We compared the efficacy of controlling the annual increase in axial length (AL) in myopic Caucasian children based on two parameters: the back optic zone diameter (BOZD) of the orthokeratology (OK) lens and plus power ring diameter (PPRD) or mid-peripheral annular ring of corneal steepening. Data from 71 myopic patients (mean age, 13.34 ± 1.38 years; range, 10–15 years; 64% male) corrected with different BOZD OK lenses (DRL, Precilens) were collected retrospectively from a Spanish optometric clinic. The sample was divided into groups with BOZDs above or below 5.00 mm and the induced PPRD above or below 4.5 mm, and the relation to AL and refractive progression at 12 months was analyzed. Three subgroups were analyzed, i.e., plus power ring (PPR) inside, outside, or matching the pupil. The mean baseline myopia was −3.11 ± 1.46 D and the AL 24.65 ± 0.88 mm. Significant (p < 0.001) differences were found after 12 months of treatment in the refractive error and AL for the BOZD and PPRD. AL changes in subjects with smaller BOZDs decreased significantly regarding larger diameters (0.09 ± 0.12 and 0.15 ± 0.11 mm, respectively); in subjects with a horizontal sector of PPRD falling inside the pupil, the AL increased less (p = 0.035) than matching or outside the pupil groups by 0.04 ± 0.10 mm, 0.10 ± 0.11 mm, and 0.17 ± 0.12 mm, respectively. This means a 76% lesser AL growth or 0.13 mm/year in absolute reduction. OK corneal parameters can be modified by changing the OK lens designs, which affects myopia progression and AL elongation. Smaller BOZD induces a reduced PPRDs that slows AL elongation better than standard OK lenses. Further investigations should elucidate the effect of pupillary diameter, PPRD, and power change on myopia control.

Objectives: This study aimed at assessing the performance of a double tear reservoir toric reverse geometry contact lens design for the correction of myopic and astigmatic refractive errors through overnight orthokeratology (Ortho-K). Methods: Consecutive records of a total of 32 patients with refractive astigmatism greater than 1.25 D at any orientation, best corrected distance monocular visual acuity ≥1.00 (decimal) before Ortho-K treatment and stable ocular refraction for at least 1 month at the time of the last visit were retrospectively examined. Preorthokeratology and postorthokeratology information included noncycloplegic subjective refraction, best-corrected visual acuity, pupil diameter, corneal topography, and ocular aberrometry. The associations between the achieved myopic and cylinder reduction and the modifications in various corneal topographic parameters were investigated. Right eyes were chosen for data analysis. Results: A statistically significant difference (Z=−4.805; P<0.001) was encountered between initial refractive sphere and final residual refractive sphere, with a dioptric change of −2.05±1.46 D (median: −1.88; −5.25 to 0.50), accounting for a change of 106% of the initial myopia. Similarly, differences between pretreatment and posttreatment refractive cylinders were significant (Z=−4.945; P<0.001), with a dioptric change of −1.80±1.06 D (median: −1.50; −5.25 to −0.50), that is, a change of 85% of the initial astigmatism. Changes in topographic Best Fit Sphere and Best Fit Toric presented a strong positive correlation with the accomplished myopic and astigmatic refractive changes, respectively. Conclusions: The results of this investigation suggest that the correction of astigmatic errors with toric orthokeratology lens designs may have a promising future.

Purpose: The purpose of this work was to evaluate the potential of a novel custom‐designed rigid gas permeable (RGP) contact lens to modify the relative peripheral refractive error in a sample of myopic patients. Methods: Fifty‐two right eyes of 52 myopic patients (mean [±SD] age, 21 [±2] years) with spherical refractive errors ranging from −0.75 to −8.00 diopters (D) and refractive astigmatism of 1.00 D or less were fitted with a novel experimental RGP (ExpRGP) lens designed to create myopic defocus in the peripheral retina. A standard RGP (StdRGP) lens was used as a control in the same eye. The relative peripheral refractive error was measured without the lens and with each of two lenses (StdRGP and ExpRGP) using an open‐field autorefractometer from 30 degrees nasal to 30 degrees temporal, in 5‐degree steps. The effectiveness of the lens design was evaluated as the amount of relative peripheral refractive error difference induced by the ExpRGP compared with no lens and with StdRGP conditions at 30 degrees in the nasal and temporal (averaged) peripheral visual fields. Results: Experimental RGP lens induced a significant change in relative peripheral refractive error compared with the no‐lens condition (baseline), beyond the 10 degrees of eccentricity to the nasal and temporal side of the visual field (p < 0.05). The maximum effect was achieved at 30 degrees. Wearing the ExpRGP lens, 60% of the eyes had peripheral myopia exceeding −1.00 D, whereas none of the eyes presented with this feature at baseline. There was no significant correlation ( r = 0.04; p = 0.756) between the degree of myopia induced at 30 degrees of eccentricity of the visual field with the ExpRGP lens and the baseline refractive error. Conclusions: Custom‐designed RGP contact lenses can generate a significant degree of relative peripheral myopia in myopic patients regardless of their baseline spherical equivalent refractive error.

Purpose: The axial elongation in myopia is associated with some structural and functional retinal changes. The purpose of this study was to investigate the effect of a contact lens (CL) intended for myopia control on the choroidal thickness (ChT) and the retinal electrical response. Methods: Ten myopic eyes (10 subjects, 18–35 years of age) with spherical equivalents from −0.75 to −6.00 diopters (D) were enrolled. The ChT at different eccentricities (3 mm temporal, 1.5 mm temporal, sub-foveal ChT, 1.5 mm nasal, and 3 mm nasal), the photopic 3.0 b-wave of ffERG and the PERG were recorded and compared with two material-matched contact lenses following 30 min of wear: a single-vision CL (SV) and a radial power gradient CL with +1.50 D addition (PG). Results: Compared with the SV, the PG increased the ChT at all eccentricities, with statistically significant differences at 3.0 mm temporal (10.30 ± 11.51 µm, p = 0.020), in sub-foveal ChT (17.00 ± 20.01 µm, p = 0.025), and at 1.5 mm nasal (10.70 ± 14.50 µm, p = 0.044). The PG decreased significantly the SV amplitude of the ffERG photopic b-wave (11.80 (30.55) µV, p = 0.047), N35-P50 (0.90 (0.96) µV, p = 0.017), and P50-N95 (0.46 (2.50) µV, p = 0.047). The amplitude of the a-wave was negatively correlated with the ChT at 3.0T (r = −0.606, p = 0.038) and 1.5T (r = −0.748, p = 0.013), and the amplitude of the b-wave showed a negative correlation with the ChT at 1.5T (r = −0.693, p = 0.026). Conclusions: The PG increased the ChT in a similar magnitude observed in previous studies. These CLs attenuated the amplitude of the retinal response, possibly due to the combined effect of the induced peripheral defocus high-order aberrations impacting the central retinal image. The decrease in the response of bipolar and ganglion cells suggests a potential retrograde feedback signaling effect from the inner to outer retinal layers observed in previous studies.

The purpose of this study was to assess the effect of orthokeratology treatment with DRL lenses on the control of myopia progression compared with single vision glasses users (monofocal glasses). It was also possible to analyze the clinical efficacy of orthokeratology treatment with DRL lenses for myopia correction in children and adolescents in a 2 year retrospective, multicenter study, performed in eight different ophthalmology centers in France. A total of 360 data records of children and adolescents with myopia between −0.50 D and −7.00 D at baseline visit, who completed treatment and had a centered outcome, were selected for the study from a database of 1271. The final sample included subjects undergoing orthokeratology treatment with DRL lenses (n = 211 eyes) and spectacle wearers (n = 149 eyes). After one year of treatment, the data analysis shows that the DRL lens has a refractive myopia progression control rate of 78.5% compared with the spectacle wearers (DRL M change = −0.10 ± 0.25 D, p < 0.001 Wilcoxon test and Glasses M change = −0.44 ± 0.38 D, p < 0.001 Wilcoxon test). Similar results were found after 2 years of treatment (80% with 310 eyes). This study showed the clinical efficacy of orthokeratology DRL lenses compared to monofocal spectacle wearers in controlling myopia progression in children and adolescents in a 2 year retrospective study.