Bilateral optic atrophy in childhood. I

Etiology and clinical profile of childhood optic nerve atrophy at a tertiary eye care center in South India

Background:

Optic nerve atrophy is an important ophthalmological sign that may be associated with serious systemic conditions having a significant bearing on the overall morbidity of the child. Studies specific to etiology of childhood optic atrophy are scarce, this being the first such study from India to the best of our knowledge.

Aim:

The aim was to analyze the clinical features and etiology of diagnosed cases of optic nerve atrophy in children <16 years of age.

Materials and Methods:

Retrospective review of records of children diagnosed with optic nerve atrophy between the ages of 0 and 16 years from 2006 to 2011.

Results:

A total of 324 children (583 eyes) were identified. Among these 160 (49%) presented with defective vision, 71 (22%) with strabismus, 18 (6%) with only nystagmus. Rest had a combination of two or three of the above symptoms. Sixty-five patients (20%) had a unilateral affection. Hypoxic ischemic encephalopathy seen in 133 patients (41%) was the most frequent cause of childhood optic atrophy, followed by idiopathic in 98 (30%), hydrocephalus in 24 (7%), compressive etiology in 18 (5%), infective in 19 (6%), congenital in 6 (2%), inflammatory in 5 (2%) patients, respectively.

Conclusion:

Hypoxic ischemic encephalopathy appears to be the most common cause of optic atrophy in children in this series. The most common presenting complaint was defective vision.

Dissociated visual development: electrodiagnostic studies in infants who are 'slow to see'

Four infants were studied who failed to show any visual interest or following responses in the first three months of life. Although no definite ocular abnormalities were found at the time of presentation, both the parents and their medical advisers initially had serious concerns about the infants' visual prognosis. Initial electroretinograms (ERG) were found to be unequivocally normal, but three of the infants showed absent or impaired cortical visual evoked responses (VER). The fourth infant had an initial VER which was immature. Subsequently, all the infants showed increasing visual responsiveness from three to four months of age and all now have visual behaviour and general development appropriate to their ages. The VERs were repeated after four months of age and all showed normal responses. It is concluded that poor or even absent VER responses in early infancy may not always indicate a poor prognosis for vision. The possible mechanisms of this visual maturational lag are discussed.