High corneal astigmatism (≥ 2.50D) presents a contact lens fitting challenge in pediatric patients. GP lenses can correct large amounts of astigmatism and offer sharp, stable optics, ensuring good quality vision in pediatric patients who have high astigmatism. This article reviews the GP lens options for correcting high astigmatism in children.
Corneal GP lenses are a great option for visual correction of astigmatic kids. Back-surface spherical corneal GP lenses can work for borderline high-astigmatic corrections, such as those patients who have less than 3.00D of corneal astigmatism or those who have centrally localized (not limbus-to-limbus) astigmatism. Nevertheless, prescribing a spherical-back-surface corneal GP for a highly astigmatic eye may result in a suboptimal fit. Fitting issues that may arise include decentration and induced flare from misaligned optics, corneal desiccation from excessive peripheral clearance and lens rocking, and/or flexure-induced fluctuations in vision (Bennett et al, 2014).
When prescribing corneal GP lenses for high astigmatism, a bitoric design is ideal in most cases. Bitoric corneal GP lenses center better on highly astigmatic eyes, thereby avoiding a key drawback of spherical-back-surface designs.
Regardless of the lens design, the relatively small diameter and rigidity of corneal GP contact lenses make it easy for children to apply and remove them.
Scleral lenses are also a good choice for highly astigmatic children. Because they completely vault over the cornea, scleral lenses can correct high amounts of astigmatism.
The large diameter of scleral lenses also enables good centration and stable optics. Other advantages include greater comfort and decreased likelihood of being dislodged from the eye. These benefits make scleral lenses ideal for active, highly astigmatic kids.
Consider, for example, a hyperopic astigmatic teenage track athlete who has a spectacle prescription of +7.00 –4.50 x 180 in both eyes with corneal astigmatism that extends limbus to limbus (Figure 1). Initially, bitoric corneal GP lenses were fitted that gave her 20/20 vision; however, the dusty sports environment made it difficult for her to wear these lenses. Subsequently, a soft custom toric lens was fitted, but rotational instability gave her fluctuating, unacceptable vision. She was then refit into scleral contact lenses, which corrected her to 20/20 and protected her eyes from dust (Figure 2).
GP contact lenses are a great vision correction option for children who have high astigmatism. Compared to spectacles and soft contact lenses, GP optics provide sharper and more stable vision. With such clear benefits, offering GP lenses to your astigmatic pediatric patients is a cinch. CLS
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