Christopher M. Fecarotta
• Any opacity of the crystalline lens is called a cataract
• Can be congenital or developmental
• Isolated or associated with anterior ocular segment dysgenesis
• With or without systemic disease
• Multitude of morphology including anterior polar, lamellar, nuclear, posterior lenticonus, persistent fetal circulation with vascularized plaque, anterior lenticonus, pulverulent, cerulean, sutural, total, and others
– Known cause or inherited in approximately 60–70% of cases
In the US, the incidence is estimated to be 1.2–6 cases per 10, 000.
• Intrauterine infections
• Metabolic conditions
• Family history
• Trauma including birth trauma
• Some genetic syndromes
• The most common mode of transmission is autosomal dominant with variable penetrance.
• Multiple genes are identified that, when mutated, can result in cataracts. Multiple additional loci are known without mapped genes.
• Can also be autosomal recessive or X-linked recessive
• Maternal vaccination can prevent certain infections that cause cataracts in newborns, but otherwise prevention is limited.
• Prenatal ultrasound is unreliable.
• Genetic testing not currently useful due to large number of possible genes but genetic counseling may be helpful in family planning.
• Prevention of visual loss by early identification. All children born to a parent with known heritable cataract should be examined by an eye doctor in the first 2 days of life and followed serially thereafter.
Depends on the cause, but generally involves a loss of lens clarity in a specific region of the lens based on the time of intrauterine insult or the specific mutated gene.
• Most commonly idiopathic
• Most common known cause is genetic and many isolated otherwise idiopathic cataracts may prove later to be heritable
• Other etiologies: Chronic corticosteroid use, genetic syndromes, metabolic disorders, and intrauterine infections are the most common
COMMONLY ASSOCIATED CONDITIONS
• Intrauterine infection
– Rubella, varicella, toxoplasmosis, herpes simplex, bacterial, or fungal endophthalmitis, cytomegalovirus.
• Metabolic disorders
– Galactosemia, hypocalcemia, hypoglycemia, diabetes mellitus, mannosidosis, hyperferritinemia
– Trisomy 21, Turner syndrome, trisomy 13, trisomy 18, Cri du chat syndrome and many others
• Renal disease
– Lowe syndrome, Alport syndrome, Hallermann-Streiff-Francois syndrome
• Drug induced
– Corticosteroids, chlorpromazine
– Microphthalmia, aniridia, retinitis pigmentosa, persistent fetal vasculature, retinopathy of prematurity, endophthalmitis
• History of parents seeing an abnormal pupillary reflex (leukokoria) directly or in a photograph
• History of condition known to be associated with pediatric cataracts
• Cataract alone does not cause an afferent pupillary defect.
• Visual assessment of each eye individually
• Cycloplegic refraction
• Slit-lamp biomicroscopy
• Determination of the cataract’s visual significance by quality of retinoscopy reflex, fundus view, and when possible, visual acuity
• Examination of the optic nerve and retina
• If unable to visualize the retina, B-scan ultrasonography is necessary to rule out persistent fetal vasculature, retinal detachment, and retinoblastoma
• The size, location, density, and visual acuity are all considered in determination of therapy
DIAGNOSTIC TESTS & INTERPRETATION
Initial lab tests
• TORCH titers in bilateral congenital cases with systemic indicators
• Consider galactokinase levels to rule out galactosemia in bilateral cases
• Other tests as suggested by systemic or ocular examination
Follow-up & special considerations
Referral to geneticist if a systemic syndrome is suspected
– Retinoblastoma, toxocariasis, Coats disease, persistent fetal vasculature, retinal astrocytoma, retinochoroidal coloboma, retinal detachment, myelinated nerve fibers, uveitis, incontinentia pigmenti, toxoplasmosis
• If the cataract is central but less than 3 mm, occlusion therapy over the opposite eye combined with mydriatic drops (2.5% phenylephrine) can be an effective therapy.
• A unilateral punctuate cataract often requires careful monitoring only.
• If systemic disease is uncovered, referral to the appropriate pediatric subspecialist should be made.
• Referral to geneticist if a systemic syndrome is suspected
• Postoperative refractive correction and occlusion therapy are essential for visual rehabilitation.
• Larger, denser central cataracts that are more visually significant require surgery
• Pediatric cataracts are usually removed using mechanical aspiration techniques rather than phacoemulsification.
• Primary posterior capsulotomy and anterior vitrectomy are indicated in any child not old enough to perform postoperative YAG laser.
• Placing the IOL in the capsular bag is best, but if that is not possible then sulcus fixation is acceptable.
• Use of intraocular lens implants in children under 1–2 years of age is controversial.
• Contact lenses (usually silicone elastomer and rigid gas permeable lenses) or glasses in unilateral or bilateral cases are acceptable alternatives to IOL implantation. Contact lens is the standard of care for children <1 year old.
Amblyopia therapy is carried out in the standard manner depending on the density of visual loss.
The Pediatric Glaucoma and Cataract Family Association: www.pgcfa.org.
Depends on the presence of concomitant ocular disease, age of onset, length of time of visual axis occlusion, and density of amblyopia.
• Most common complications are posterior capsule/anterior vitreous face opacification and aphakic/pseudophakic glaucoma.
• Other complications include hyphema, iris incarceration in the incision, pupillary distortion, vitreous hemorrhage, retinal hemorrhages, retinal detachment, intraocular lens subluxation, and endophthalmitis.
• Later complications including aphakic or pseudophakic glaucoma can arise years later in up to 30% of cases. Highest risk if microphthalmia, nuclear cataract or persistent fetal circulation. Average time of onset is 8 years postoperatively. Minimum annual IOP measurement even if sedation/anesthesia required
• Toxic anterior segment syndrome (TASS) causing postoperative corneal edema must be prevented with careful instrument and solution sterilization.
• Taylor D, Hoyt CS. Pediatric ophthalmology and strabismus, 3rd ed. Philadelphia, PA: Elsevier Limited, 2005:441–457.
• Wright KW. Lens abnormalities: Chapter 27 in pediatric ophthalmology and strabismus. In: Wright KW, Spiegel PH (eds), 2nd ed. New York: Springer-Verlag, 2003:450–480.
• Tesser RA, Hess DB, Buckly EG. Pediatric cataracts and lens anomalies, Chapter 13 in Harley’s Pediatric Ophthalmology. In: Nelson LB, Olitsky SE (eds), 5th ed. Philadelphia: Lippincott Williams & Wilkins, 2005:255–284.
• Parks MM, Johnson DA, Reed GW. Long-term visual results and complications in children with aphakia. A function of cataract type. Ophthalmology 1993;100(6):826–840; disc p 840–1.
• Awner S, Buckley EG, DeVaro JM, et al. Unilateral pseudophakia in children under 4 years. J Pediatr Ophthalmol Strabismus 1996;33(4):230–236.
• Huang Y, Dai Y, Wu X, et al. Toxic anterior segment syndrome after pediatric cataract surgery. J AAPOS 2010;14(5):444–446.
• 366.00 Nonsenile cataract, unspecified
• 743.30 Congenital cataract, unspecified
• 743.39 Other congenital cataract and lens anomalies
• Congenital and pediatric cataracts can be caused by ocular developmental dysgenesis, intrauterine infections, metabolic syndromes, gene mutation, or as part of a multisystem syndrome.
• Work-up for systemic disease or referral to a pediatric genetics specialist should be considered as suggested by ocular and systemic evaluation.
• Determination of a cataract being visually significant determines necessity for and method of treatment.
• After cataract surgery, patients should be followed closely for development of amblyopia, glaucoma, and other complications.