Orthokeratology effect on the corneoscleral profile: Beyond the bull's eye.

PURPOSE: To assess the impact of 3 months of orthokeratology (ortho-k) contact lenses (CLs) for myopia correction on the corneoscleral profile, as changes in scleral geometry could serve as indirect evidence of alteration in the corneal biomechanical properties. METHODS: Twenty subjects (40 eyes) were recruited to wear ortho-k lenses overnight; however, after discontinuation (two CL fractures, one under-correction and two non-serious adverse events), 16 subjects (31 eyes) finished a 3-month follow-up. Corneoscleral topographies were acquired using the Eye Surface Profiler (ESP) system before and after 3 months of lens wear. Steep (SimKs) and flat (SimKf) simulated keratometry and scleral sagittal height measurements for 13-, 14- and 15-mm chord lengths were automatically calculated by the ESP software. Additionally, sagittal height and slope were calculated in polar format from 21 radii (0-10 mm from the corneal apex) at 12 angles (0-330°). Linear mixed models were fitted to determine the differences between visits. RESULTS: SimKs and SimKf were increased significantly (p ≤ 0.02). The sagittal height in polar format increased significantly (p = 0.046) at a radius of 2.5 mm for 150°, 180°, 210° and 240° orientations and at a radius of 3.0 mm for 210°. Additionally, the slope in polar format significantly decreased (p ≤ 0.04) at radii ranges of 0.0-0.5, 0.5-1.0 and 1.0-1.5 mm for multiple angles and at a radii range of 5.0-5.5 mm for 90°. It also increased significantly (p ≤ 0.045) at a radii range of 1.5-2.0 mm for 30° and at radii ranges of 2.0-2.5, 2.5-3.0 and 3.0-3.5 mm for multiple angles. No significant changes were found for any parameter measured from the scleral area. CONCLUSIONS: Three months of overnight ortho-k lens wear changed the central and mid-peripheral corneal geometry as expected, maintaining the peripheral cornea and the surrounding sclera stability.

Axial length association with corneoscleral sagittal height and scleral asymmetry.

PURPOSE: To determine how corneoscleral geometry changes with axial length and to assess the usefulness of including the sagittal configuration of the anterior segment when predicting the axial length. METHODS: An observational study was performed including 96 healthy subjects (96 eyes). Axial length was calculated from optical biometry (IOL Master 500). Corneal curvature and scleral sagittal height parameters at 13, 14 and 15 mm were obtained automatically using corneoscleral topography (eye surface profiler; ESP). In addition, corneal and scleral sagittal heights at numerous locations (21 radii: 0-10 mm from the corneal apex at 12 angles: 0-330°) were calculated using the raw height data extracted from the ESP. The relationships between axial length and the study parameters were analysed using Pearson correlation analysis. The equations for the prediction of axial length were obtained by fitting multiple linear regression models. RESULTS: The temporal-nasal scleral asymmetry at 13-, 14- and 15-mm chord lengths was significantly correlated with axial length (r2 ≤ 0.26; p < 0.001). Significant inverse correlations were found between the temporal scleral sagittal height and axial length (r2 ≤ 0.28; p ≤ 0.02). The nasal scleral sagittal height was not associated with axial length. Three significant multiple linear regression models were fitted based on spherical equivalent, corneal radius and scleral asymmetry at 13 (r2 = 0.79; p < 0.001), 14 (r2 = 0.80; p < 0.001) and 15 (r2 = 0.80; p < 0.001) mm chord lengths. CONCLUSIONS: Larger ocular globes show reduced temporal-nasal scleral asymmetry, mainly due to the lower sagittal height of the temporal sclera. Thus, the geometry of the temporal scleral may be a factor of interest during myopia progression.

Efficacy of Presbyopia-Correcting Contact Lenses: A Systematic Review.

PURPOSE: To analyze critically the clinical trials on presbyopia correction with contact lenses (CLs) to investigate the quality of the research performed. METHODS: A search was performed in PubMed database on clinical trials evaluating the efficacy of the presbyopia correction with different CLs, including multifocal or simultaneous vision contact lenses (MCLs). After a comprehensive analysis of the relevant publications found, quality assessment of such publications was performed by means of Critical Appraisal Skills Programme checklist tool according to the five types of evaluations: MCL versus spectacles, MCL versus pinhole CLs, MCL versus monovision, comparison between MCL designs, and MCL versus extended depth of focus CLs. RESULTS: A total of 16 clinical trials were selected for evaluation. All evaluated studies addressed a clearly focused research question and were randomized, with a crossover design in most of the cases. Blinding was not possible in all cases due to the physical appearance of some of the CLs evaluated (pinhole or hybrid designs). Most of studies analyzed reported outcomes with complete data, providing the statistical tests used and the P -values, but some of the authors did not provide the statistical power associated to the sample size evaluated. The small sample size in some trials as well as the scarce information about the effect of addition on visual performance was the main limitations found in the peer-reviewed literature revised. CONCLUSIONS: There is a high-quality scientific evidence supporting the use of presbyopia-correcting CLs, with several randomized controlled clinical trials conducted to this date.

Inter-eye and postoperative prediction of vault after implantation of EVO + Visian phakic implantable collamer lens.

PURPOSE: To assess whether the postoperative outcomes of the implantation of an EVO + implantable collamer lens (ICL) in one eye can be used as a predictor of the vault of the fellow eye, and to evaluate the vault changes of the implantation in both eyes during the postoperative period. METHODS: A prospective study including 40 eyes of 20 patients with a bilateral EVO + ICL implantation was performed. Subjects were evaluated before the surgery and 1 day, 1 week and 1, 3 and 6 months postoperatively. Central vault was assessed using spectral-domain optical coherence tomography. The inter-eye and follow-up analyses were performed using lineal models and the Bland-Altman method. RESULTS: The vault of the first implanted eye at the 1-day visit highly predicts the vault of the second eye (R2 = .87; P < .001); the mean inter-eye difference was - 0.95 µm, and the superior and inferior limits of agreement were -50.27 µm and 148.37 µm, respectively. This relationship was maintained during the medium-term follow-up, not finding differences in the slopes among visits (P ≥ .09). A progressive decrease of vault was found during the follow-up (P < .001). Larger vault change 6 months after the surgery was associated with higher vault 1 day after the ICL implantation (R2 = .19;P = .005). CONCLUSION: One-day postoperative vault in the first eye can help to predict the optimal ICL sizing in the second eye. Vault tends to decrease during the first 6 months after EVO + ICL implantation. Eyes with higher initial vaults will also show larger reductions during the medium-term follow-up.

Assessment of the iridocorneal angle pigmentation and structures after the implantation of EVO+ Visian Implantable Collamer Lens.

PURPOSE: To evaluate the effect of EVO+ Visian Implantable Collamer Lens (ICL) implantation on the iridocorneal angle pigmentation and structures. METHODS: Myopic refractive surgery candidates who underwent posterior chamber EVO+ ICL implantation were evaluated preoperatively and 3 and 6 months postoperatively. High-resolution images of the iridocorneal angle (nasal, superior, temporal and inferior quadrants) were acquired during gonioscopy. A masked observer, blinded to study visits and patients' information, evaluated the angle width, apparent iris root insertion, iris configuration, and trabecular meshwork pigmentation according to the Spaeth scale in two different occasions. The intra-rater reliability was estimated using the weighted Gwet's Agreement Coefficient (AC2). Differences between visits were analyzed using the Cochran Q test or the Friedman test. RESULTS: Twenty-one patients (13 females and 8 males) aging 31.3 ± 6.3 years old were recruited. The intra-rater reliability of gonioscopy assessment was excellent for every parameter assessed (AC2 ≥ 0.97). No significant differences were found among the study visits for any quadrant in the angle width (p ≥ 0.74), apparent iris root insertion (p ≥ 0.22), iris configuration (p ≥ 0.21) and trabecular meshwork pigmentation (p ≥ 0.24). Mean pigmentation of trabecular meshwork for the four quadrants did not vary either among visits (p = 0.25). CONCLUSIONS: The EVO+ ICL implantation after uneventful procedures appears not to clinically affect the iridocorneal angle pigmentation and/or structures during a short-medium follow-up using gonioscopy assessment. The intra-rater reliability of glaucoma specialists assessing iridocorneal angle structures using gonioscopy images is very high.

Inflammation-related molecules in tears of patients with chronic ocular pain and dry eye disease.

The purpose of this study was to analyze inflammation- and pain-related molecules in tears of patients suffering from chronic ocular pain associated with dry eye (DE) and/or a previous corneal refractive surgery (RS). Based on history, symptomatology, and clinical signs, the subjects (n = 180, 51.0 ± 14.7 years, 118 females, 62 males) in this cross-sectional study were assigned to one of five groups: DE and chronic ocular pain after RS (P/DE-RS, n = 52); asymptomatic subjects, i.e., without DE and chronic ocular pain, after RS (A-RS, n = 30); DE and chronic ocular pain without previous RS (P/DE-nonRS, n = 31); DE, no pain, and no previous RS (DE-nonRS, n = 35); and asymptomatic subjects with no previous RS (controls, n = 32). The tear concentrations of 20 cytokines and substance P (SP) were analyzed by immunobead-based assay and enzyme-linked immunosorbent assay, respectively. We found that tear levels of interleukin (IL)-10 and SP were increased in the RS groups. There were significant differences in IL-8/CXCL8 among the five groups. Nerve growth factor (NGF) tear levels were significantly higher in P/DE-RS than in DE-nonRS and controls. IL-9 had the highest percentage of detection in the P/DE-RS and P/DE-nonRS groups, while macrophage inflammatory protein (MIP)-1α, IL-2, and interferon (IFN)-γ were higher in the P/DE-RS, A-RS, and P/DE-nonRS groups. IL-17A was detected only in the A-RS group. Moderate correlations were observed in the A-RS, P/DE-nonRS, DE-nonRS and controls groups. A positive correlation was obtained between growth related oncogene concentration and tear break-up time (rho = 0.550; p = 0.012), while negative correlation was found between monocyte chemoattractant protein-3/CCL7 and conjunctival staining (rho = -0.560; p = 0.001), both in the A-RS group. IL-10 correlated positively with ocular pain intensity (rho = 0.513; p = 0.003) in the P/DE-nonRS group. Regulated on Activation Normal T Cell Expressed and Secreted/CCL5 correlated negatively with conjunctival staining (rho = -0.545; p = 0.001) in the DE-nonRS group. SP correlated negatively with corneal staining (rho = -0.559; p = 0.001) in the controls. In conclusion, chronic ocular pain was associated with higher IL-9 tear levels. IL-10, SP, MIP-1α/CCL3, IL-2, and IFN-γ were associated with previous RS. Higher levels of IL-8/CXCL8, MIP-1α/CCL3, IL-2, and IFN-γ were associated with DE-related inflammation, while NGF levels were related to chronic ocular pain and DE in RS patients. These findings suggest that improved knowledge of tear cytokines and neuromodulators will lead to a more nuanced understanding of how these molecules can serve as biomarkers of chronic ocular pain, leading to better therapeutic and disease management decisions.

Reliability and Agreement of Keratometry Measurements Obtained With Eye Surface Profilometry and Partial Coherence Interferometry.

PURPOSE: The aim of this study was to assess the repeatability of keratometry parameters obtained using the Eye Surface Profiler (ESP) system and their agreement with the IOL Master 500 device. METHODS: Seventy-one eyes of 71 healthy participants were evaluated. Three repeated measurements were performed using the ESP system. Simulated keratometry in the flat (SimKf) and steep (SimKs) meridians, astigmatism, and axis were obtained. The same parameters were measured using the IOL Master 500 device. The J0 and J45 vector components of the astigmatism were calculated. The intrasession repeatability was analyzed using within-subject SD (Sw) and intraclass correlation coefficient (ICC). Agreement was assessed using paired statistical tests and the Bland-Altman method. RESULTS: The Sw was 0.07 mm, 0.04 mm, 0.51 D, 0.33 D, and 0.22 D, and the ICC was 0.96, 0.98, 0.74, 0.61, and 0.55 for SimKf, SimKs, astigmatism, J0, and J45, respectively. The mean difference and limits of agreement when comparing the ESP system with the IOL Master 500 device were 0.37 mm (0.08/0.66) for SimKf ( P < 0.001), 0.18 mm (0.00/0.35) for SimKs ( P < 0.001), -0.93 D (-2.42/0.56) for astigmatism ( P < 0.001), 0.51 D (-0.22/1.24) for J0 ( P < 0.001), and 0.06 D (-0.48/0.60) for J45 ( P = 0.09). CONCLUSIONS: The ESP system provides consistent values for simulated keratometry, showing moderate consistency for astigmatism parameters. Contact lens practitioners should be aware that the ESP system and IOL Master 500 device provide different simulated keratometry from a clinically viewpoint.

Professional perspective and practice patterns of vision therapy in Spain.

CLINICAL RELEVANCE: An analysis of the professional perspective of vision therapy (VT) by eye care professionals allows understanding the current controversies about this therapeutic option of which aspects can be improved for its correct application in clinical practice. BACKGROUND: The aim of the current study was to analyse the perception of VT and the clinical protocols in this context followed among optometrists and ophthalmologists in Spain. METHODS: A cross-sectional survey among Spanish optometrists and ophthalmologists. Google Forms tool was used to collect data via an online questionnaire divided into 4 sections (40 questions): consent to participate, demographic characteristics, opinion of the professional perspective of VT, and protocols. Only one submission from each email address was permitted by the survey tool. RESULTS: A total of 889 Spanish professionals answered (age, 25-62 years): 848 optometrists (95.4%) and 41 ophthalmologists (4.6%). VT was considered as a scientifically-based procedure by 95.1% of participants, but its recognition and prestige was considered as low. The main cause reported for this was bad reputation or perception of placebo therapy (27.3%). The main indication of VT according to the surveyed professionals was convergence and/or accommodation problems (72.4%). Significant differences were found in the perception of VT among optometrists and ophthalmologists (p ≤ 0.027). A total of 45.3% of professionals reported performing VT in their current clinical practice. A combination of training sessions in office and home was regularly prescribed by 94.5% of them, but with significant variability in the duration of such sessions. CONCLUSIONS: VT is perceived by Spanish optometrists and ophthalmologists as a therapeutic option with scientific basis, but with limited recognition and prestige, although with more negative perception among ophthalmologists. A great variability was found in the clinical protocols followed between specialists. Future efforts should be focused on creating internationally recognised evidence-based protocols for this therapeutic option.

Safety, Efficacy, and Visual Performance of an Orthokeratology Lens with Increased Compression Factor.

The aim was to evaluate the safety, efficacy, and visual performance of an orthokeratology lens with an increased compression factor (ICF) of 1.25 D in a 3-month follow-up. Thirty-six myopic patients (5 males and 31 females; 24.2 ± 5.8 years) were fitted with Alexa AR (Tiedra Farmacéutica S.L., Madrid, Spain) contact lenses (CLs) and twenty participants finished the follow-up. Visual acuity (VA), subjective refraction, primary spherical and primary coma aberrations, keratometry, central pachymetry, and ocular surface evaluation were performed at baseline and after 1 night, 1 week, 1 month, and 3 months of CL wear. The differences among visits were analyzed using a repeated-measures analysis of variance or the Friedman test. The spherical equivalent decreased (p ≤ 0.005), and the uncorrected VA improved (p < 0.001) until the first week. Corneal and ocular aberrations showed a significant increase (p ≤ 0.02). A significant decrease (p < 0.001) was found for keratometry values. No significant changes were observed in either central pachymetry or ocular surface parameters among study visits. In conclusion, an orthokeratology CL with an ICF of 1.25 D provides good safety, efficacy, and visual performance in a 3-month follow-up. Seven days of orthokeratology wear are enough to achieve the full myopic compensation, resulting in satisfactory VA.

Diagnostic Performance of Visionix VX120+ Platform for Dry Eye Screening.

OBJECTIVE: To evaluate the accuracy of diagnosing dry eye disease (DED) by using the Visionix VX120+, to establish reference values for tear meniscus height (TMH) and non-invasive break-up time (NIBUT), and to compare the NIBUT measurements with the fluorescein tear break-up time (FBUT), Methods: fifty-eight subjects (34 dry eye and 24 control) were enrolled. The TMH, first NIBUT, and NIBUT50% were evaluated with the Visionix VX120+, and the FBUT was measured with a slit-lamp. The Receiver Operating Characteristic (ROC) curve was used to evaluate the diagnostic performance, and the Bland-Altman method was performed to analyze the agreement. RESULTS: The areas under the curve were 0.62, 0.60, and 0.70 for the TMH, first NIBUT, and NIBUT50%, respectively. The optimal cut-off values (sensitivity, specificity) were 0.29 (0.62, 0.67), 5.05 (0.85, 0.46), and 7.35 (0.65, 0.79) for the TMH, first NIBUT, and NIBUT50%, respectively. The mean differences (lower, upper limits of agreement) were -1.10 (-8.78, 6.58) and 1.55 (-5.68, 8.78) for the first NIBUT vs. FBUT and the NIBUT50% vs. FBUT, respectively. CONCLUSIONS: In conclusion, the NIBUT50% can be a useful tool for dry eye screening, with acceptable values of sensitivity and specificity. First, the NIBUT and NIBUT50% should not be used interchangeably with the FBUT.

Professional perspective of vision therapy worldwide among optometrists and ophthalmologists.

CLINICAL RELEVANCE: Perception of optometrists and ophthalmologists of vision therapy (VT) as well as their methods for performing the sessions is of great importance for understanding the problems that professionals face and what should be improved in their clinical practice. BACKGROUND: The objective of this study was to determine the perception of VT and protocols used by eye care professionals globally. METHODS: A cross-sectional study was performed among eye care professionals internationally. The participants completed via online (Google Forms) a questionnaire of 40 questions on their perception and clinical practice of VT. The survey only permitted one answer per email address and was only collected if professionals gave their consent to participate. RESULTS: A total of 205 professionals from 43 countries answered the questionnaire (171 optometrists and 34 ophthalmologists). Accommodation and convergence problems were the main indication reported for VT (47.8%), followed by amblyopia (26.3%). The principal negative factor associated to VT was the limited number of professionals dedicated to this field (55.6%). The most common program of VT was the combination of VT sessions at home and at office (85.5%), with a great variability in terms of duration. Few professionals made use of the new technologies when programming VT, such as eye trackers (2.7%) or virtual reality (6.4%). European professionals surveyed had a more negative perception of VT (p < 0.031). CONCLUSIONS: Eye care professionals globally perceive VT as a scientifically based procedure. Overall, they believe that it has low recognition and prestige, especially ophthalmologists. A great variability in the programming of VT sessions was found, which highlights the need for standardised protocols that professionals could follow in their clinical practice.

Senile Cataract Formation Does Not Affect Crystalline Lens Thickness.

INTRODUCTION: Characterizing lens thickness (LT) in patients with cataracts is important for better understanding the lens aging process and for designing new intraocular lens power formulas. This study aimed to analyze the influence of common senile cataract formation on the LT, anterior (ACS) and posterior (PCS) cortex space, and nuclear thickness (NT), controlling for sex, age, and axial length. METHODS: A cross-sectional study was performed. A consecutive sample of 603 volunteers (403 women, 200 men) aged 59.1 ± 18.8 years was recruited. The standardized Lens Opacification Classification System (LOCS)-III was used to classify eyes (randomly selected) into cataractous and non-cataractous groups. Also, they were classified according to the cataract location (presence or absence of cortical, nuclear, or posterior subcapsular cataract). Optical biometry was performed to measure LT, ACS, NT, and PCS. Propensity score was used to match participants one-to-one for sex, age, and axial length. Groups were compared using the Student's t test or Yuen's test. RESULTS: The four classifications divided unmatched eyes into: 361 cataractous lenses and 242 non-cataractous, 226 cortical and 377 non-cortical cataractous, 313 nuclear and 290 non-nuclear cataractous and 242 subcapsular and 361 non-subcapsular cataractous. Before matching, cataractous eyes showed significantly higher LT (4.52 ± 0.39 vs. 3.94 ± 0.46 mm, p < 0.001), ACS (0.75 ± 0.20 vs. 0.58 ± 0.23 mm, p < 0.001), NT (3.34 ± 0.23 vs. 3.18 ± 0.25 mm, p < 0.001) and PCS (0.42 ± 0.19 vs. 0.37 ± 0.19 mm, p = 0.003). Matched lens, cortical, nuclear, and subcapsular cataract samples comprised 146, 258, 182, and 226 eyes, respectively. After matching, no significant differences were observed in LT (4.34 ± 0.37 vs. 4.33 ± 0.36 mm, p = 0.94), ACS (0.72 ± 0.20 vs. 0.76 ± 0.19 mm, p = 0.08), NT (3.31 ± 0.22 vs. 3.30 ± 0.23 mm, p = 0.24) and PCS (0.42 ± 0.19 vs. 0.43 ± 0.16 mm, p = 0.79). CONCLUSIONS: The presence of senile cortical, nuclear, and posterior subcapsular cataract have no effect on LT, ACS, NT, and PCS. Confounding factors should be controlled for when measuring LT and its main components.

EVO/EVO+ Visian Implantable Collamer Lenses for the correction of myopia and myopia with astigmatism.

INTRODUCTION: Intraocular lens implantation in phakic eyes for the correction of refractive error is currently a widespread procedure. The EVO and EVO+ Visian Implantable Collamer Lenses (ICL) are two of the most prevalent lenses implanted. They incorporate a central orifice to avoid the need for iridotomy. The main difference between both ICL is the higher optical diameter zone provided by the EVO+, allowing a better quality of vision at night. This review aims to provide an overview of the current ICL models available for correcting myopia and myopic astigmatism. AREAS COVERED: During the last decade, more than 100 scientific papers analyzing the performance of EVO and EVO+ lenses have been published. This review describes the objective visual performance achieved with the implantation of central hole ICL lenses and the subjective perception of the patients implanted with these lenses. In addition, the safety and the potential complications associated with undergoing an EVO and EVO+ ICL implantation have been addressed. EXPERT OPINION: Refractive surgeons and candidates to undergo ICL implantation should be aware of the excellent safety and visual outcomes provided by the implantation of central hole ICL lenses. However, future research could address minor issues currently not resolved.

Reliability and agreement of apparent chord mu measurements between static and dynamic evaluations.

PURPOSE: To assess the repeatability and agreement of Cartesian coordinates and the length of apparent chord mu and pupil diameter measurements during static (Galilei G4) and dynamic (Topolyzer Vario) evaluations. SETTING: IOBA-Eye Institute, Valladolid, Spain. DESIGN: Case series. METHODS: 3 consecutive measurements per scenario (Galilei G4 and Topolyzer Vario under low mesopic and photopic conditions) were performed by the same clinician. The intrasession repeatability was assessed using the within-subject SD (Sw), the precision, the coefficient of variation, and the intraclass correlation coefficient (ICC). The agreement was analyzed using repeated-measures analysis of variance and the Bland-Altman method. RESULTS: Thirty-seven healthy participants were recruited. The Sw values for chord mu parameters and pupil diameter ranged from 0.01 to 0.03 and 0.08 to 0.21, respectively. The ICC was ≥0.89 for all parameters. Galilei G4 and Topolyzer Vario under low mesopic and photopic conditions provided significantly different measures of apparent chord mu length (0.23 ± 0.11 mm, 0.30 ± 0.10 mm, and 0.25 ± 0.11 mm, respectively, P ≤ .02), X-coordinate (-0.18 ± 0.12 mm, -0.27 ± 0.11 mm, and -0.21 ± 0.12 mm, respectively, P < .001), and pupil diameter (3.38 ± 0.50 mm, 6.29 ± 0.60 mm, and 3.04 ± 0.41 mm, respectively, P < .001). Y-coordinate values obtained by Galilei G4 and Topolyzer Vario under low mesopic conditions were significantly different (0.06 ± 0.13 mm vs 0.03 ± 0.11 mm, respectively, P = .02), in contrast to Galilei G4 and Topolyzer Vario under photopic conditions (0.05 ± 0.13 mm, P = .82) and both illumination conditions of Topolyzer Vario (P ≥ .23). CONCLUSIONS: Galilei G4 and Topolyzer Vario provide consistent measurements of apparent chord mu Cartesian coordinates and length, as well as pupil diameter; however, the measurements are not interchangeable. Ophthalmic surgeons should consider these findings when planning customized intraocular lens implantation and refractive surgery procedures.

Amblyopia Treatment through Immersive Virtual Reality: A Preliminary Experience in Anisometropic Children.

The use of digital devices provides a wide range of possibilities for measuring and improving visual function, including concepts such as perceptual learning and dichoptic therapy. Different technologies can be used to apply these concepts, including, in recent years, the introduction of virtual reality (VR) systems. A preliminary experience in treating anisometropic amblyopia through an immersive VR device and using prototype software is described. A total of 4 children were treated by performing 18 office-based sessions. Results showed that distance VA in amblyopic eyes remained constant in two subjects, whereas the younger subjects improved after the training. Near VA improved in three subjects. All subjects showed an increase in the stereopsis of at least one step, with three subjects showing a final stereopsis of a 60 s arc. A total of three subjects showed an increase of approximately 0.5 CS units for the spatial frequency of 3 cpd after the training. Results from this pilot study suggest that visual training based on perceptual learning through an immersive VR environment could be a viable treatment for improving CS, VA, and stereopsis in some children with anisometropic amblyopia. Future studies should support these preliminary results.

Influence of decentration and tilt of Tecnis ZCB00 on visual acuity and higher order aberrations.

BACKGROUND/OBJECTIVES: To determine the influence of decentration and tilt of a pseudophakic aspheric intraocular lens (IOL) on visual acuity (VA) and higher-order aberrations (HOAs), and to analyze the agreement between pupil center/axis and iridocorneal angles center/axis when assessing IOL decentration and tilt. SUBJECTS/METHODS: A prospective interventional case series study including thirty-three patients undergoing Tecnis ZCB00 (Abbott Medical Optics) implantation. IOL decentration and tilt with respect to two reference systems (pupil and iridocorneal angles centers/axes), in cartesian (X,Y) and polar (radius/tilt, polar angle/azimuth) coordinates, were assessed with optical coherence tomography. VA and internal and ocular HOAs were evaluated. Multiple linear regression models and intraclass correlation coefficient (ICC) were computed. RESULTS: IOL decentration only showed a significant effect on internal HOAs for [Formula: see text] (R2 = 0.20, P = 0.04). IOL decentration with respect to the pupil center showed a significant effect on ocular [Formula: see text] (R2 = 0.18, P = 0.05), [Formula: see text] (R2 = 0.36, P = 0.001) and [Formula: see text] (R2 = 0.24, P = 0.02); and with respect to the center of iridocorneal angles, on ocular [Formula: see text] (R2 = 0.21, P = 0.03), [Formula: see text] (R2 = 0.32, P = 0.003), primary coma (R2 = 0.41, P < 0.001), and coma-like (R2 = 0.40, P = 0.001). Poor agreement between both reference systems was found for IOL decentration measurements (ICC ≤ 0.41), except for the polar angle coordinate (ICC = 0.83). Tilt measurements showed good agreement (ICC ≥ 0.75). CONCLUSIONS: Tecnis ZCB00 decentration and tilt values after uneventful implantation appear not to have influence on VA, and their effect on HOAs are not high enough to clinically affect quality of vision. Pupil and iridocorneal angles used as reference systems may be interchangeable for IOL tilt measurements, but not for decentration.

Mesopic Disability Glare in Stage-Two Dysfunctional Lens Syndrome.

INTRODUCTION: There is a lack of evidence about the exact deterioration of visual function associated with the age-related natural changes in the lens, particularly in intermediate (stage-2) dysfunctional lens syndrome (DLS). Standard photopic visual acuity and contrast sensitivity tests may not show the visual worsening in daily life activities, such as oncoming vehicle headlights at night. The purpose of this study was to analyze visual function under different conditions and glare sources in stage-2 DLS. METHODS: Forty patients over 49 years of age with initial bilateral lens opacification (Lens Opacities Classification System III [LOCS-III] scores up to 3), best-corrected visual acuity of 20/25 or better, and no ocular disease were evaluated. Binocular photopic and mesopic contrast sensitivity (CS) with/without halogen and xenon increasing glare sources were analyzed. Mesopic disability glare (MDG) was calculated as the difference between mesopic CS with/without the glare source. RESULTS: The median logarithmic CS (logCS) values were lower under mesopic conditions (1.05) than under photopic illumination (1.65; P < 0.001). Halogen and xenon glare further decreased mesopic CS (both, median logCS 0.75, P < 0.001). The mean MDG was 0.31 ± 0.10 log units for halogen glare and 0.33 ± 0.09 log units for xenon glare. The mesopic CS and MDG were not associated with any photopic test. The mesopic CS with glare but not photopic CS or mesopic CS was correlated with the LOCS-III scores. The best association was provided by MDG, which showed a pooled correlation with LOCS-III nuclear opalescence (r = 0.411, P < 0.001) and cortical scores (r = 0.226, P = 0.04). CONCLUSION: The mesopic CS under a glare source is an independent early indicator of visual impairment in stage-2 DLS patients, and appears to be substantial. Furthermore, the MDG is more sensitive than photopic and mesopic CS for evaluating patients with initial phacosclerosis. Surgeons should consider this in the decision-making process of the correct timing for lens surgery.

Clinical Validation of a New Optical Biometer for Myopia Control in a Healthy Pediatric Population.

To assess the clinical validation of the Myah device in a pediatric population by evaluating the repeatability of biometric evaluations and analyzing its agreement with the Myopia Master system. A total of 51 children (51 eyes) were enrolled. Repeated measurements of flat (K1) and steep (K2) corneal radius, white-to-white (WTW) distance and axial length (AL) were performed with the Myah device. The same parameters were obtained from a subgroup (30 eyes) with the Myopia Master for the agreement analysis. The repeatability was assessed using the intrasubject standard deviation (Sw) and the intraclass correlation coefficient (ICC). The agreement was analyzed using the Bland−Altman method and the paired Student t-test. The Sw was 0.018 D, 0.021 D, 0.071 mm and 0.017 mm for K1, K2, WTW and AL, respectively (ICC ≥ 0.971). The mean difference and limits of agreement when comparing instruments were −0.013 (−0.102/0.077) for K1 (p = 0.16), −0.058 (−0.127/0.012) for K2 (p < 0.001), 0.151 (−0.370/0.673) for WTW (p < 0.001) and 0.030 (−0.091/0.151) for AL (p = 0.009). In conclusion, the Myah device provides consistent measurements of corneal radius, WTW distance and AL in a healthy pediatric population, validating their usefulness in clinical practice. These measurements could be used interchangeably with those provided by the Myopia Master device, although with some caution.

Characterization of Dysfunctional Lens Index and Opacity Grade in a Healthy Population.

This study enrolled 61 volunteers (102 eyes) classified into subjects < 50 years (group 1) and subjects ≥ 50 years (group 2). Dysfunctional Lens Index (DLI); opacity grade; pupil diameter; and corneal, internal, and ocular higher order aberrations (HOAs) were measured with the i-Trace system (Tracey Technologies). Mean DLI was 8.89 ± 2.00 and 6.71 ± 2.97 in groups 1 and 2, respectively, being significantly higher in group 1 in all and right eyes (both p < 0.001). DLI correlated significantly with age (Rho = −0.41, p < 0.001) and pupil diameter (Rho = 0.20, p = 0.043) for all eyes, and numerous internal and ocular root-mean square HOAs for right, left, and all eyes (Rho ≤ −0.25, p ≤ 0.001). Mean opacity grade was 1.21 ± 0.63 and 1.48 ± 1.15 in groups 1 and 2, respectively, with no significant differences between groups (p ≥ 0.29). Opacity grade significantly correlated with pupil diameter for right and all eyes (Rho ≤ 0.33, p ≤ 0.013), and with some ocular root-mean square HOAs for right and all eyes (Rho ≥ 0.23, p ≤ 0.020). DLI correlates with age and might be used complementary to other diagnostic measurements for assessing the dysfunctional lens syndrome. Both DLI and opacity grade maintain a relationship with pupil diameter and internal and ocular HOAs, supporting that the algorithms used by the device may be based, in part, on these parameters.

EVO+ Implantable Collamer Lens KS-aquaPORT Location, Stability, and Impact on Quality of Vision and Life.

PURPOSE: To determine the longitudinal variation in the KS-aquaPORT central hole location of the phakic EVO+I Implantable Collamer Lens (ICL) (STAAR Surgical) and analyze its influence on visual performance, quality of vision (QoV), and quality of life (QoL). METHODS: A prospective study was performed including 36 patients who had EVO+ ICL implantation. The KS-aquaPORT central hole location (Cartesian and polar coordinates) was determined with respect to the pupil center and visual axis. The effect of time (6-month follow-up) on central hole location was analyzed using linear mixed models. The effect of the KS-aquaPORT location on visual performance, QoV, and QoL parameters was assessed with multivariate regression models. RESULTS: With respect to the visual axis, no significant changes in KS-aquaPORT location were found during follow-up. With respect to the pupil center, the X-coordinate and radius of KS-aquaPORT location showed modest, but significant (P ≤ .05) differences between 1-week and 3-month postoperative visits, and between 1-week and 6-month visits. X-coordinate variation was significant (P = .022) between 1-and 6-month visits. With respect to the visual axis, greater KS-aquaPORT decentration was associated with worse visual acuity (X-coordinate: P = .004; radius: P = .006), and inferior decentration with longer xenon-type glare photostress recovery time (P = .021). With respect to the pupil center, a lower radius was associated with better QoV scores (P ≤ .01) and temporal decentration produced higher ring-shaped dysphotopsia (P = .007). CONCLUSIONS: EVO+ ICL KS-aquaPORT location appears to be clinically stable up to 6 months postoperatively. A central location of the EVO+ ICL KS-aquaPORT hole is preferred because it allows reduced perception of dysphotopic phenomena that can result in better QoV. [J Refract Surg. 2022;38(3):177-183.].