Comparison of three instruments for heterophoric testing

Objective To discuss the differences in the response AC/A between progressive myopes,stable myopes and emmetropes,and to try to analyze the causes for the differences.Methods Fifty-one subjects (17 progressive myopes,17 stable myopes and 17 emmetropes) participated in the study.The accommodative response and heterophoria were measured under 9 different stimulus states.And the response AC/A and accommodative error index (AEI) were calculated.A one-way ANOVA was used to analyze the data.Results There was a significant difference in the response AC/A between progressive myopes,stable myopes and emmetropes (F=4.051,P＜0.05).Progressive myopes had a higher AC/A ratio than stable myopes and emmetropes.No significant differences were found in the AEI values for the three refractive groups (F=2.579,P＞0.05).At high stimulus levels (3.21-4.12 D),progressive myopes showed more esophoria than stable myopes and emmetropes,but significant-differences were found between the three refractive groups only at the 4.12 D level (F=3.828,P＜0.05).Conclusion Progressive myopia has a higher response AC/A and more esophoria than stable myopes and emmetropes,which suggests that high AC/A and large esophoria may be the risk factors for myopia progression.And the large esophoria may be the reason for the high AC/A ratio. Key words: Myopia; AC/A ratio; Esophoria; The AEI value

Objective To investigate the function of accommodation in adolescent myopia and study the differences of accommodation between the dominant and non-dominant eye.Methods Ninety-five subjects (50 myopes,20 emmetropes,25 hyperopes)aged 6～15 years,participated.The accommodative lag and amplitude of accommodation were assessed with their refractive errors corrected.The accommodative lags were assessed using MEM dynamic retinoscopy at 40 cm reading distance.Results 1 there were no significant differences of amplitude of accommodation and accommodative lag between the myopia group and emmetropia group.The differences of amplitude of accommodation between the myopia group and hyperopia group were significant(t=2.21,P=0.03＜0.05;t=2.83,P=0.006＜0.05).2 The difference of accommodative lag between the dominant eye(0.73±0.31)D and non-dominant eyes(0.81±0.38)D in myopia group was significant.3 The accommodative lag of dominant eyes Was(0.68±0.36)D and it of non-dominant eyes Was(0.75±0.34)D,the difference was significant(t=2.06,P=0.042＜0.05,n=95).There was no significant difference between the amplitude of accommodation of dominant eye(12.9±3.09)D and non-dominant eyes(12.6±3.09)D.Conclusion There were no significant differences ofaccommodative lag and amplitude ofaccommodation between the adolescent myopes and emmetropes.The accommodative lag of dominant eyes Was less than it of the non-dominant eye in adolescent.The differences in accommodative function of dominant and non-dominant eyes should be mentioned. Key words: Adolescent; Myopia; Accommodation

Binocular interaction for a central field was studied with transient scalp visual evoked cortical potentials (VECPs) using two light-emitting-diodes. VECPs were obtained for binocular and monocular visions with dominant and non-dominant eyes, and arithmetical sums of monocular VECPs with dominant and non-dominant eyes were calculated. Amplitude and latency of remarkable initial three peaks were tested with the multivariate analysis of variance. Significant differences were noted among the four VECPs. Pairwise comparisons showed that (1) the amplitude of the first peak for the binocular VECPs was larger than that for the monocular VECPs but smaller than that for the sum-VECPs; the latency of the first peaks for the binocular VECPs were earlier than that for the monocular VECPs with the non-dominant eye; (2) the amplitude of the first negative peak for the sum-VECPs was larger than that for the binocular VECPs, and the peak latency for the sum-VECPs showed later than that for the binocular VECPs; (3) the amplitude of the second positive peak for the binocular VECPs and monocular VECPs with the dominant eye was larger than that with the non-dominant eye, but smaller for the binocular VECPS than that for the sum-VECPs; the latency for the binocular VECPs showed earlier than that for the monocular VECPs with the dominant eye and for the sum-VECPs. Binocular suppression was noted in amplitude for the three peaks and binocular facilitation was noted in latency for the latter two peaks.

Purpose : The purpose of this study was to measure binocular accommodative response when hyperopic and myopic anisometropia were induced on non-dominatn eye.Methods : Twenty participants (mean age: 24.05±1.73) who had corrected visual acuity more than 0.0 logMAR and no eye disease or systemic disease were recruited. The contact lenses with +1.00, +2.00, -1.00, -2.00 D were monocularly worn on non-dominant eye. The accommodative responses were measured by a binocular open-field autorefractometer when participant fixates target (accommodative stimulus) at 300, 40, and 20 cm.Results : As the accommodative stimulus distance decreased, the amount of accommodative response increased in both eyes (p<0.050). There was significant difference of accommodative responses by different degree of anisometropia (p<0.050). When –2.00 D hyperopic anisometropia was induced, both eyes showed the highest accommodative responses at 40 cm (dominant eye 1.50±0.11 D, non dominant-eye 1.71±0.09 D). When comparing accommodative responses by the type of anisometropia, there was a significant differences in both the dominant and nondominant eyes at 20 cm when inducing 1.00 and 2.00 D in myopic and hyperopic anisometropia (p<0.050). At 40 cm, there was a significant differences in both the dominant and non-dominant eyes when inducing 1.00 in myopic and hyperopic anisometropia (p<0.050). In addition it showed that the higher the degree of myopia and hyperopia, the higher the difference in accommodative response on both eyes and the difference was significant between 40 and 20 cm (p<0.050).Conclusion : There is a difference in the amount of accommodative response between dominant and non-dominant eye when anisometropia was induced. Regardless of the type, the environment that causes the difference in the amount of accommodative response between both eyes causes eye fatigue, so to prevent such a situation, not only the examination on accommodative response of both eyes, but also regular and continuous management is necessary. Also, a prescription for glasses and addition considering the difference between the two eyes is required.

Non-dominant eye responses in the dorsal lateral geniculate nucleus of the cat: an intracellular study

BackgroundThe ability of physical therapists (PTs) to accurately identify and reliably measure phoria/tropia is critical in the differential diagnosis of individuals with acute vestibular syndrome and concussion/mild traumatic brain injury.ObjectivesTo determine if PTs may reliably measure phoria and to determine the reliability of two dissociating tests of phoria, the prism neutralized Maddox rod test and modified Thorington method, in normal adults with artificially created phoria.MethodsThirty adults (mean age 24.87 ± 4.74 years) were randomly assigned to wear trial lenses (1, 2, 4, or 6 pd prism left, plain glass right) to create phoria. In sitting and supine, phoria was measured using prism neutralized Maddox rod test and modified Thorington method. Mean, SD, and range of first neutral endpoint were calculated for each examiner. Percentage of trials in agreement (≤ 2 and 4 pd); comparisons within the linear mixed effects regression model; and inter‐rater reliability between examiners was calculated with the intra‐class correlation coefficient (ICC).ResultsParticipants underwent 20 measurements by each examiner. Trial agreement between examiners was 74% (range 13%‐100%) in horizontal and 91% (range 63%‐100%) in vertical plane. Maddox rod test had significantly different means between two examiners (P < .05). Modified Thorington test had no significant difference. The Maddox rod test had a significant examiner main effect, examiner 2 always scored lower. Inter‐rater correlation coefficient for each test was significant at level of P < .01 (ICC ≥ 0.67 ≤ 0.94) except for modified Thorington test in supine, horizontal plane with P < .05 (ICC ≥ 0.38).ConclusionPTs may reliably measure artificially created phorias using prism neutralized Maddox rod test and modified Thorington method.

To evaluate visual outcomes after bilateral implantation of the RayOne EMV intraocular lens with targeted micromonovision. Southend Private Hospital, Westcliff on Sea, United Kingdom. Retrospective cohort. 50 patients (100 eyes) were assessed at 12 to 18 months postoperatively. Emmetropia was targeted in the dominant eye and myopia of -0.50 to -1.00 diopter (D) in the nondominant eye. Uncorrected (UDVA) and corrected (CDVA) distance visual acuity was assessed monocularly and binocularly at distance (6 m), intermediate (70 cm), and near (40 cm). Defocus was assessed from +1.50 to -4.00 D monocularly and binocularly. Contrast sensitivity was assessed using a computerized Pelli-Robson chart. Mean spherical equivalent was -0.05 ± 0.34 D and -0.91 ± 0.60 D in the dominant and nondominant eyes, respectively. UDVA was significantly different in the dominant (0.09 ± 0.10 logMAR) and nondominant (0.31 ± 0.18 logMAR) eyes ( P < .01). CDVA, distance corrected intermediate VA (DCIVA), and distance corrected near VA (DCNVA) were similar between eyes. However, significant differences were found between binocular uncorrected intermediate VA (UIVA) (0.16 ± 0.11 logMAR) and DCIVA (0.31 ± 0.11 logMAR) ( P < .01) and between binocular uncorrected near VA (UNVA) (0.30 ± 0.17 logMAR) and DCNVA (0.50 ± 0.19 logMAR) also ( P < .01). The nondominant eye shows superior acuity eye in both UIVA ( P < .01) and UNVA ( P < .01). Contrast sensitivity showed no significant difference between eyes ( P = .06). Significant improvement binocularly compared with monocularly was seen through imposed defocus -0.50 to -2.50 D. The RayOne EMV with micromonovision is a reliable method for improving intermediate and near VA, by increasing the range of focus without compromise of distance acuity or contrast sensitivity.

목적: 본 논문에서는 3D display 장치를 활용하여 사위량을 측정하는 새로 고안된 사위검사법이 기존의 사위검사법을 분석 및 비교하여 어떠한 차이가 있는지 알아보았다. 방법: 실험은 마독스로드법(Maddox rod), 폰 그라페법(von Graefe) 등 기존 사위검사법 2가지와 새로 고안한 3D편광사위검사법으로 사위량을 측정하였다. 3D편광사위검사법은 기존의 편광렌즈를 활용한 사위검사와 달리 편광렌즈와 시야조리개를 사용하여 완전융합사위제거 상태로 사위량을 측정한다. 이를 위해 세 가지 사위검사법에 모두 사용 가능하도록 새로 고안된 사위검사시표와 이를 표시하는 3D display 장치를 활용하였다. 피검사자는 남녀 12명이며, 사위검사에 영향을 줄 수 있는 사위검사순서를 고려하여 3가지 사위검사의 모든 경우의 순서를 고려하여 세 가지 실험 1세트-1회를 기준으로 총 6회의 실험을 하여 총 72세트의 표본을 얻었다. 양안융합의 제거를 위해 실험조건을 어둡게 했으며, 시표의 RGB색상코드(RGB color code)를 기준으로 (20, 20, 20), 실험실의 조명은 10 lx 이하를 유지하였다. 결과: 실험결과 72세트의 표본 중, 외사위 30세트, 내사위 12세트, 정위 30세트로 분류되었다. 먼저 검사순서에 의한 분석 결과 실험에 영향을 주지 않았다. 사위량의 비교분석 결과, 가장 높은 사위량이 검출된 검사법은 마독스로드법이었으며 3D편광사위검사법이 가장 낮은 사위량이 검출되었다. 각 검사법의 사위량은 차이를 보이고, paired t-test 분석 결과 통계적으로 유의하여 사위량이 3D편광사위검사법<폰 그라페법<마독스로드법 순의 경향으로 검출될 확률이 높다. 결론: 새로 고안된 3D편광사위검사법은 기존 사위검사법보다 상대적으로 낮은 사위량이 검출되었으나 통계적으로 유의한 차이를 보인다. 새로 고안된 3D편광사위검사법은 피검사자의 자연스러운 융합제거와 비교적 안정적인 안위 상태에서 이루어진 검사로 사위량을 검사하는 점에서 의의가 있다. Purpose: This study compared the quantity of phoria for distance by new method with that by existing methods. Methods: For this study, it was selected to two existing phoria measurements, von Graefe and Maddox rod. And new method named "3D polarizing phoria measurement" was designed to measure the quantity of phoria using polarizing glasses and 3D display. Unlike existing measurement using polarized lens, newly considered method measured the quantity of phoria in condition removed perfect binocular fusion using field stop on apparatus and polarized lens. For using new method for distance, it was developed a phoria test chart. It supports three kinds of phoria measurements. Subjects were 12 (male 6, female 6). They had three phoria tests (1 sets) including new method. It was considered the effect of experimental order, so we tested all cases about experimental order. The number of cases was 6 sets, and the sample size in this experiment was 72 sets. For removing binocular fusion, lighting of the laboratory that was below 10 lx and the background color of phoria test chart was dark, RGB=(20, 20, 20). Results: Subjects were sorted into three groups. Samples with exophoria and orthophoria were 30 sets each, and those with esophoria were 12 sets. The quantity of phoria measured three tests differ from each other like "newmethod < von Graefe < Maddox rod", and there were statistically significant difference each other. Conclusions: This study has great significance in the sense that new method was the measurement with naturally removing binocular fusion without dizziness during the tests.

Static monocular visual cues can decrease the vestibular-evoked balance response at low frequencies

Macular thickness, retinal thickness, and optic disk parameters in dominant compared with nondominant eyes

To investigate the outcomes of unilateral Supracor treatment to enhance near vision while maintaining good distance vision in hyperopic eyes. This prospective interventional study includes consecutive hyperopic patients with presbyopia. All eyes underwent femtosecond laser-assisted in situ keratomileusis treatment for hyperopia with an additional Supracor multifocal treatment algorithm in nondominant eyes. Monocular and binocular uncorrected and spectacle-corrected distance visual acuity (UCDVA and SCDVA), monocular and binocular uncorrected near visual acuity (UNVA), and distance-corrected near visual acuity at 40 cm and high-order aberration changes and complications were evaluated for 6 months. Sixty-four patients with a mean age of 51.91 ± 3.64 were enrolled. After 6-month follow-up, the mean binocular UCDVA and UNVA were 0.03 ± 0.05 and 0.04 ± 0.06 logMAR, respectively. UCDVA (logMAR) of nondominant and dominant eyes was 0.30 ± 0.18 and 0.03 ± 0.05, respectively. Preoperative and postoperative mean ± standard deviation manifest refraction spherical equivalent was +1.84 ± 0.75 and -0.48 ± 0.57, respectively, in nondominant eyes and +1.77 ± 0.69 and +0.12 ± 0.33, respectively, in dominant eyes. No complications were observed. Supracor procedure in nondominant eyes may improve functional near, intermediate, and distance vision without significant photic phenomena in presbyopic patients with low and moderate hyperopia.

Objective To study the visual function of the eyes with binocular phacoemulsification and single-focus intraocular lens implantation designed by monovision principle. Methods Forty-two patients (84 eyes) with binocular age-related cataract were divided into a conventional group and a monovision group, and there were 21 patients (42 eyes) in each group. Routine cataract phacoemulsification and foldable intraocular lens implantation were performed on all the eyes. Preoperative best-corrected visual acuity and postoperative (one week after the operation) monocular uncorrected distance visual acuity, monocular uncorrected near vision acuity, binocular uncorrected distance visual acuity, binocular uncorrected near vision acuity were compared for the two groups. Data were analyzed by the SAS 8.2 statistics program. Results ① The mean preoperative best-corrected visual acuity was 4.44 of the conventional group compared with 4.47 of the monocular visual group (P>0.05), and there was no statistically significant difference. ②Statistically significant difference of postoperative monocular uncorrected distance visual acuity was not found between the conventional group (4.90) and the dominant eyes in the monocular visual group (4.94, P >0.05), however, was found when compared with the non-dominant eyes in the monocular visual group (4.71, P 0.05), but was found when compared with the non-dominant eyes in the monocular visual group (4.78, P 0.05), however, there was statistically significant difference of postoperative binocular uncorrected near visual acuity between the conventional group (4.42) and the monocular visual group (4.78, P <0.05). Conclusions The postoperative binocular uncorrected distance visual acuity of the monovision pseudophakic eyes is the same as the conventional pseudophakic eyes, the near visual acuity is much better than the conventional pseudophakic eyes. The monovision principle to choose the intraocular lens can be better applied in the clinic. Key words: Phacoemulsification; Monovision; Visual performance

User-centered design questions in gaze interfaces have been explored in multitude empirical investigations. Interestingly, the question of what eye should be the input device has never been studied. We compared tracking accuracy between the “cyclopean” (i.e., midpoint between eyes) dominant and non-dominant eye. In two experiments, participants performed tracking tasks. In Experiment 1, participants did not use a crosshair. Results showed that mean distance from target was smaller with cyclopean than with dominant or non-dominant eyes. In Experiment 2, participants controlled a crosshair with their cyclopean, dominant and non-dominant eye intermittently and had to align the crosshair with the target. Overall tracking accuracy was highest with cyclopean eye, yet similar between cyclopean and dominant eye in the second half of the experiment. From a theoretical viewpoint, our findings correspond with the cyclopean eye theory of egocentric direction and provide indication for eye dominance, in accordance with the hemispheric laterality approach. From a practical viewpoint, we show that what eye to use as input should be a design consideration in gaze interfaces.

We questioned 104 consecutive eye casualty patients about any visual disturbance experienced while wearing an eye patch as part of their treatment. Many (31%) reported momentary loss of vision in the uncovered eye. Some experienced this while driving. It was more common (p < 0.0008) if the 'dominant eye' had been patched (47%) rather than the 'non-dominant eye' (16%). In a separate experiment, a number of co-operative subjects were provided with a translucent-coloured occluder to be worn over each eye in turn. They reported a recurring coloured interference in the uncovered eye sparing the monocular crescent. We propose that the loss of vision in the unpatched eye is due to binocular rivalry suppression by the patched eye. This visual disturbance may be a cause of anxiety or risk for the patient. Patched patients should be warned this may occur, and advised to avoid driving or operating machinery.

Purpose To describe the refractive profile of surgical patients with intermittent exotropia (IXT) residing in southern China. Methods Medical records of patients who received strabismus surgery between June 2014 and August 2020 were retrospectively reviewed. Clinical data, including age, sex, refractive errors, preoperative angle of deviation, types of exotropia, accommodative convergence to accommodation ratio (AC/A ratio) and stereopsis, were investigated. Results A total of 2250 patients were included, and 93.6% of patients were younger than 30 years of age. The mean angle of exodeviation was 37.0 ± 14.7 prism degree (PD) and 37.5 ± 15.8 PD at distance and near, respectively. Mean spherical equivalent refraction (SER) values were -0.7 ± 2.4 D and −0.8 ± 2.5 D in the dominant eye and nondominant eye, respectively. Significant differences in SER were observed between the dominant eye and nondominant eye among children at 6 years old or younger. The percentage of myopia increased from 11.0% in children (≤6 years old) to 77.9% in teenagers (13-18 years of age). Significant positive associations between the magnitude of exodeviation and the magnitude of myopia were observed (p < 0.0001). Patients with convergence insufficiency type IXT (p < 0.0001) or AC/A < 2 (p < 0.05) showed a greater magnitude of myopia. The mild hyperopia group included a larger proportion of subjects showing a certain degree of stereopsis (p < 0.05). Conclusions Myopia was present in more than half of our patients (51.2%), which is much higher than the percentage in the general population of southern China. Patients with convergence insufficiency, an AC/A ratio < 2, or a larger angle of deviation tended to have a greater magnitude of myopia.