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Purpose: To test the impact of professional management of soft contact lens wear on symptoms and ocular complications. Methods: Subjective symptoms and ocular complications of soft CL users who did not seek professional follow-up care (self-managed, SM), were compared to users who were prescribed CLs and their care professionally managed in optometry practices (PM), and to a control group of non-CL wearers. Habitual visual acuity, subjective dry-eye symptoms, and corneal abnormalities were assessed in all participants. CL wearers filled-out a usage habits questionnaire, and their CL fit was assessed. Outcomes were compared using Kruskal-Wallis and Chi Squared tests. Results: The SM, PM, and non-CL wearers cohorts included 127 (mean age:24.3±5.1, median:23, range:16–45 years,104 female), 132 (mean age:25.5±6.2, median:23, range:18–43 years,103 female), and 56 (mean age:22.3±3.5, median:21, range:18–39 years,36 female) participants, respectively. Meibomian gland dysfunction grade (p = 0.004, p<0.0001), limbal redness (both p = 0.04), corneal neovascularization (both p = 0.003), and papillary conjunctivitis (p<0.0001,p = 0.005) were significantly worse in SM CL wearers compared with both the non-CL wearers and PM CL wearers, respectively. Conjunctival staining was significantly worse in the SM cohort compared with the PM cohort (p = 0.01). 38.6% of the SM compared with 22.8% of the PM CL wearers, had an inappropriate refractive correction (p = 0.006). SM CL wearers wore CLs significantly more years (mean and median 1 year,p = 0.008), for more daily hours (mean and median of 2 hours,p<0.00001), and tended to nap or sleep with their CLs compared with the PM CL wearers (47 vs. 29,p = 0.02). The cohorts did not differ in their subjective symptoms. Conclusions: Complications are significantly more prevalent in SM CL wearers compared with PM CL wearers, and SM CL wearers tend to wear CLs with incorrect powers, and are less compliant with napping or sleeping with the CLs compared with PM CL wearers. These findings emphasize the importance of fitting, patient education and follow-ups in CL wearers. [ABSTRACT FROM AUTHOR]

This document is a response to a letter regarding the publication titled "Optimizing the Wilkins Egg and Ball Test: Overcoming Limitations for Accurate Astigmatism Detection." The authors of the response conducted a study to evaluate the effectiveness of the Wilkins' Egg and Ball Test in identifying uncorrected residual astigmatism and its impact on form symmetry perception. The study found no significant differences in the test results between two sessions for normal participants. The authors acknowledge the limitations of the test and suggest that further investigations are needed to improve its usefulness. [Extracted from the article]

Purpose: Assess the refractive states of donkeys and goats. Methods: Forty‐two donkeys and 28 goats were enrolled. The mean ± SD ages were 7.68 ± 7.33 years for donkeys and 4.26 ± 2.33 years for goats. Seven donkeys and one goat were <6 months old. Retinoscopy was performed in alert animals, following cycloplegia in goats but not in donkeys. Normality was determined using the Kolmogorov–Smirnov test. The two primary meridians and two eyes were compared using Pearson's correlation and paired Student's t–tests. The association between refractive states and age was examined using one‐way ANOVA in donkeys and a paired Student's t‐test in goats. One‐sample t‐tests were conducted to assess if the refractive error distributions were significantly different from "0". Results: The mean ± SD spherical equivalent (SE) refractive errors of the right and left donkey eyes were −0.80 ± 1.03 D and −0.35 ± 0.95 D, respectively. The majority (86%) of the donkeys had an astigmatic refraction and eight (19%) had anisometropia. The mean SE refractive errors of the right and left goat eyes were −0.15 ± 1.1 D and −0.18 ± 1.2 D, respectively. The majority (54%) of the goat eyes had an astigmatic refraction and five (18%) had anisometropia. The right and left eye SE refractive errors were positively correlated in both species (both p =.9). Age was not correlated with refractive error in both donkeys (p =.09) and goats (p =.6). Conclusions: Both goats and donkeys are emmetropic. [ABSTRACT FROM AUTHOR]

Two case studies in the literature report on patients with infantile nystagmus (IN) who preferred to read text that is oriented vertically rather than horizontally. The current study systematically evaluated the effect of text orientation (-60 to +90 deg with respect to horizontal) on reading speed in nine individuals with IN associated with albinism at Hadassah Academic College (HAC), seven individuals with IN at the University of Houston (UH), and a total of 17 normal control observers. Observers at HAC read 40-character passages of Hebrew text from standardized 2nd grade level reading material and observers at UH read MNRead acuity chart sentences. Letter size was two to six lines larger than each observer's measured visual acuity. In both individuals with IN and normal observers reading speed was fastest for horizontally oriented text and decreased for other orientations. However, reading speed decreased significantly more for non-horizontally orientated text in the observers with IN, compared to controls. In general, it is recommended that to achieve best reading performance patients with IN read horizontally oriented text. [ABSTRACT FROM AUTHOR]

Purpose: A primary task of the eye care professional is determining the refraction, or optical correction, of a patient. The duochrome red-green test is a standard tool for verification of the final refraction. Traditionally, it is recommended for use both prior to and subsequent to determining the cylindrical or astigmatic component of the refraction. In order for it to be effective when used before correcting the cylinder it is necessary that the COLC (Circle of Least Confusion) be on the retina. This study examined whether it is necessarily true that the duochrome response in uncorrected astigmatism will be as trust-worthy as it is with corrected cylinders. Methods: The red-green examination was performed monocularly under the following three conditions: a. fully corrected refraction for the subgroup of eyes that had spherical refractions and for the subgroup of eyes with sphero-cylindrical refractions. b. best sphere-only correction without cylinder correction in sphero-cylindrical eyes c. an induced cylinder error in spherical eyes. The interval between the last “red” response and the first “green” response for the right eyes as a group and separately for the physiological cylinder and induced cylinder correction sub-groups was calculated and compared using a paired, two-tailed t-test. Results: The intervals between “red” and “green” responses were not significantly different in the population as a whole and in the uncorrected physiological cylinder and induced cylinder subgroups examined. Conclusion: Based on the finding that the interval of red-green equality with fully corrected cylinder and without the cylindrical correction are not significantly different, the red-green duochrome test can indeed be used both before and after cylindrical correction. [ABSTRACT FROM AUTHOR]

Purpose: The inter‐session repeatability (ISR), inter‐examiner reproducibility (IER) and within‐subject variability (WSV) of the Cobra HD fundus camera meibographer were examined in participants with and without dry eye symptoms. Methods: Symptoms were determined based on Ocular Surface Disease Index scores (≥13 being considered symptomatic), and subgroups were compared using the Mann–Whitney U‐test. Images of meibomian glands (MGs) from the upper and lower right eyelids were captured by two examiners on the same day (S1) to determine IER. One examiner repeated the measurements on a second day (S2) to obtain the ISR. ISR, IER and WSV were calculated using Friedman, correlation tests and Bland and Altman analyses with mean differences (md) and 95% confidence intervals (CIs), within‐subject standard deviations (Sw) and intra‐class correlation coefficients (ICC). Results: The ISR experiment included 72 participants (mean age: 23 ± 5 years, range: 19–43, 36 symptomatic). Mean MG loss of the upper (S1: 13.5 ± 9.5%, S2: 12.8 ± 8.5%) and lower eyelids (S1: 7.5 ± 6.9%, S2: 7.3 ± 6.3%) was not significantly different between sessions for all participants, symptomatic and asymptomatic subgroups for both eyelids. The ISR Sw for the upper and lower eyelids was 1.3% and 1.0%; md was 0.7 ± 3.5% (CI:−6.25% to 7.62%) and 0.1 ± 2.1% (CI: −3.94% to 4.17%), respectively. The IER experiment included 74 participants (mean age: 23 ± 5 years, range: 19–43, 37 symptomatic). Mean MG loss of the upper (Examiner 1: 12.7 ± 8.2%, Examiner 2: 13.1 ± 8.0%) and lower eyelids (Examiner 1: 7.0 ± 6.2%, Examiner 2: 7.4 ± 6.2%) was not significantly different between examiners for all participants, symptomatic and asymptomatic subgroups for both eyelids. The IER ICC values were >0.86 for all conditions, Sw was 1.3% and 1.2%, with a md of −0.4 ± 3.2% (CI: −6.65% to 5.90%) and −0.4 ± 2.9% (CI: −6.15% to 5.31%), respectively. The WSV Sw values were <1.4%, and ICC values were >0.89 for both eyelids, examiners and experimental sessions. Conclusions: The Cobra HD fundus camera demonstrates good repeatability, reproducibility and low WSV, and is a reliable clinical instrument for meibography. [ABSTRACT FROM AUTHOR]

Abstract: Several previous studies reported differences when stereothresholds are assessed with local-contour stereograms vs. complex random-dot stereograms (RDSs). Dissimilar thresholds may be due to differences in the properties of the stereograms (e.g. spatial frequency content, contrast, inter-element separation, area) or to different underlying processing mechanisms. This study examined the transfer of perceptual learning of depth discrimination between local and global RDSs with similar properties, and vice versa. If global and local stereograms are processed by separate neural mechanisms, then the magnitude and rate of training for the two types of stimuli are likely to differ, and the transfer of training from one stimulus type to the other should be minimal. Based on previous results, we chose RDSs with element densities of 0.17% and 28.3% to serve as the local and global stereograms, respectively. Fourteen inexperienced subjects with normal binocular vision were randomly assigned to either a local- or global- RDS training group. Stereothresholds for both stimulus types were measured before and after 7700 training trials distributed over 10 sessions. Stereothresholds for the trained condition improve for approximately 3000 trials, by an average of 0.36±0.08 for local and 0.29±0.10 for global RDSs, and level off thereafter. Neither the rate nor the magnitude of improvement differ statistically between the local- and global-training groups. Further, no significant difference exists in the amount of improvement on the trained vs. the untrained targets for either training group. These results are consistent with the operation of a single mechanism to process both local and global stereograms. [ABSTRACT FROM AUTHOR]

Abstract: Perceptual learning is a training induced improvement in performance. Mechanisms underlying the perceptual learning of depth discrimination in dynamic random dot stereograms were examined by assessing stereothresholds as a function of decorrelation. The inflection point of the decorrelation function was defined as the level of decorrelation corresponding to 1.4 times the threshold when decorrelation is 0%. In general, stereothresholds increased with increasing decorrelation. Following training, stereothresholds and standard errors of measurement decreased systematically for all tested decorrelation values. Post training decorrelation functions were reduced by a multiplicative constant (approximately 5), exhibiting changes in stereothresholds without changes in the inflection points. Disparity energy model simulations indicate that a post-training reduction in neuronal noise can sufficiently account for the perceptual learning effects. In two subjects, learning effects were retained over a period of six months, which may have application for training stereo deficient subjects. [Copyright &y& Elsevier]

Perceptual learning is a training induced improvement in performance. Mechanisms underlying the perceptual learning of depth discrimination in dynamic random dot stereograms were examined by assessing stereothresholds as a function of decorrelation. The inflection point of the decorrelation function was defined as the level of decorrelation corresponding to 1.4 times the threshold when decorrelation is 0%. In general, stereothresholds increased with increasing decorrelation. Following training, stereothresholds and standard errors of measurement decreased systematically for all tested decorrelation values. Post training decorrelation functions were reduced by a multiplicative constant (approximately 5), exhibiting changes in stereothresholds without changes in the inflection points. Disparity energy model simulations indicate that a post-training reduction in neuronal noise can sufficiently account for the perceptual learning effects. In two subjects, learning effects were retained over a period of six months, which may have application for training stereo deficient subjects. [ABSTRACT FROM AUTHOR]

Introduction: Soft contact lenses may be a good alternative for early‐stage keratoconus (KC) patients who do not tolerate rigid gas permeable (RGP) lenses due to ocular discomfort or complications. This prospective study compared outcomes obtained after 2 weeks of wearing two types of soft silicone hydrogel contact lenses for keratoconus that varied in their diameter and central thickness (cc). Methods: Patients with Amsler–Krumeich grades I or II KC were fitted with small‐diameter (14.2 or 14.8 mm) SoftK (SD‐SoftK, cc = 0.48 mm) and large‐diameter (17 mm) SoftK (LD‐SoftK, cc = 0.60 mm) lenses, each worn for 2 weeks in a crossover design. Low (10%;10VA) and high (100%;100VA) contrast visual acuity, contrast sensitivity (CS, Pelli‐Robson), higher order aberrations (HOAs, Visionix Vx130), the number of trial lens modifications during fitting and the subjectively preferred lens were compared using Friedman tests with post‐hoc analysis. Results: Forty eyes (N = 20, 10 males, mean age: 39.0 ± 9.9 years, range: 23–55 years) were examined. Their habitual median (interquartile1, interquartile3) 10VA (LogMAR), 100VA (LogMAR) and CS (LogCS) were 0.52 (0.30, 0.50), 0.14 (0.10, 0.15) and 1.35 (1.35, 1.50), respectively. For the SD‐SoftK condition, the values were 0.23 (0.17, 0.30), 0.02 (0.00, 0.05) and 1.50 (1.50, 1.65), respectively. For the LD‐SoftK condition, the respective values were 0.36 (0.27, 0.44), 0.09 (0.05, 0.13) and 1.50 (1.50, 1.60). SD‐SoftK lenses significantly improved 10VA compared with habitual and LD‐SoftK. SD‐SoftK also significantly improved CS compared with habitual, but not LD‐SoftK. LD‐SoftK significantly improved spherical aberration compared with uncorrected (0.03 ± 0.10 μ vs. 0.07 ± 0.13 μ) but not SD‐SoftK (0.04 ± 0.07 μ). Both lenses required a mean of 1.5 modifications prior to final lens fitting. Fewer adverse events were seen with SD‐SoftK (N = 3) compared with LD‐SoftK (N = 8), and 75% of participants preferred SD‐SoftK lenses. Conclusion: SD‐SoftK lenses were preferred by 75% of subjects, were associated with fewer adverse events and significantly improved 10VA compared with LD‐SoftK lenses. SD‐SoftK lenses also significantly improved CS compared with the habitual correction, but this did not differ significantly from the LD‐SoftK lenses. [ABSTRACT FROM AUTHOR]

Purpose: Astigmatism blurs the retinal image of a circular spot along a particular orientation rendering it an elliptical shape. Astigmatic patients demonstrate adaptation to residual astigmatic blur that may affect their discrimination between oval and circular targets. The Wilkins Egg and Ball Test (WEBT) was created to detect altered visual perception due to residual astigmatic blur by discriminating a circle within a row of oval elements. This prospective, cross-sectional study examined the utility of WEBT in detecting uncorrected residual astigmatism on the perception of form symmetry in astigmatic and keratoconic participants as well as normal participants with induced astigmatism at four primary meridians. Methods: The mean search time (sT) and number of errors (noE) of 33 non-astigmatic controls (mean age: 24± 5, range: 18– 43, 6 males), 23 astigmatic participants (mean age: 36± 12, range: 18– 43, 6 males) and 13 keratoconic participants (N=22 eyes, mean age: 36± 12, range: 18– 58, 6 males) were measured under baseline, and 2.00 DC induced cylinder at four primary meridians, and for uncorrected, spherical-correction only, and fully corrected conditions, respectively. Mean sT and noE were converted to Z-scores, combined for each condition, and compared using repeated measures ANOVA with post-hoc analysis. Results: Combined Z-scores for the controls were significantly worse (p< 0.001) for all induced cylinder conditions. The induced 180° condition was significantly better than 45° and 90° conditions (p=0.04), but not the 135° condition. For both astigmatic and keratoconic cohorts, Z-scores of the uncorrected condition were significantly worse than the fully corrected condition (both p< 0.01), but the fully corrected and spherical-only conditions did not differ significantly (p=0.06 and p=0.05, respectively). Conclusion: In accommodating young adults, WEBT detected altered visual perception due to overall blur, and moderate-high amounts of uncorrected induced astigmatism and keratoconus, but is not useful as a tool for detection of altered visual perception due to small residual astigmatic blur. [ABSTRACT FROM AUTHOR]

Introduction: This study investigated the equivocal association between contact lens (CL) wear and meibomian gland dysfunction (MGD) by comparing the morphological, functional and subjective outcomes of CL wearers versus control, non‐CL wearers. CL wearers were examined as two cohorts based on the annual attendance of follow‐up visits (FLU—attended these visits, whereas non‐FLU did not). Methods: Habitual logMAR visual acuity, invasive and non‐invasive tear break‐up time, Schirmer test, Efron grading scales, meibum quality score (MQS), meibum expressibility score (MES), meibomian gland (MG) loss, lid margin abnormalities and subjective dry eye (DE) symptoms were assessed. Results: Of the 128 participants, 31 were in the FLU cohort, 43 were in the non‐FLU cohort and 54 were controls (mean ages: 22.2 ± 3.1, 23.0 ± 4.6 and 22.3 ± 3.5, respectively). Non‐FLU CL wearers had more symptoms than controls (3.7 ± 2.4 vs. 2.3 ± 2.1, p < 0.01). Morphologically, FLU (16.9 ± 8.8%, p = 0.02) and non‐FLU (18.6 ± 11.3%, p = 0.001) had more MG loss than controls (11.2 ± 6.8%). Functionally, FLU (0.6 ± 0.7, p = 0.01) and non‐FLU (0.8 ± 0.9, p = 0.001) had worse MES than controls (0.2 ± 0.5). FLU and non‐FLU were both associated with corneal staining (odds ratio [OR] = 3.42, 95% CI: 1.16–10.11, p = 0.03 and OR = 5.23, 95% CI: 1.89–14.48, p = 0.001, respectively) and MG loss (OR = 10.47, 95% CI: 1.14–96.29, p = 0.04 and OR = 16.63, 95% CI: 1.96–140.86, p = 0.01, respectively). Non‐FLU CL wear was also associated with abnormal MQS (OR = 12.87, 95% CI: 1.12–148.41, p = 0.04), conjunctival staining (OR = 12.18, 95% CI: 3.66–40.51, p < 0.001) and lid margin telangiectasia (OR = 3.78, 95% CI: 1.55–9.21, p = 0.003). MGD was three times more prevalent in CL wearers (12%) than in controls (4%). Conclusions: Both CL‐wearing cohorts demonstrated significantly more MG abnormalities than controls though the difference was not clinically significant. Non‐FLU CL wearers had more DE symptoms. Non‐FLU CL wear is an independent predictor for more abnormalities than FLU CL wear, emphasising the importance of follow‐ups. [ABSTRACT FROM AUTHOR]

Purpose Motor vehicle accidents (MVAs) are a pandemic associated with human suffering and a burden to national economies. Whiplash-associated disorders (WADs) after MVAs are associated commonly with disability claims, many of which are related to vision. Convergence insufficiency (CI) leads to visual disability associated with symptoms of ocular discomfort. We examined the incidence of symptoms and findings consistent with CI in a cohort of patients after MVA-related WAD compared with age-matched control participants. Design Prospective cohort study. Participants Patients with WAD after MVA were recruited from the Orthopedic Emergency Department between July 2014 and March 2017. Control participants were recruited among hospital personnel and relatives of WAD patients. Methods The Convergence Insufficiency Symptom Survey (CISS) questionnaire was completed by each participant, followed by a detailed visual examination including measurements of distance and near best-corrected Snellen visual acuity, distance and near cover test, Randot stereopsis, Maddox distance and Maddox-Thorington near heterophoria, near point of convergence, base-out step fusional reserves, and amplitude of accommodation using the push-away method. Main Outcome Measures The CISS score and binocular measure findings of CI were recorded and analyzed using Student's t test, the chi-square test, and multiple logistic regression adjusted for age and gender. Results A pathologic CISS score of 16 or more occurred in 26 of 57 WAD patients (45.6%) compared with 6 of 39 control participants (15.4%; P = 0.002). Absolute CISS score was higher in the WAD group compared with the control group (15.3±10.0 vs. 7.7±7.7; P < 0.001). Findings consistent with CI occurred in 7.0% of WAD patients and 7.7% of control participants ( P = 0.90). Conclusions Visual symptoms suggestive of CI were reported more frequently among WAD patients compared with control participants, yet the incidence of examination findings indicating weakness of convergence was not increased. The discrepancy between subjective and objective measures of CI in WAD patients versus control participants stresses the importance of training healthcare personnel to assess disability using objective, validated standards of examination. [ABSTRACT FROM AUTHOR]

Purpose To determine the prevalence of choroidal naevi in a healthy population using an ultra-wide scanning laser ophthalmoscope which can capture up to a 200° field of view of the retina, without pupil dilation. Methods Subjects were recruited from a college population. Each subject underwent an eye examination that included retinal and choroidal imaging using the Optos scanning laser ophthalmoscope and completed a self-administered questionnaire. Univariate and multivariate regression analysis were performed to identify associated factors with choroidal naevi. Results The Optomap images of 406 participants (mean age 23.5 ± 4.4) were analysed. Thirty-nine subjects (10%) presented with at least one naevus in one eye, and multiple naevi were observed unilaterally in eight subjects. Drusen were noted in only one eye. The mean naevus diameter was 2.38 mm (±2.07). Prevalence was not associated with either eye colour, time spent outdoors, visual impairment, or ethnic group, but was significantly associated with male gender ( OR 2.41, p = 0.009), blond/red hair colour ( OR 2.42, p = 0.037), skin that neither burns nor tans ( OR 2.8, p = 0.02) and habitual sunglasses use ( OR 0.33, p = 0.002). Conclusions A higher prevalence of choroidal naevi was detected in this college population compared to other population-based studies. This is likely due to the use of an ultra-wide field scanning laser ophthalmoscope which provides up to 200° of the fundus. The naevi were associated with several factors. [ABSTRACT FROM AUTHOR]

Achromatopsia is an inherited retinal disease characterized by loss of cone photoreceptor function. Day blind CNGA3 mutant Improved Awassi sheep provide a large animal model for achromatopsia. This study measured refractive error and axial length parameters of the eye in this model and evaluated chromatic pupillary light reflex (cPLR) testing as a potential screening test for loss of cone function. Twenty-one CNGA3 mutant, Improved Awassi, 12 control Afec-Assaf and 12 control breed-matched wild-type (WT) Awassi sheep were examined using streak retinoscopy and B-mode ocular ultrasonography. Four CNGA3 mutant and four Afec-Assaf control sheep underwent cPLR testing. Statistical tests showed that day-blind sheep are significantly more myopic than both Afec-Assaf and WT Awassi controls. Day-blind sheep had significantly longer vitreous axial length compared to WT Awassi (1.43 ± 0.13 and 1.23 ± 0.06 cm, respectively, p < 0.0002) and no response to bright red light compared to both controls. Lack of response to bright red light is consistent with cone dysfunction, demonstrating that cPLR can be used to diagnose day blindness in sheep. Day-blind sheep were found to exhibit myopia and increased vitreous chamber depth, providing a naturally occurring large animal model of myopia. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented regarding the presence of congenital hypertrophy of the retinal pigment epithelium (CHRPE) on a healthy college population in Israel.