Article

PEDIATRIC AND TEEN CL CARE

CONTACT LENSES FOR MYOPIA MANAGEMENT IN CHILDREN

It is estimated that by 2050, half of the world population will be myopic; myopia is being diagnosed in many countries at increasingly younger ages (Holden et al, 2015). Children who develop myopia at a younger age progress more quickly and to higher amounts of myopia. Increased severity of myopia is associated with an increased risk of pathology (Flitcroft, 2012).

Because myopic children are at greater risk for developing high myopia, it is important to slow myopia progression as early as possible. This article discusses contact lens options for slowing this progression.

Contact Lens Options for Slowing Myopia Progression

Orthokeratology (OK) utilizes specially designed rigid contact lenses to reshape the corneal contour to temporarily modify or eliminate refractive error. Currently, the most common application for OK is the reduction of myopia; however, other designs target reduction of astigmatism, hyperopia, and even presbyopia. Investigations of OK contact lenses have reported that they slow the growth of the eye by 43% on average (Charm and Cho, 2013; Chen et al, 2013; Cho and Cheung, 2012).

Soft bifocal contact lenses that have a center-distance design have been investigated for myopia management. On average, soft bifocal contact lenses slow myopia progression by 46% (Lam et al, 2014; Walline et al, 2013).

Both OK and soft lenses are thought to slow myopia progression by providing peripheral myopic blur, which is a putative cue to decrease eye growth (Ticak and Walline, 2013).

GP lenses effectively correct high amounts of myopia and astigmatism. Bifocal GP lenses may be better suited for myopia management in children who have high amounts of refractive error and are difficult to correct with OK or soft bifocal lenses (Liu, 2017). Many corneal and scleral GP lenses are commercially available in center-distance bifocal designs. Hybrid lenses also are available with these parameters.

Reverse Geometry Scleral for Anisometropia and Myopia

Take for example a 17-year-old male who has high myopia and anisometropia. His manifest refraction was –4.75 –3.00 x 009 in the right eye and –10.00 –2.50 x 177 in the left eye, which resulted in 20/20 and 20/25 vision in each eye, respectively. The patient stated that he had previously tried soft toric lenses but had experienced unacceptable vision due to on-eye instability of the lenses. He had also tried corneal GP lenses but could not achieve comfortable wear.

He was successfully fitted into reverse geometry scleral GP lenses. Because the reverse geometry design allowed for flatter base curves, a less minus scleral lens prescription was finalized (38.00D base curve with a –2.12D power in the right eye and 34.00D base curve with a –5.50D power in the left eye) (Figure 1). Additionally, a +3.50D center-distance multifocal add power was incorporated onto the front surface to manage the patient’s progressive high myopia. CLS

Figure 1. Specialty contact lenses can be fitted in pediatric patients for myopia management. Oblate scleral lenses can be designed for these patients to decrease the high-minus lens prescription.

For references, please visit www.clspectrum.com/references and click on document #281.