Cataract and Glaucoma

Presentation

Examination

For infants with bilateral cataracts, parents and caregivers can provide information on visual interest. In neonates, the significance of a cataract is determined primarily by examination. Later, visual fixation, following faces, and reaching for objects are important milestones. For monocular cataracts, squinting, crossing, or wandering of an eye, a face turn, or opposition to blocking vision in one eye can allude to poor vision in the setting of lens opacity.

The Bruckner Red Reflex Test can be used to detect and determine the density of a lens opacity. Both eyes are viewed using a direct ophthalmoscope at a distance of approximately 3 feet to compare the red reflexes. The light reflex is normally symmetric in both eyes.

Infants with uni- or bilateral cataracts can develop nystagmus due to poor vision. Those with bilateral, dense cataracts often develop nystagmus by 3 months of age, which is when the fixation reflex normally develops.

Congenital cataracts can be classified based on morphology, location, laterality, and/or etiology ( Fig. 65.1 ). Although a detailed description of each type of cataract is beyond the scope of this text, the neonatologist must remember several characteristics that make cataracts more visually significant and thus amblyogenic: large and dense opacities, central and posterior location, unilaterality, or association with a persistent fetal vasculature (PFV). Cataract type is a critical determinate of outcome and can assist in narrowing a genetic diagnosis.

AD-inherited bilateral nuclear cataracts are usually an isolated finding (see Fig. 65.1 ); these can be variable in density and visual significance and are often visible with a simple bedside penlight exam as a centrally located, white opacification obscuring the visual axis. In a recent large, US-based cataract registry, family history was present in 18% of 994 children.

In contrast, PFV cataracts are typically unilateral and the eye is often microphthalmic. A fibrovascular stalk may connect the posterior lens capsule to the optic nerve and can cause a tractional retinal detachment if it extends to the retina. Angle closure glaucoma may also occur if the retrolenticular membrane contracts. Aphakic glaucoma commonly occurs after removal of a PFV cataract. Visual outcomes are generally quite poor.

Many hereditary cataracts present at birth, although many worsen with age and may be detected only in later years. Cataracts may be the first, or a later, presenting sign of a systemic disorder. Lamellar or zonular cataracts are usually inherited in an AD fashion and are among the most common type of inherited childhood cataracts (see Fig. 65.1 ). Usually bilateral, the opacities are not visually significant unless they progress to involve the lens cortex or nucleus. Table 65.1 summarizes inherited cataracts related to systemic disorders. Physical examination can help tailor investigations to identify syndromic associations.

In-utero maternal infections, trauma, and exposure to therapeutic agents (i.e., corticosteroids or radiation) are noninherited causes of congenital cataracts. Lens opacities tend to develop later in neonates exposed to steroids or radiation. Traumatic injury to the lens has been reported to occur in infants treated for retinopathy of prematurity.

Workup and Management