RGP insights

RGPs for the Pediatric Patient

BY LORETTA SZCZOTKA, OD, MS
AUGUST 1998

The most common indications for pediatric contact lens use include: monocular or bilateral aphakia, corneal trauma or scarring with secondary irregular astigmatism, high myopia, uncorrected hyperopia with accommodative esotropia and anisometropia. When an infant or toddler is uncooperative and difficult to examine, an initial instinct is to fit a soft or silicone contact lens because of quick lens tolerance. However, RGPs are my first choice for correcting any refractive condition in young children. In fact, most pediatric patients accept RGP lens wear as part of their daily routine after three to four weeks -- better than some adults.

The Power to Fine-Tune the Fit

The advantage of RGP lenses is the ability to custom order any powers or fitting parameters specific to the patient's needs instead of compromising to best fit hydrogel or silicone lenses, which are available in only predetermined base curves and powers. For instance, the power of a contact lens for an aphakic infant less than 18 months old should be overplussed by two to three diopters to allow for adequate near vision within the infant's visual range. Once the child grows and can tolerate bifocals, the distance power can be adjusted appropriately. As the eye continues to grow, fine base curve and diameter changes can be reordered in an RGP lens.

If the pediatric surgeon brings the child back for observation soon after surgery, placing the child under anesthesia is an efficient way to fit the first lens during the examination. Handheld slit lamps and keratometers are very beneficial if available, but you can perform the diagnostic fitting properly with a variety of diagnostic RGP lenses, fluorescein strips, a burton lamp or another type of handheld cobalt blue light, a retinoscope and handheld trial lenses.

Long-Term Corneal Health

Pediatric patients will most likely remain in contact lenses for the majority of their lives unless they eventually progress to secondary surgical procedures. Therefore, high oxygen transmissibility, especially in thick lens designs, is critical to assure long term corneal health (Fig. 1). Currently, only RGP polymers or silicone lenses (Silsoft, Bausch & Lomb) can offer oxygen levels that are high enough to prevent excessive edema and chronic endothelial damage. Silicone lenses, however, have significantly more disadvantages than RGPs, including excessive protein and lipid deposits and poor surface wetting.

FIG. 1:  Corneal Striae after removal of a thick hydrogel lens in young patient secondary to corneal edema.

Makes Economic Sense

RGP contact lenses are approximately one-third of the cost of a pediatric aphakic hydrogel or Silsoft lens, providing more affordable options for your practice and less of a financial burden on the parents when frequent loss, breakage and lens replacement occurs. And since RGP contact lenses are also less likely to deposit or be damaged from care and handling, they require fewer replacements than do soft or silicone contact lenses.

Although challenging, fitting a pediatric patient with RGP lenses is extremely rewarding when we provide the visual resources an infant needs to clearly recognize his parents, caregivers or siblings again or for the first time.

Dr. Szczotka is an assistant professor at Case Western Reserve University Dept. of Ophthalmology and Director of the Contact Lens Service at University Hospitals of Cleveland.