contact lens case reports
Managing Aphakic
Infants
BY PATRICK J. CAROLINE, FAAO, & MARK P. ANDRÉ, FAAO
According to statistics, congenital and early onset cataracts account for roughly 10 percent to 30 percent of blindness in infants today.
In a study of 96 children presenting with a primary diagnosis of cataracts, researchers found the the following factors responsible for the lens opacities: intrauterine infection (36 percent), unknown causes (31 percent), heredity (23 percent) and various syndromes and metabolic disorders (10 percent).
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Figure 1. Contact lens fitting under
general anesthesia. |
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Dealing with Infant Cataracts
Improved surgical techniques, safer anesthesia and improved post-surgical optical correction have greatly increased the visual prognosis in congenital aphakia. However, early detection and prompt treatment (cataract removal) are essential for a good visual and binocular outcome.
Studies have shown that when bilateral cataracts are removed before eight weeks, normal visual development may be possible. In the case of unilateral cataracts, early treatment before six weeks provides the greatest opportunity for an improved visual outcome.
Surveying the Options
After cataract removal, you have three options available for optically correcting aphakia: intraocular lenses (IOLs), contact lenses and spectacle lenses. But because of the rapid growth of the eye before the age of two, IOLs are rarely used to manage infantile aphakia, and spectacle lenses present some unique challenges secondary to the high plus correc tion and the child's underdeveloped nose and bridge.
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Figure 2. A look at the Silsoft lens on the patient's left
eye. |
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Contact lenses have proven quite successful in managing aphakic infants. We have found significant advantages to using the Bausch & Lomb SilSoft contact lens (Table 1) on our aphakic patients. One of the primary advantages of this contact lens is its high Dk (340), which allows our pediatric patients to safely wear it on a continuous wear basis.
Case in Point
DM was born with an idiopathic, unilateral cataract OS, which a surgeon successfully removed surgically 10 days after she was born. We fit her with a SilSoft lens (Figures 1 & 2). Over the past six years our patient has tolerated the lens extremely well with only a minimal number of lost lenses. Today, her visual acuities are 20/20 OD and 20/30 OS.
The ultimate success of correcting aphakia depends on a number of factors including the child's ability to wear the lenses full time, centration of the high plus lens over the pupil, minimal disruption of the child's wearing schedule secondary to inadequate parent compliance or lost lenses, appropriate lens powers at the various stages of development, success of the amblyopia therapy and post-surgical ocular and systemic health.
TABLE 1 B&L SilSoft Super Plus Pediatric |
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BASE CURVES | POWERS | DIAMETER |
7.5mm, 7.7mm, 7.9mm | +23.00 to +32.00 in 3.00D steps | 11.3mm |
Patrick Caroline is an associate professor of optometry at Pacific University and is an assistant professor of ophthalmology at the Oregon Health Sciences University.
Mark André is director of contact lens services at the Oregon Health Sciences University and is an adjunct assistant professor of optometry at Pacific University.