KEY POINTS

  • 1.

    Cataracts are inherited or sporadic; congenital or acquired; isolated or in a syndrome.

  • 2.

    Size, density, and location of lens opacity influence its visual significance.

  • 3.

    Timing of cataract surgery is important; earlier detection and surgery have better outcomes.

  • 4.

    Primary congenital glaucoma is the most common form of glaucoma in infants. It usually requires surgical treatment.

  • 5.

    Some forms of infantile glaucoma may be managed with topical antihypertensives but may also require surgery.

Congenital Cataract

Cataracts develop due to disturbances in the normal highly ordered cellular arrangement of the crystalline lens. Pediatric cataracts remain a significant cause of preventable blindness. However, the related vision loss can be greatly mitigated with prompt identification and treatment of significant lens opacities. In the United States, prevalence is estimated at 13.6 per 10,000 infants, with 3.0 to 4.5 per 10,000 being visually significant. The role of the neonatologist and pediatrician in early detection and prompt treatment cannot be overstated.

Presentation

History

Because congenital cataracts are often associated with genetic diseases or syndromes, a comprehensive history assists in diagnosis and management. Concerns about a white spot in the pupil, nystagmus, strabismus, asymmetric size of one eye relative to the other, photophobia, or visual inattentiveness should prompt referral. A detailed medical history includes documenting the onset of symptoms, such as whether prior exams documented a normal red reflex, birth weight, prematurity, evidence of maternal infection (especially TORCH infections [toxoplasmosis, other agents, rubella, cytomegalovirus, or herpes simplex], rash, or febrile illness during pregnancy), pertinent prenatal and perinatal history (i.e., radiation, alcohol, or drug exposure), maternal travel, history of ocular trauma, and corticosteroid therapy.

Family history is important. A complete ocular examination is needed within the first few weeks after birth in infants with a family history of childhood cataract, particularly if it is bilateral. Hereditary bilateral cataracts are often inherited in an autosomal dominant (AD) pattern with a high degree of penetrance. A history of consanguinity can help in identifying the risk of genetic disorders associated with congenital cataracts.

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.

Fig. 65.1, (A) Nuclear cataract in a 3-month-old infant. (B) Posterior subcapsular cataract in a 5-year old. (C) Cortical cataract viewed with retroillumination. ([B] From Thompson J et al: Cataracts. Prim Care. 42(3):409–23, 2015. © 2015 Copyright Elsevier BV. All rights reserved.)

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.

Table 65.1
Systemic Diseases Associated With Cataracts and/or Glaucoma
Condition Ocular Findings
METABOLIC
Galactosemia Cataracts (lamellar)
Fabry disease Cataracts (posterior subcapsular)
Hyperglycemia Cataracts
Mannosidosis Cataracts (posterior subcapsular)
Refsum disease Cataracts
Wilson disease Cataracts (sunflower)
Multiple sulfatase deficiency Cataracts
RENAL
Lowe syndrome Cataracts (multiple forms), glaucoma
Alport syndrome Cataracts (anterior lentiglobus)
MUSCULOSKELETAL
Myotonic dystrophy Cataracts (Christmas tree)
Chondrodysplasia punctate Cataracts
Stickler syndrome Cataracts, glaucoma
Albright hereditary osteodystrophy Cataracts
Robert syndrome Cataracts
Majewski syndrome Cataracts
DERMATOLOGIC
Cockayne syndrome Cataracts
Rothmund-Thomson syndrome Cataracts
Sturge-Weber syndrome Glaucoma
Juvenile xanthogranuloma Glaucoma
Neurofibromatosis Cataracts (PSC), glaucoma
Oculodermal melanocytosis Glaucoma
OTHER
Rubinstein-Taybi syndrome Cataracts, glaucoma
Smith-Lemli-Opitz syndrome Cataracts
Cerebro-oculo-facial-skeletal syndrome Cataracts
Kabuki syndrome Glaucoma
CHROMOSOMAL ABNORMALITIES
Trisomy 13 Cataracts, glaucoma
Trisomy 18 Cataracts
Trisomy 21 Cataracts
Turner syndrome Glaucoma
PSC, Posterior subcapsular cataract.

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

Laboratory Investigations and Tests

Please see the online version for details. Most congenital cataracts are idiopathic, especially when unilateral. Up to 86% of unilateral and 68% of bilateral cataracts have no discernable cause. There may be associated eye anomalies in up to one-fourth of eyes with cataracts.

TORCH screening should be done in infants with maternal TORCH infections or if microcephaly, thrombocytopenia, and hepatomegaly are present. Bilateral cataracts, hypotonia, failure to thrive, and developmental delay may indicate a possibility of a metabolic disorder. Next-generation sequencing may be useful. A genetics consultation is important for these infants.

Examination Under Anesthesia

An exam under anesthesia (EUA) is recommended with preparation for possible cataract removal, with measurement of intraocular pressure, corneal diameter, a complete eye examination with refraction, and retinoscopy. Determination of corneal curvature and globe axial length helps in surgical planning, intraocular lens power calculation, and prognostication. If there is poor view to the posterior pole, B-scan ultrasonography is done to make sure that there is no associated retinal pathology or PFV prior to proceeding with surgery.

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