Dawn Meyer

Purpose: To quantify the impact of uncorrected astigmatism in myopic eyes fitted with dual focus (DF) myopia control contact lenses. Methods: The right eyes of 10 young adult myopes were corrected with standard single vision (SV, Proclear 1 day, CooperVision, Inc.) and DF (MiSight 1 day, CooperVision, Inc.) contact lenses. SV and DF contact lens powers were determined from SV over-refractions and any ocular astigmatism was corrected using cylindrical trial lenses. Visual acuity and subjective vision were measured through added cylindrical trial lenses (0.00DC, 0.75DC, 1.25DC, 1.75DC and 2.25DC) with spherical equivalent adjustments. With the 2.25D astigmatic lenses, spherical trial lenses were also used to focus the front edge, centre and back edge of the interval of Sturm. Data were analysed using linear mixed-effects regression models. Results: High illumination visual acuity was similar for both lens types (zero astigmatism model-estimated intercept: −0.25 logMAR for SV; −0.24 logMAR for DF), and visual acuity decreased linearly with increasing astigmatism, similarly with both SV (0.27 logMAR/D) and DF (0.23 logMAR/D) lenses. Under low room illumination and in the absence of astigmatism, SV acuity was slightly superior to DF (mean logMAR −0.03 and +0.06 for SV and DF, respectively) and the rate of visual acuity decline with increasing astigmatism was less for DF (0.21 logMAR/D) than for SV lenses (0.26 logMAR/D; p = 0.04). Subjective quality of vision ratings were higher for SV lenses compared to DF lenses (model-estimated intercept: 93 vs. 86). Quality of vision ratings decreased linearly with increasing astigmatism at nearly identical rates for both lens types (~19 rating units/D). LogMAR acuity and subjective ratings were similar when the edges or the centre of the interval of Sturm were focused. Conclusion: Uncorrected astigmatism had an almost identical impact on visual acuity and vision quality in eyes fitted with DF myopia control and SV contact lenses.

Stress-related endocrine responses are critical for understanding human performance and mental health. Conventional assessments rely heavily on subjective self-report questionnaires or invasive sampling such as venipuncture. Tears offer a noninvasive source of neurochemical biomarkers, including serotonin, a key regulator of stress and mood. However, real-time and continuous monitoring of tear serotonin has not yet been fully realized. Here, we present a reversible lab-on-a–contact lens platform that integrates a printable, stretchable ferrocene-based electrochemical sensor for in situ detection of serotonin in tear fluid. The device is fabricated on a soft hydrogel lens and uses an electrochemically refreshable redox surface to restore baseline between measurements. Calibration in artificial tears established a limit of detection of 72 picomolar and a dynamic range of 0.1 to 500 nanomolar. Function was maintained for more than 28 days in a tear-like environment and under repeated mechanical deformations (flipping, folding, stretching, and twisting), with stability confirmed by periodic redox cycling. Ocular safety and biocompatibility were demonstrated in a porcine eye model. In a chronic stress mouse model, tear serotonin concentrations inversely correlated with cortisol in both serum and tears, and a first-in-human pilot study further supported the relationship between tear serotonin and stress with off-line analysis by the lab-on-a–contact lens platform. This platform could enable applications in decentralized, noninvasive endocrine monitoring and holds promise as a clinically translatable tool for real-time mental health biomarker assessment.

Dry eye disease (DED) is a prevalent ocular condition characterized by tear film instability, hyperosmolarity, inflammation, and neurosensory abnormalities. Its episodic and fluctuating nature complicates diagnosis and management, as conventional clinical assessments often fail to capture transient tear film changes. Although emerging tear‐sensing technologies show promise, many rely on trained personnel, only sporadic measurements, external readers, or integrated electronics, limiting their practicality for in‐eye applications. Here, we present an electronics‐free scleral lens platform for wearable monitoring of DED‐related tear biomarker changes using passive colorimetric sensors integrated within the lens tear reservoir. This configuration enables visual and smartphone‐assisted readout of chloride ions, pH, and ocular surface temperature within physiologically relevant ranges while avoiding direct contact with the corneal surface. The vaulted scleral lens geometry forms a stable, self‐replenishing tear reservoir that concentrates biomarkers while shielding sensors from corneal contact and eyelid pressure. Sensor color changes are directly observable and quantifiable via a smartphone without specialized readers or user‐specific calibration. Validated using artificial tear fluids, human tear samples, and in vivo models, this platform enables wearable monitoring of DED‐related biomarkers within physiologically relevant ranges, offering a simple and clinically viable approach for tracking ocular surface conditions and associated treatment efficacy.

Purpose: To explore the agreement between computationally modelled point‐spread functions (PSFs) and multifocal soft contact lens wearers' descriptions of image quality. Methods: In Phase 1, participants were fitted with a single vision soft contact lens (SCL) in the left eye, and four different multifocal (MF) SCLs in the right eye in randomised order. Aberrometry measures of the MFSCL‐wearing right eye were collected while participants viewed a point source monocularly using their left eye and drew their perception of the source. The predicted right eyes' PSFs were computed from the aberrometry data using a geometrical optics PSF calculation. In Phase 2, participants completed a Likert item questionnaire designed to identify salient features in the PSFs. Consensus among the participants about these features was assessed quantitatively using Yule's Q . Participants also rated the similarity between pairs of PSFs. Non‐metric multidimensional scaling (MDS) and Procrustes transformation analyses were used to derive and compare image similarity spaces for the drawn and computed PSFs, respectively. Lastly, two observers completed an image matching task, in which they selected the best‐matching drawn PSF for each computed PSF. Results: Significant similarities between computed and hand‐drawn PSFs were demonstrated both qualitatively and quantitatively. Inter‐rater agreement for image features was statistically significant (Yule's Q = 0.63; p < 0.05). Stress values for three‐dimensional MDS configurations were p < 0.001). Conclusions: Results indicate good agreement between the PSF image quality drawn by participants and that predicted from aberrometry measures. This study has demonstrated potential for leveraging the correspondence between subjectively perceived and computationally derived representations of image quality in both clinical and contact lens research and development processes.

Purpose: To evaluate the myopic and hyperopic defocus delivered to the retina by a dual focus (DF) myopia control contact lens when myopia exceeds 6.00 D. Methods: Individuals with high myopia were fitted bilaterally with high‐powered DF lenses containing power profiles matching a Coopervision MiSight 1 day contact lens (omafilcon A) and a Coopervision Proclear 1 day single vision (SV) lens. Wavefront measurements along the primary line of sight and across the central ±20° of the horizontal retina were acquired using a pyramidal aberrometer, while subjects accommodated to high‐contrast letter stimuli (6/12 equivalent) at six target vergences (−0.25 and −1.00 to −5.00 D). Linear mixed‐effects regression models explored the relationship between the spherical equivalent refractive error (SERE) and induced defocus. Results: Thirteen teenagers and young adults (ages 13–32 years, mean [standard deviation, SD] age = 22.8 [4.9] years) with high myopia (SERE −6.50 to −9.25 D) were tested. The treatment optic zone of the DF lens shifted retinal defocus by the expected −2.00 D, with a mean (SD) difference (DF–SV) of −2.21 (0.18) D for the inner treatment ring. Inclusion of the treatment optic had no significant impact on accommodative accuracy ( p = 0.51). Accommodative lags were larger at the nearer viewing distances, with lag increasing by approximately 0.30 D for every additional dioptre of SERE. Measured retinal defocus within the annular treatment zone was approximately −2.00 D at the foveal centre, 10° nasal and temporal and 20° nasal and reduced to −1.90 (0.57) D at 20° temporal. Conclusions: Relative to eyes with lower levels of myopia, the increased accommodative lags and more prolate retinas of highly myopic eyes reduced the myopic retinal defocus from the DF myopia control lens, while the treatment optical zones generated the combined effect of reducing hyperopic and introducing myopic retinal defocus relative to an SV correction.

Introduction: Previous literature has indicated an association between participant‐reported perceptions (e.g., ratings) of comfort, dryness and vision quality during soft contact lens wear. However, these reports do not account for participant‐ and lens‐specific factors which may impact the interpretation of these results. The purpose of this project was to quantify the association between these participant‐reported ratings while accounting for both participant‐ and lens‐specific factors. Methods: Participant‐reported ratings (scale 0–100) of comfort, dryness and quality of vision for 675 soft contact lens wearers (1207 eyes) were aggregated across 31 studies completed at Indiana University. Linear mixed‐effects regression modelling was performed on each outcome rating individually. Covariate‐adjusted models incorporated both participant‐ (e.g., age, sex) and lens‐related (e.g., lens material, edge and optics) factors. The models were statistically adjusted for the duration of lens wear in hours and cumulative days of exposure. Results: Consistent with estimates from covariate‐adjusted regression models, pairwise Spearman correlations [95% CI] between dryness and comfort ( r _s = 0.71, [0.69, 0.74]), vision quality and comfort ( r _s = 0.53, [0.49, 0.57]) and vision quality and dryness ( r _s = 0.49, [0.42, 0.54]) were all positive and had p < 0.001. Average participant‐reported ratings of comfort, dryness and vision quality decreased by ( b _s [95% CI]) = −0.81 [−1.15, −0.46] −0.34 [−0.67, 0.0005] and −0.90 [−1.19, −0.60] rating units, respectively, for each hour of lens wear. Conclusions: Significant positive associations were found between participant‐reported measures of comfort, dryness and vision quality during soft contact lens wear. The associations between these ratings and the participant‐ and lens‐related factors that drive them should be considered by clinicians and manufacturers when fitting and designing soft contact lenses.

Purpose: To evaluate the relative positions of modern soft contact lenses (SCLs) relative to the limbus/cornea and the pupil. Methods: Sixty images of the anterior eyes of 101 subjects were acquired over 10 s while participants fixated the centre of the camera lens located 33 cm in front of the eye in a well‐lit (300 lux) clinic. Custom validated image analysis software was used to locate the boundaries of the contact lenses, pupils and corneas (limbus). Horizontal and vertical relative positions of the contact lens, pupil and limbus were calculated from the fitted boundaries. Results: The mean (standard deviation) pupil and corneal diameters for all subjects were 3.84 mm, (0.83) and 11.97 mm (0.48), respectively. The mean [95% confidence interval] pupil centre was located 0.28 mm [0.26, 0.30] nasally and 0.07 mm [0.05, 0.10] superiorly to the corneal centre. Consistent with clinical observations, the contact lenses centred accurately relative to the corneal centre both nasally 0.04 mm [0.01, 0.07] and inferiorly −0.01 mm [−0.06, 0.03]. However, regardless of the eye, the contact lens was significantly ( p < 0.001) decentred relative to the pupil centre both temporally −0.23 mm [−0.26, −0.20] and inferiorly −0.08 mm [−0.12, −0.04]. Decentration magnitudes were significantly correlated between the right and left eyes. Conclusions: Spherical SCLs centred well on the cornea but temporally and inferiorly from the primary line of sight (pupil centre), due to the differences in the location of the pupil and corneal centres. Contrary to some previous reports, there was no evidence that lens optics or material affected lens centration significantly.

Purpose: Multizone contact lenses control myopia progression by proposed introduction of myopic defocus. This project investigated how much of the pupil area and how many dioptres of myopic defocus are introduced by different lens zone geometries with near‐ and off‐axis viewing. Methods: Ten young myopic adults (18–25 years) binocularly wore four soft contact lenses including a single vision (SV), concentric‐ring dual‐focus (DF), centre‐distance multifocal (MF) and a RingBoost™ (RB) multi‐zone design containing a combination of coaxial and non‐coaxial zones. A modified aberrometer captured aberrations and pupil sizes at four target vergences between −0.25 and −4.00 D (on‐axis) and across the central ±30° of the horizontal retina (off‐axis). Defocus was quantified as the difference between the measured refractive state and the target vergence within each zone of a multi‐zone design within the pupil and compared with that of equivalent zone areas of the SV lens. The percentage of the pupil containing myopic defocused light for each lens was calculated. Results: Defocus within the distance correction zones of multi‐zone lenses was similar to that of the SV lens. When viewing on‐axis at −0.25 D target vergence, on average 11% of the pupil was myopic with SV, whereas 62%, 84% and 50% of the pupil was myopic for the DF, MF and RB designs, respectively. At −4.00 D target vergence, all lenses exhibited a systematic decrease in the percentage of pupil area having myopic defocus (SV: 3%; DF: 18%; MF: 5% and RB: 26%). The off‐axis proportions were similar across multi‐zone lenses; however, multi‐zone lenses retained approximately 1.25–3.0× more myopic defocus than the SV lens. Conclusions: Subjects accommodated using the distance‐correction zones of multi‐zone lenses. Multi‐zone contact lenses introduced significant myopic defocus on‐axis and across the central ±30° retina. However, the magnitude and proportion of defocus were influenced by zone geometry, add power and pupil size.

Purpose: To evaluate the refractive impact of dual‐focus (DF) myopia control contact lenses (CLs) on accommodating young myopic adults. Methods: Phase 1: accommodative accuracy was assessed in 40 myopic participants. Phase 2: a subset of four subjects who demonstrated accurate accommodation and six who chronically underaccommodated were fitted with single vision (SV, Proclear 1 day) and centre‐distance DF myopia control CLs (MiSight 1 day) with approximately +2.00 D of additional power in two surrounding annular zones. While binocularly viewing high contrast characters at 4.00, 1.00, 0.50, 0.33, 0.25 and 0.20 m, aberrometry data were captured across the central ±30° of the horizontal retina. Local refractive errors were pooled for each area of the pupil covered by the central distance or first annular defocus zone of the DF CLs. Results: In the “good” accommodator group fitted with SV CLs, accommodative lags were generally absent except at the closest viewing distance (mean errors: −0.09 ± 0.22 D, −0.12 ± 0.26 D, −0.05 ± 0.37 D and +0.38 ± 0.54 D for −2.00, −3.00, −4.00 and −5.00 D target vergences, respectively) but significantly larger in the “poor” accommodating participants (+0.81 ± 0.21 D, +0.97 ± 0.27 D, +1.18 ± 0.39 D, +1.47 ± 0.55 D). For most viewing distances, hyperopic defocus observed in the region of the pupil covered by the first annular zone was replaced with myopic defocus when fitted with the DF CLs. Myopic defocus created by the first annular region was present across the central 30° of the retina. Conclusions: Some young adult myopes chronically experience high levels of hyperopic defocus when viewing near targets, which was replaced by myopic defocus in the annular part of the pupil covered by the treatment zones when fitted with a centre‐distance myopia control DF CL.