Measuring visual acuity and spherical refraction with smartphone screens emitting blue light

Introduction A periodical self-monitoring of spherical refraction using smartphones may potentially allow a quicker intervention by eye care professionals to reduce myopia progression. Unfortunately, at low levels of myopia, the far point (FP) can be located far away from the eye which can make interactions with the device difficult. To partially remedy this issue, a novel method is proposed and tested wherein the longitudinal chromatic aberration (LCA) of blue light is leveraged to optically bring the FP closer to the eye. Methods Firstly, LCA was obtained by measuring spherical refraction subjectively using blue pixels in stimuli shown on organic light-emitting diode (OLED) screens and also grey stimuli with matching luminance. Secondly, the visual acuity (VA) measured with a smartphone located at 1.0 m and 1.5 m and displaying blue optotypes was compared with that obtained clinically standard measurements. Finally, the spherical over refraction obtained in blue light with a smartphone was compared with clinical over-refraction with black and white (B&W) optotypes placed at 6 m. Results Mean LCA of blue OLED smartphone screens was −0.67 ± 0.11 D. No significant differences (p > 0.05) were found between the VA measured with blue optotypes on a smartphone screen and an eye chart. Mean difference between spherical over-refraction measured subjectively by experienced subjects with smartphones and the one obtained clinically was 0.08 ± 0.34 D. Conclusions Smartphones using blue light can be used as a tool to detect changes in visual acuity and spherical refraction and facilitate monitoring of myopia progression. (AU)

Measuring visual acuity and spherical refraction with smartphone screens emitting blue light.

INTRODUCTION: A periodical self-monitoring of spherical refraction using smartphones may potentially allow a quicker intervention by eye care professionals to reduce myopia progression. Unfortunately, at low levels of myopia, the far point (FP) can be located far away from the eye which can make interactions with the device difficult. To partially remedy this issue, a novel method is proposed and tested wherein the longitudinal chromatic aberration (LCA) of blue light is leveraged to optically bring the FP closer to the eye. METHODS: Firstly, LCA was obtained by measuring spherical refraction subjectively using blue pixels in stimuli shown on organic light-emitting diode (OLED) screens and also grey stimuli with matching luminance. Secondly, the visual acuity (VA) measured with a smartphone located at 1.0 m and 1.5 m and displaying blue optotypes was compared with that obtained clinically standard measurements. Finally, the spherical over refraction obtained in blue light with a smartphone was compared with clinical over-refraction with black and white (B&W) optotypes placed at 6 m. RESULTS: Mean LCA of blue OLED smartphone screens was -0.67 ± 0.11 D. No significant differences (p > 0.05) were found between the VA measured with blue optotypes on a smartphone screen and an eye chart. Mean difference between spherical over-refraction measured subjectively by experienced subjects with smartphones and the one obtained clinically was 0.08 ± 0.34 D. CONCLUSIONS: Smartphones using blue light can be used as a tool to detect changes in visual acuity and spherical refraction and facilitate monitoring of myopia progression.

Clinical validation of a novel smartphone application for measuring best corrected visual acuity

Purpose Personal mobile devices such as smartphones are proving their usefulness in ever more applications in tele-eyecare. An inconvenience and potential source of error in these past approaches stemmed from the requirement for the subjects to situate their devices at a distance. The present study aims to clinically validate best corrected visual acuity (BCVA) measures carried out by a novel smartphone application “vision.app” (VisionApp Solutions S.L.) using comparative statistics against clinical measurements. Materials and methods BCVA was measured in both eyes of 40 subjects using vision.app which displayed a black Landolt-C optotype with crowding on a white background, and utilized a 4 forced-choice procedure for the subjects to find (by means of swiping in either of four directions) the smallest optotype size they could resolve. Results were compared to BCVA measurements taken using a standard Snellen chart placed at 20 feet (6 m). Results The t-test revealed no significant differences between the app- and clinically-measured VA (p = 0.478 (OD) and 0.608 (OS)), with a mean difference between clinical and app measurements of less than one line of the eye chart (-0.009 logMAR (OD) and -0.005 logMAR (OS)). A limit of agreement for a 95% confidence interval of ± 0.08 logMAR for OD and OS was found. Conclusions The results show the potential use of a smartphone to measure BCVA at a handheld distance. The newly validated study results can hold major future advancements in tele-eyecare and provide eye care professionals with a reliable and accessible method to measure BCVA. (AU)

Conversion to Glaucoma in Pediatric Glaucoma Suspects.

PRCIS: In this retrospective review of pediatric glaucoma suspects, 11.5% of eyes progressed to glaucoma over an average of 6.5 years; eyes with ocular hypertension had an 18-fold increased risk of progression compared with eyes with suspicious disc appearance. PURPOSE: The purpose of this study was to describe the rate of progression to glaucoma of a large cohort of pediatric glaucoma suspects at a quaternary academic center. DESIGN: Retrospective case series. PARTICIPANTS: One thousand three hundred seventy-five eyes (824 individuals) followed as pediatric glaucoma suspects at the Wilmer Eye Institute between 2005 and 2016. METHODS: Retrospective study of pediatric patients monitored as glaucoma suspects at the Wilmer Eye Institute between 2005 and 2016. MAIN OUTCOME MEASURES: Progression to glaucoma, defined according to Childhood Glaucoma Research Network criteria or by surgical intervention; initiation of intraocular pressure-lowering therapy. RESULTS: One hundred fifty-eight (11.5%) eyes from 109 unique patients met the criteria for conversion to glaucoma during follow-up; rates of conversion ranged between 34.1% for eyes monitored for ocular hypertension, 16.2% for eyes with prior lensectomy, 12.1% for eyes monitored for other ocular risk factors, 2.4% for eyes with suspicious disc appearance, and 0.4% for eyes monitored for systemic risk factors. The first criterion met for conversion to glaucoma was ocular hypertension in 149 eyes (94.3%) and enlarged cup-to-disc ratio (CDR) in 9 eyes (5.7%); the most common second criterion met was the enlargement of CDR since initial presentation (45 eyes, 28.5%), surgical intervention (33 eyes, 20.9%), visual field changes (21 eyes, 13.3%), and asymmetric CDR change compared with fellow eye (20 eyes, 12.7%). The Kaplan-Meier survival curves across the different indications for being monitored as a glaucoma suspect significantly differed ( P <0.0001). Eyes being monitored for ocular hypertension had an 18-fold increased risk of conversion to glaucoma than those followed for suspicious disc appearance [hazard ratio (HR) 18.33, 95% CI, 10.05-33.41). Eyes monitored for prior lensectomy and for other ocular risk factors had a 6-fold and 5-fold increased risk of conversion to glaucoma than those followed for suspicious disc appearance, respectively (HR: 6.20, 95% CI, 3.66-10.51; HR: 5.43, 95% CI, 3.00-9.84). Eyes followed for ocular hypertension were nearly 4 times more likely to convert to glaucoma than those followed for prior lensectomy (HR: 3.72, 95% CI, 2.28-6.07). CONCLUSIONS: Eyes being followed as pediatric glaucoma suspects for ocular hypertension had higher rates of progression to glaucoma than eyes being monitored for prior lensectomy, other ocular risk factors, suspicious disc appearance, or systemic risk factors.

Clinical validation of a novel smartphone application for measuring best corrected visual acuity.

PURPOSE: Personal mobile devices such as smartphones are proving their usefulness in ever more applications in tele-eyecare. An inconvenience and potential source of error in these past approaches stemmed from the requirement for the subjects to situate their devices at a distance. The present study aims to clinically validate best corrected visual acuity (BCVA) measures carried out by a novel smartphone application "vision.app" (VisionApp Solutions S.L.) using comparative statistics against clinical measurements. MATERIALS AND METHODS: BCVA was measured in both eyes of 40 subjects using vision.app which displayed a black Landolt-C optotype with crowding on a white background, and utilized a 4 forced-choice procedure for the subjects to find (by means of swiping in either of four directions) the smallest optotype size they could resolve. Results were compared to BCVA measurements taken using a standard Snellen chart placed at 20 feet (6 m). RESULTS: The t-test revealed no significant differences between the app- and clinically-measured VA (p = 0.478 (OD) and 0.608 (OS)), with a mean difference between clinical and app measurements of less than one line of the eye chart (-0.009 logMAR (OD) and -0.005 logMAR (OS)). A limit of agreement for a 95% confidence interval of ± 0.08 logMAR for OD and OS was found. CONCLUSIONS: The results show the potential use of a smartphone to measure BCVA at a handheld distance. The newly validated study results can hold major future advancements in tele-eyecare and provide eye care professionals with a reliable and accessible method to measure BCVA.

Novel Virtual Vision Screening Program: Give Kids Sight Day 2020.

PURPOSE: To determine whether a low-technology novel virtual vision screening protocol can reliably screen pediatric visual acuity. METHODS: Give Kids Sight Day (GKSD), an annual out-reach program, aims to provide free vision screening and ophthalmic care to underserved children in Philadelphia, Pennsylvania. Children were screened virtually through the low-technology protocol. Based on screening results, 152 children were provided in-person eye examinations. Data from in-person examinations were compared to data from virtual screenings for 151 children who were seen in-person. RESULTS: Of 475 children screened virtually, 152 children were seen in-person for examination, and 151 children were included in the analysis. Results from 151 children (mean age: 10.7 years, age range: 5 to 18 years, 43% female, 28% speaking a non-English language) were reviewed. There was a moderate correlation (R = .64, P < .0001; n = 100 children) between screening and in-person visual acuity without refractive correction and a strong correlation (R = 0.82, P < .0001; n = 18 children) between screening and in-person visual acuity with refractive correction. Of the 140 children who were seen in-person, 133 children were provided glasses prescriptions. Seventeen children required a referral to a pediatric ophthalmologist for evaluation of ophthalmic conditions, most commonly strabismus (5.3%) and amblyopia (4%). CONCLUSIONS: The GKSD virtual visual acuity testing demonstrated good correlation with in-person visual acuity testing, supporting the virtual screening approach as a useful tool for future applications in widespread community vision outreach programs. Further studies are needed to refine virtual ophthalmic screening to optimize its applications in bridging the gaps in ophthalmic care. [J Pediatr Ophthalmol Strabismus. 2023;60(6):390-395.].

A comparison of visual outcomes in three different types of monofocal intraocular lenses.

AIM: To compare the visual outcomes (distance and near) in patients opting for three different types of monofocal intraocular lens (IOL) (Matrix Aurium, AcrySof single piece, and AcrySof IQ lens). METHODS: The present study is a cross-sectional analysis of secondary clinical data collected from 153 eyes (52 eyes in Matrix Aurium, 48 in AcrySof single piece, and 53 in AcrySof IQ group) undergoing cataract surgery (2011-2012). We compared near vision, distance vision, distance corrected near vision in these three types of lenses on day 15 (±3) post-surgery. RESULTS: About 69% of the eyes in the Matrix Aurium group had good uncorrected distance vision post-surgery; the proportion was 48% and 57% in the AcrySof single piece and AcrySof IQ group (P=0.09). The proportion of eyes with good distance corrected near vision were 38%, 33%, and 15% in the Matrix Aurium, AcrySof single piece, and AcrySof IQ groups respectively (P=0.02). Similarly, The proportion with good "both near and distance vision" were 38%, 33%, and 15% in the Matrix Aurium, AcrySof single piece, and AcrySof IQ groups respectively (P=0.02). It was only the Matrix Aurium group which had significantly better both "distance and near vision" compared with the AcrySof IQ group (odds ratio: 5.87, 95% confidence intervals: 1.68 to 20.56). CONCLUSION: Matrix Aurium monofocal lenses may be a good option for those patients who desire to have a good near as well as distance vision post-surgery.