Peripheral Refraction of Two Myopia Control Contact Lens Models in a Young Myopic Population

Abstract

Peripheral refraction can lead to the development of myopia. The aim of this study was to compare relative peripheral refraction (RPR) in the same cohort of uncorrected (WCL) and corrected eyes with two different soft contact lenses (CL) designed for myopia control, and to analyze RPR depending on the patient’s refraction. A total of 228 myopic eyes (114 healthy adult subjects) (−0.25 D to −10.00 D) were included. Open-field autorefraction was used to measure on- and off- axis refractions when uncorrected and corrected with the two CLs (dual focus (DF) and extended depth of focus (EDOF)). The RPR was measured every 10° out to 30° in a temporal-nasal orientation and analyzed as a component of the power vector (M). The average RPR for all subjects was hyperopic when WCL and when corrected with EDOF CL design, but changed to a myopic RPR when corrected with DF design. Significant differences were found between RPR curves with both CLs in all the eccentricities (Bonferroni correction p < 0.008, except 10°N). An incremental relationship between relative peripheral refraction at 30 degrees and myopia level was found. It is concluded that the two CLs work differently at the periphery in order to achieve myopia control.

Peripheral refraction under different levels of illuminance

“…found that eyes with low myopia had relative peripheral hyperopia only at 30° in the TVF and NVF, whereas those with moderate and high myopia had relative peripheral hyperopia at all eccentricities. Similar findings were reported by Marcellán et al 34 . They observed a statistically significant, increasing linear trend in RPR measured at 30° eccentricities (nasal and temporal) with respect to the degree of myopia.…”

“…7,[31][32][33] We found asymmetry between nasal and temporal eccentricities at the same peripheral location for each lighting condition, although the result was not significant (all p > 0.89). Marcellán et al 34 recently reported that the RPR was less hyperopic for the TVF than the NVF, but again, the difference was not statistically significant. Mutti et al 7 also found a hyperopic (although asymmetric) increase in the temporal and nasal retinas of Caucasian patients.…”