Rubella, also called German measles, is a communicable viral illness that typically begins with mild fever and lymphadenopathy, followed by a characteristic brief appearance of a generalized, erythematous, maculopapular rash. Postnatal rubella is generally a mild, self-limited, and relatively benign infection. However, maternal rubella infection during the first trimester of pregnancy can be devastating and can result in miscarriage or in the birth of an infant who has a constellation of congenital anomalies referred to as congenital rubella syndrome. Prior to the introduction of the rubella vaccine, rubella was endemic worldwide. Since the introduction of the vaccine in 1969, rubella has become rare in North America and in many developed countries (Cordier et al, 2012).
Cataracts, congenital heart defects, and sensorineural deafness are the classic triad of congenital rubella syndrome (Leung et al, 2019). Ophthalmic abnormalities, including cataracts, pigmentary retinopathy, infantile glaucoma, corneal clouding, chorioretinitis, iris hypoplasia, lacrimal drainage anomalies, and microphthalmia, occur in approximately 40% of cases. Cataracts occur in approximately 25% of these children and are bilateral in approximately 50% of cases (Best, 2007). Congenital rubella syndrome is the most common cause of congenital cataracts in developing countries (Fang et al, 2013).
Dense cataracts obscuring the visual axis produce deprivation amblyopia and require prompt surgical intervention and proper subsequent visual correction (Zetterström et al, 2005). Contact lenses are a good option for managing refractive error following extraction of congenital cataracts (Lindsay and Chi, 2010).
A Case for Corneo-Sclerals
Take for example a Hispanic female who has congenital rubella syndrome and was adopted from Latin America by a U.S. military family at the age of 5 years. This young patient had a medical history of the classic findings of congenital rubella syndrome including cataracts, cardiac problems, and deafness. She underwent bilateral cataract surgery before 1 month of age and was left aphakic. Additionally, she had a history of mental and psychomotor retardation, pigmentary retinopathy, and microphthalmia.
At age 8 years, she formed a habit of repetitive facial and eye rubbing, which caused bilateral central corneal abrasions and frequent dislodgement of her soft contact lenses. Scleral contact lenses have good on-eye stability and can protect the cornea from mechanical shearing action (Rathi et al, 2012). Thus, corneo-scleral lenses were fitted to correct for aphakia and to protect her corneas from further mechanical injury (Figure 1).
Figure 1. Corneo-scleral lenses corrected aphakia and prevented further mechanical injury to the cornea in this patient.
Watch for Mechanical Injury
Managing patients who have congenital rubella syndrome can be challenging due to the wide range of ophthalmic and systemic disorders. Aphakia from congenital cataracts is common in those affected by fetal viral disease and can be well corrected through contact lenses.
Consider corneo-scleral lenses when a child rubs his or her eyes, creating mechanical injury to the cornea and continual dislodgment of corrective lenses. Corneo-scleral lenses have the benefit of good on-eye stability and are able to protect the eye from mechanical harm. CLS
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