Neuro-ophthalmic manifestations of prematurity

Abstract

Increasing rates of preterm births coupled with better survival of these infants have resulted in higher prevalence of systemic and ocular complications associated with prematurity. In addition to retinopathy of prematurity, infants who are born preterm may suffer from severe visual impairment as a result of hypoxic ischemic encephalopathy, hypoglycemia, and other metabolic imbalances. The effect of these processes on the anterior visual pathway may result in optic atrophy, optic nerve hypoplasia or optic disc cupping and affection of the posterior visual pathway leads to cortical visual impairment (CVI). Other ocular associations include strabismus, nystagmus, and ocular motor abnormalities such as tonic down gaze and defective saccades and pursuits. Cortical and subcortical involvement also manifests as defects in functional vision and these have not yet been completely understood. Children with CVI may have visual field defects, photophobia, defective visual processing, and deficient color vision. Since most of these children also suffer from additional systemic disabilities, evaluation, and management remains a challenge. However, early diagnosis and initiation of rehabilitation therapy can prove to be of significant benefit in these children.

Figure 1

T1-weighted magnetic resonance imaging showing thinning of the corpus callosum in a child with hypoxic ischemic encephalopathy

Figure 2

(a and b) Optic disc pictures of a 13-year-old girl referred with a diagnosis of juvenile glaucoma. The discs show large cups with mild to a moderate pallor. (c and d) Visual field defects not corresponding to the appearance of the optic discs. (e) T1-weighted magnetic resonance imaging showing periventricular changes due to hypoxic-ischemic encephalopathy

Figure 3

A child with microcephaly and congenital exotropia (a) with cystic encephalomalacia due to hypoxic-ischemic encephalopathy as seen on the T2-weighted magnetic resonance imaging (b)