.

9. Consider a CT scan or MRI of the brain in cases with other focal neurologic signs, seizures, failure to thrive, developmental delay, optic nerve hypoplasia, or neurologically localizing nystagmus (e.g., seesaw, vertical, gaze paretic, vestibular). If optic atrophy,  either unilateral or bilateral, is present, obtain an MRI to evaluate for a glioma of the optic nerve or chiasm and craniopharyngioma.

10. Optical coherence tomography (OCT) may be helpful to further evaluate optic nerve anomalies.

11. Consider eye movement recordings to evaluate the nystagmus wave form, if available.

1. Correct refractive errors and treat known or suspected amblyopia. See 8.5, Amblyopia.

2. Parental counseling is necessary in all of these conditions with respect to the infant’s visual potential and the likelihood of visual problems in siblings.

3. Referral to educational services for the visually handicapped or blind may be helpful.

4. Provide genetic counseling and testing, if available.

5. If neurologic or endocrine abnormalities are found or suspected, the child should be referred to a pediatrician for appropriate workup and management.