Bivariate Contour Ellipse Area Research Articles

In-Depth Retinal Sensitivity Assessment With the MP3 Type S Microperimeter: A Methods Study.

Retinal sensitivity is frequently listed as an end point in clinical trials, often with long working practices. The purpose of this methods study was to provide a new workflow and reduced test time for in-depth characterization of retinal sensitivity. A workflow for the MP3-S microperimeter with detailed functional characterization of the retina under photopic, mesopic, and scotopic conditions was evaluated. Grids of 32 and 28 test positions for photopic/mesopic and scotopic, respectively, were tested in 12 healthy individuals and compared with an established 68-point grid for test time, mean sensitivity (MS), and bivariate contour ellipse area (BCEA). The mean test time (range; ±SD) was 10.5 minutes (8.4-14.9; ±2.0) in the 68-point grid and 4.3 minutes (3.8-5.0; ±0.4) in the 32-point grid, which was significantly different (P < 0.0001). The mean of difference in test time (±SD; 95% confidence interval) was 6.1 minutes (±2.0; 4.6-7.6). MS and BCEA were significantly correlated between grids (r = 0.89 and 0.74; P = 0.0005 and 0.014, respectively). Mean test time of subjects who underwent the full protocol (n = 4) was 2.15 hours. The protocol suggested herein appears highly feasible with in-depth characterization of retinal function under different testing conditions and in a short test time. The protocol described herein allows for characterization of the retina under different testing conditions and in a short test time, which is relevant due to its potential for patient prognostication and follow-up in clinical settings and also given its increasing role as a clinical trial end point.

Evaluation of the macular sensitivity and retinal ganglion cell layer in unilateral amblyopia.

To assess macular sensitivity and fixation pattern obtained by microperimetry and ganglion cell complex (GCC) obtained by optical coherence tomography (OCT) in cases with unilateral amblyopia and to compare with control. The study was conducted with 30 patients with amblyopia, aged 5-18 years, and 30 control eyes of healthy children in the same age group. Participants underwent full ophthalmological examination. Macular sensitivity, stabilization, and location of fixation values were measured using microperimetry. The GCC values were obtained by OCT. Measurements were compared between amblyopic eyes, fellow eyes, and controls. Any correlation between GCC, macular sensitivity, and fixation was investigated. P < 0.05 was considered statistically significant. The mean age was 10.13 ± 3.49 years in the amblyopia group and 11.53 ± 2.7 years in the control group. Three groups were formed: amblyopic eyes (Group 1, n = 30), fellow eyes (Group 2, n = 30), and control eyes (Group 3, n = 30). The macular sensitivity values were found highest in the control group (P = 0.007). Bivariate contour ellipse area 1, which is the numerical value of fixation stabilization, was measured to be the lowest in the control group (P < 0.0001). In the analysis among the three groups, no significant difference was observed in terms of the GCC (P = 0.229). In the correlation analyses, a significant correlation was detected between macular sensitivity and GCC values in amblyopic eyes. In amblyopic eyes, the macular sensitivity was significantly lower and the GCC thickness was found to be in a positive correlation with macular sensitivity.

Does the sampling frequency of an eye tracker affect the detection of glaucomatous visual field loss?

Evidence suggests that eye movements have potential as a tool for detecting glaucomatous visual field defects. This study evaluated the influence of sampling frequency on eye movement parameters in detecting glaucomatous visual field defects during a free-viewing task. We investigated eye movements in two sets of experiments: (a) young adults with and without simulated visual field defects and (b) glaucoma patients and age-matched controls. In Experiment 1, we recruited 30 healthy volunteers. Among these, 10 performed the task with a gaze-contingent superior arcuate (SARC) scotoma, 10 performed the task with a gaze-contingent biarcuate (BARC) scotoma and 10 performed the task without a simulated scotoma (NoSim). The experimental task involved participants freely exploring 100 images, each for 4 s. Eye movements were recorded using the LiveTrack Lightning eye-tracker (500 Hz). In Experiment 2, we recruited 20 glaucoma patients and 16 age-matched controls. All participants underwent similar experimental tasks as in Experiment 1, except only 37 images were shown for exploration. To analyse the effect of sampling frequency, data were downsampled to 250, 120 and 60 Hz. Eye movement parameters, such as the number of fixations, fixation duration, saccadic amplitude and bivariate contour ellipse area (BCEA), were computed across various sampling frequencies. Two-way ANOVA revealed no significant effects of sampling frequency on fixation duration (simulation, p = 0.37; glaucoma patients, p = 0.95) and BCEA (simulation, p = 0.84; glaucoma patients: p = 0.91). BCEA showed good distinguishability in differentiating groups across different sampling frequencies, whereas fixation duration failed to distinguish between glaucoma patients and controls. Number of fixations and saccade amplitude showed variations with sampling frequency in both simulations and glaucoma patients. In both simulations and glaucoma patients, BCEA consistently differentiated them from controls across various sampling frequencies.

Retinal Artery Angles in High Axial Myopia and Its Relationship With Visual Function.

To evaluate the retinal artery angles in high axial myopia and assess the correlation with other morphometric and functional parameters. This cross-sectional study included 112 eyes of 112 patients with high axial myopia. Based on axial length (AL), the participants were divided into three groups: group 1 (26 ≤ AL < 28 mm), group 2 (28 ≤ AL < 31 mm), and group 3 (≥31 mm). Scanning laser ophthalmoscopy imaging was used to analyze the retinal artery angle (Yugami correlated angle [YCA]). Retinal vascular densities (VDs) in both superficial capillary plexuses (SCPs) and deep capillary plexuses were evaluated. Fixation behavior, including retinal mean sensitivity (MS), macular fovea 2°, 4° fixation rate (P1, P2), and 68.2% bivariate contour ellipse area, were analyzed by microperimetry. Finally, the correlation between YCAs and AL, VDs, best-corrected visual acuity (BCVA), and fixation behavior was assessed. The YCAs showed significant differences among the three groups (all P < 0.001, respectively). Compared to group 1, the YCA decreased in group 2 (P < 0.001) and continued to decrease in group 3 (P = 0.043). The correlation analysis revealed that smaller YCAs (YCA, YCA1/2, YCA1/4) were positively correlated with the longer AL (ρ = 0.580, 0.545, 0.448, P < 0.001) and lower VDs in any sector in SCPs (all P ≤ 0.05). Furthermore, smaller YCAs were positively correlated with decreased BCVA (ρ = 0.392, 0.387, 0.262; all P < 0.001) and reduced MS (ρ= 0.300, 0.269, 0.244; all P < 0.05). Smaller YCAs were correlated with longer AL, lower VD in SCP, decreased BCVA, and reduced MS. The YCAs might reflect vascular deformation caused by axial elongation and could potentially be useful in predicting visual function in high axial myopia. The quantitative analysis of YCAs in fundus photography holds potential clinical value in predicting visual function in high axial myopia.

Biofeedback Training after Successful Inverted Internal Limiting Membrane (ILM)-Flap Technique for High Myopic Macular Hole.

Microperimetric biofeedback training improved visual acuity and fixation stability in patients who previously underwent macular surgery. We aimed to compare the functional results of biofeedback training with the standard of care in patients who underwent successful inverted Internal Limiting Membrane (ILM)-flap technique for high myopic macular holes (hMMH). This was a retrospective, comparative, cohort study. Patients with hMMH after surgical hole closure underwent microperimetric biofeedback using structured light stimulus plus acoustic tone (n = 12; Biofeedback) or standard of care with scheduled visits (n = 11; Control). Best-corrected visual acuity, retinal sensitivity at central 12° (RS) and 4° (CRS) with a mean deviation at central 12° (MD), and fixation stability as bivariate contour ellipse area (BCEA 68%, 95%, and 99%) were assessed at baseline and month 1, 3, 6, and 12. The Mann-Whitney test was used to test the difference between the groups. Baseline functional parameters were not significantly different among the groups. BCVA significantly improved in each group (Biofeedback, p = 0.002; Control, p ≤ 0.02) at all follow-up visits. CRS significantly improved at 6 (p = 0.03) and 12 (p = 0.01) months in the Biofeedback group and at month 12 (p = 0.01) in the Control group. RS (p = 0.001) and MD (p = 0.005) improved at the last follow-up only in the trained group. After training, BCEA 68% and 95% significantly improved (6 and 12 months, p < 0.05). The Biofeedback group had better results in RS (p ≤ 0.02), CRS (p ≤ 0.02), and BCEA 68%, 95%, and 99% (p ≤ 0.01) compared to the Control at all follow-ups. BCVA and MD were better in the Biofeedback group at month 3 (p = 0.01), and month 3 (p = 0.01) and 12 (p = 0.003), respectively. Microperimetric biofeedback can increase retinal sensitivity and stabilize fixation better than the standard care over months after a successful inverted ILM-flap for hMMH.

Eye movements in patients with post-COVID condition.

Eye movement control is impaired in some neurological conditions, but the impact of COVID-19 on eye movements remains unknown. This study aims to investigate differences in oculomotor function and pupil response in individuals who suffer post-COVID-19 condition (PCC) with cognitive deficits. Saccades, smooth pursuit, fixation, vergence and pupillary response were recorded using an eye tracker. Eye movements and pupil response parameters were computed. Data from 16 controls, 38 COVID mild (home recovery) and 19 COVID severe (hospital admission) participants were analyzed. Saccadic latencies were shorter in controls (183 ± 54 ms) than in COVID mild (236 ± 83 ms) and COVID severe (227 ± 42 ms) participants (p = 0.017). Fixation stability was poorer in COVID mild participants (Bivariate Contour Ellipse Area of 0.80 ± 1.61°2 vs 0.36 ± 0.65 °2 for controls, p = 0.019), while percentage of pupil area reduction/enlargement was reduced in COVID severe participants (39.7 ± 12.7%/31.6 ± 12.7% compared to 51.7 ± 22.0%/49.1 ± 20.7% in controls, p < 0.015). The characteristics of oculomotor alterations found in PCC may be useful to understand different pathophysiologic mechanisms.

The Relationship between Fixation Stability and Retinal Structural Parameters in Children with Anisometropic, Strabismic and Mixed Amblyopia.

(1) Background: Amblyopia is an ocular condition leading to structural and functional changes. The relationship between these changes is complex and remains poorly understood. (2) Methods: Participants included 31 children aged 5 to 9 years with strabismic (n = 9), anisometropic (n = 16) and mixed (n = 6) unilateral amblyopia, and 14 age-matched non-amblyopic children. The 95% and 63% Bivariate Contour Ellipse Area (BCEA), axial length, Foveal Avascular Zone (FAZ) area, center macular thickness and volume were assessed. The relationship between these parameters was explored. (3) Results: Statistically significant differences were found among the four groups in best corrected distance visual acuity (BCVA) (p < 0.001), BCEA 95% (p = 0.002) and BCEA 63% (p = 0.002), but not in the FAZ area, central macular thickness, central macular volume and axial length. Eyes with amblyopia had poorer BCVA and larger fixation instability than controls. Inter-ocular differences were more significant in patients with strabismic amblyopia, particularly in BCVA (p = 0.003), central macular thickness (p < 0.001) and central macular volume (p = 0.002). In amblyopic eyes, BCEA 95% and 63% were correlated with BCVA, but not with the FAZ area. (4) Conclusion: Amblyopia is associated with a reduction in fixation stability and BCVA, although there is a general lack of correlation with structural changes, suggesting a complex interaction between anatomy and function in amblyopia.

Time in range as a useful marker for evaluating retinal functional changes in diabetic retinopathy patients.

To elucidate the relationship between macular sensitivity and time in range (TIR) obtained from continuous glucose monitoring (CGM) measures in diabetic patients with or without diabetic retinopathy (DR). This was a cross-sectional study including 100 eyes of non-DR patients and 60 eyes of DR patients. An advanced microperimetry was used to quantitate the retinal mean sensitivity (MS) and fixation stability in central macula. TIR of 3.9-10.0 mmol/L was evaluated with CGM. Pearson coefficient analysis and multiple linear regression analysis were used to assess the correlation between TIR and retinal sensitivity. In a comparison of non-DR patients, significant differences (P<0.05) were found in HbA1c, TIR, coefficient of variation (CV), standard deviation of blood glucose (SDBG) and mean amplitude of glucose excursion (MAGE) values in DR patients. Besides, those DR patients had significantly poor best-corrected visual acuity (BCVA, logMAR, P=0.001). In terms of microperimetry parameters, retinal mean sensitivity (MS) and the percentages of fixation points located within 2° and 4° diameter circles were significantly decreased in the DR group (P<0.001, P<0.001, P=0.02, respectively). The bivariate contour ellipse area (BCEA) encompassing 68.2%, 95.4%, 99.6% of fixation points were all significantly increased in the DR group (P=0.01, P=0.006, P=0.01, respectively). Correlation analysis showed that MS were significantly correlated with HbA1c (P=0.01). TIR was positively correlated with MS (r=0.23, P=0.01). SDBG was negatively correlated with MS (r=-0.24, P=0.01) but there was no correlation between CV and MAGE with MS (P>0.05). A multivariable linear regression analysis was performed to prove that TIR and SDBG were both independent risk factors for MS reduction in the DR group. TIR is correlated with retinal MS reduction in DR patients, suggesting a useful option for evaluating DR progression.

Microperimetry Reliability Assessed From Fixation Performance.

Microperimetry provides an accurate assessment of central retinal sensitivity due to its fundus-tracking capability, but it has limited reliability indicators. One method currently employed, fixation loss, samples the optic nerve blind spot for positive responses; however, it is unclear if these responses arise from unintentional button presses or from tracking failure leading to stimuli misplacement. We investigated the relationship between blind spot scotoma positive responses (termed scotoma responses) and fixation. Part 1 of the study involved a custom grid of 181 points centered on the optic nerve that was constructed to map physiological blind spots in primary and simulated eccentric fixation positions. Scotoma responses and the 63% and 95% fixation bivariate contour ellipse areas (BCEA63 and BCEA95) were analyzed. In Part 2, fixation data from controls and patients with retinal diseases (234 eyes from 118 patients) were collected. Part 1, a linear mixed model of 32 control participants, demonstrated significant (P < 0.001) correlation between scotoma responses and BCEA95. In Part 2, the upper 95% confidence intervals for BCEA95 were 3.7 deg2 for controls, 27.6 deg2 for choroideremia, 23.1 deg2 for typical rod-cone dystrophies, 21.4 deg2 for Stargardt disease, and 111.3 deg2 for age-related macular degeneration. Incorporating all pathology groups into an overall statistic resulted in an upper limit BCEA95 = 29.6 deg2. Microperimetry reliability is significantly correlated to fixation performance, and BCEA95 provides a surrogate marker for test accuracy. Examinations of healthy individuals and patients with retinal disease are deemed unreliable if BCEA95 > 4 deg2 and BCEA95 > 30 deg2, respectively. Microperimetry reliability should be assessed using fixation performance as summarized by BCEA95 rather than the level of fixation losses.

Evaluation of fixation characteristics in amblyopia using microperimetry.

To evaluate fixation characteristics in amblyopia using macular analyzer integrity assessment (MAIA) microperimetry and to investigate the factors affecting fixation stability. This prospective, cross-sectional study enrolled a total of 58 amblyopic patients who were between 8 and 55years old. Average threshold macular sensitivity (AT) and fixation characteristics were assessed using MAIA microperimetry. Two Bivariate contour ellipse area (BCEA) fixation indices (63% and 95% proportional values) and the percentage of fixation points within 1° and 2° from the fovea (P1 and P2) were used to assess fixation stability. Non-amblyopic fellow eyes were used as the control group for comparison. AT and fixation stability indices (P1, P2, BCEA 63%, BCEA 95%) were worse in the amblyopic eyes than in the fellow eyes (p < 0.05, for all indices). There was a moderate positive correlation between best corrected visual acuity (BCVA), and AT, and P2, and a moderate negative correlation between BCVA, and BCEA indices. 48% of the eyes were eccentrically fixating (the percentage was 25% in the anisometropic group, 52% in the strabismic group, and 69% in the combined group) and 32% in the non-amblyopic eye (p = 0.052). The preferred fixation eccentricity in amblyopic eyes was significantly greater than the non-amblyopic eyes (p = 0.004), and there was a negative correlation between preferred fixation eccentricity and BCVA (p = 0.012, r = -0.327). Our data showed a decrease in fixation stability, a positive correlation between fixation stability and BCVA, and a negative correlation between preferred fixation eccentricity and BCVA in amblyopic eyes.

Fixation Location and Stability in Best Vitelliform Macular Dystrophy

To analyze fixation location and stability in best vitelliform macular dystrophy (BVMD) and test their association with best-corrected visual acuity (BCVA). Observational, cross-sectional study. Thirty patients (55 eyes) affected by genetically confirmed BVMD were followed up at the Retinal Heredodystrophies Unit of IRCCS San Raffaele Scientific Institute, Milan. Patients underwent testing with macular integrity assessment (MAIA) microperimeter. Fixation location was measured as distance in degrees (°) between preferred retinal locus (PRL) and estimated fovea location (EFL); fixation was defined as eccentric when the distance between PRL and EFL exceeded 2°. Fixation stability was graded as stable, relatively unstable, or unstable and expressed as bivariate contour ellipse area (BCEA, °2). Fixation location and stability. The median distance of the PRL from the anatomic fovea was 0.7°, and fixation location was eccentric in 27% of eyes. Fixation was graded as stable in 64% of eyes, relatively unstable in 13%, and unstable in 24%, with a median 95% BCEA of 6.2°2. The atrophic/fibrotic stage was associated with worse fixation parameters (all P<0.01). Both PRL eccentricity and fixation stability were linearly associated with BCVA: every 1° increase in PRL eccentricity was associated with a 0.07 logarithm of the minimum angle of resolution (logMAR) worse BCVA (P<0.0001) while every 1°2 increase in 95% BCEA was associated with a 0.01 logMAR worse BCVA (P<0.001). No significant intereye correlation was found for PRL eccentricity and fixation stability, as well as no association between the patient's age and fixation parameters. We demonstrated that most eyes affected by BVMD retain a central stable fixation and provided evidence that both fixation eccentricity and stability are strongly associated with visual acuity in BVMD. These parameters may serve as secondary end points for future clinical trials. Proprietary or commercial disclosure may be found after the references.

Effectiveness of visual and acoustic biofeedback eccentric viewing training in conjunction with home exercises on visual function: a retrospective observational review

ABSTRACT The aim of this study is to evaluate the effectiveness of an eccentric viewing training program that combines biofeedback training using micro-perimetry with home exercises on multiple visual function parameters and to explore potential relationships between post-treatment visual function parameters. A retrospective observational review of 27 participants who underwent the training program was performed. Eligible participants were diagnosed with bilateral central scotomas secondary to age-related macular degeneration. All participants undertook up to 15 visual and acoustic biofeedback training sessions and were required to partake in traditional home exercises between sessions. The biofeedback training was conducted in the better eye using the Macular Integrity Assessment microperimeter (MAIA). Distance and near acuity, contrast sensitivity and fixation stability quantified by the P1 and P2 values and the 63% and 95% bivariate contour ellipse area (BCEA) before and after the rehabilitation program were recorded. Significant improvement was noted post-training for distance visual acuity (t(26) = 4938 p = .000), near visual acuity (Z = −4.461 p = .000), contrast sensitivity (Z = −3.647 p = .000) and fixation stability for all measures, including P1 (t(26) = −9.490 p = .000), P2 (t(26) = −7.338 p = 0.000), 63% BCEA (Z = 3.569 p = .000) and 95% BCEA (t(26) = 4.687 p = .000). Significant medium-to-large correlations were also found between most visual function variables. Visual and acoustic biofeedback in conjunction with home exercises has the potential to improve visual function parameters in patients with age-related macular degeneration and irreversible central vision loss.

Gaze instability after exposure to moving visual stimuli in patients with persistent postural-perceptual dizziness.

Persistent postural-perceptual dizziness (PPPD) is a chronic vestibular syndrome lasting more than 3 months. The core vestibular symptoms are dizziness, unsteadiness, and non-spinning vertigo, which are exacerbated by upright posture or walking, active or passive motion, and exposure to moving or complex visual stimuli. Among these, visual exacerbation is a key feature of PPPD for which the neural mechanisms are unknown. We hypothesized that vestibular symptoms may be exacerbated by visual stimuli through gaze behavioral change after exposure to moving or complex visual stimuli. The study aimed to examine gaze stability after exposure to moving visual stimuli in patients with PPPD. Fourteen healthy controls (HCs), 27 patients with PPPD, and 12 patients with unilateral vestibular hypofunction (UVH), showing chronic vestibular symptoms for >3 months, were enrolled in the study. The participants were instructed to fixate on the gazing point at the center of a screen for 30 s before and after 90 s of exposure to moving visual stimuli. Gaze stability, best represented by the bivariate contour ellipse area (BCEA), was compared among three groups, both before and after exposure to the moving visual stimuli. Comparisons between pre- and post-moving visual stimuli in BCEA were also conducted. Correlation between the post/pre ratio of BCEA and vestibular tests, several clinical symptom scales including the Dizziness Handicap Inventory, Niigata PPPD Questionnaire, and Hospital Anxiety and Depression Scale, and the exacerbation of dizziness by exposure to moving visual stimuli was examined in the PPPD group. BCEA, both before and after exposure to moving visual stimuli in the PPPD group, was not different from that in HC and UVH groups. In the PPPD group, BCEA increased significantly after exposure to moving visual stimuli. The post/pre ratio of BCEA correlated with the occurrence of exacerbation of the dizziness sensation by exposure to moving visual stimuli; however, it did not correlate with vestibular tests or clinical symptom scales. Patients with PPPD were more likely to exhibit gaze instability after exposure to moving visual stimuli, which potentially exacerbated vestibular symptoms. This phenomenon may help elucidate the neural mechanisms of visual exacerbation in patients with PPPD.

Analysis of Characteristic Eye Movement Behaviors of Young Adults with Different Degrees of Myopia

To measure the parameters of eye movement of young adult patients of myopia, to compare the differences in the parameters of patient groups with varied degrees of myopia, and to analyze the correlation between eye movement parameters and axial length (AL) and spherical equivalent refraction (SER). A total of 91 young adult patients of myopia were recruited. The subjects were divided into three groups of low, moderate, and high myopia according to their SER. Information on the subjects' age and sex was collected and general clinical examination was completed. The subjects' binocular fixation, reflexive saccade, and antisaccade were measured with eye tracker. One-way ANOVA or Kruskal-wallis test was used to compare the general data and eye movement parameters of the three groups of myopic patients. Pearson or Spearman correlation analysis was used to analyze AL and SER's correlation with 95% bivariate contour ellipse area (BCEA) and saccadic parameters. The 95% BCEA for mild, moderate, and high myopia groups were 2.08 (0.54, 14.69) deg 2, 4.99 (0.94, 49.22) deg 2, and 5.79 (2.18, 64.91) deg 2, respectively. There was significant difference between the 95% BCEA of the three groups ( P=0.029). The 95% BCEA of the mild myopia group was significantly smaller than that of the high myopia group ( P=0.01). There were no significant differences in saccadic parameters among the three groups ( P>0.05). There was a significant positive correlation between 95% BCEA and AL ( r=0.342, P=0.001). There was a significant negative correlation between 95% BCEA and SER ( r=-0.322, P=0.002). There was no significant correlation between the parameters of saccadic movement and the AL or SER ( P>0.05). For young adult myopic patients, the longer the AL is, the higher the degree of the myopia and the worse the fixation stability becomes. The fixation stability of patients with high myopia was significantly worse than that of patients with mild myopia. There was no significant difference in saccadic parameters in patients with different degrees of myopia.

Measurement of Fixational Eye Movements With the Head-Mounted Perimeter Imo.

PurposeAlthough visual field testing is conducted with the subject gazing at a fixation target, constant minute eye movements, called fixational eye movements, do occur during fixation. We examined dynamic changes in fixational eye movements associated with stimulus presentation during visual field testing.MethodsWe used the head-mounted perimeter imo, which is capable of measurement under binocular conditions, with the frame rate of its fixation monitoring camera improved to 300 Hz, to assess fixational eye movements in 18 healthy individuals. We measured changes in fixational eye movements during testing under monocular and binocular conditions and analyzed these changes based on the bivariate contour ellipse area (BCEA). We also assessed the changes in the horizontal and vertical microsaccade rates separately.ResultsBoth the BCEA and horizontal microsaccade rates were higher at 400 to 600 msec after stimulus presentation than during stimulus presentation (P < 0.01). Additionally, the BCEA and vertical microsaccade rates were significantly lower in the binocular condition than in the monocular condition (P < 0.01 and P < 0.05, respectively). We did not observe a significant correlation between the test locations and microsaccade direction during visual field testing.ConclusionsFixational eye movements, especially vertical microsaccade rates, were lower in the binocular condition than in the monocular condition. Visual field testing under binocular conditions is a useful method for suppressing fixational eye movements and stabilizing the fixation during testing and may improve the reliability of the test results.Translational RelevanceVisual field testing under binocular conditions can make the fixation more stable during the testing compared with monocular conditions.

A-01 Changes in Fixational Eye Movements (FEMs) Following Concussion

Abstract Purpose: Identify changes in fixational eye movement (FEMs) outcomes following concussion and assess the association of FEMs outcomes with clinical outcomes including symptoms, neurocognitive, and vestibular/ocular motor. Methods: Participants included thirty-three individuals (13–27 years old; 54.5% female) diagnosed with concussion within the past 21 days. Concussion diagnosis was determined using current consensus guidelines. A tracking scanning laser ophthalmoscope (TSLO) was used to measure FEMS. Participants completed ImPACT, PCSS, and VOMS. Within-subjects changes in FEMS outcomes were calculated using paired-samples t-tests. A backwards stepwise linear regression to predict days to clearance was utilized with all FEMS outcomes as predictors. Results: MeanDriftH (slope of cumulative drift regression calculated horizontally; mean difference = 0.04; p = 0.03; Cohen’s d = 0.43) and drift proportion significantly changed over time (mean difference = 0.03; p = 0.03, d = 0.44). Average peak velocity of microsaccade (MsPkVel) predicted days to recovery (R = 0.26; p = 0.045; n = 24). MsPkVel and average duration of blink correlated with select reports of nausea on VOMS. Microsaccade frequency (r = −0.36; p = 0.04) correlated with NPC fogginess. Drift amplitude (DriftAmp) correlated with NPC distance (r = −0.41; p = 0.02) and VMS headache (r = 0.35; p = 0.04). MeanDriftH was negatively correlated with verbal memory (r = −0.44; p = 0.01), whereas DriftAmp was positively correlated (r = 0.50; p = 0.003). Bivariate contour ellipse area was correlated (r = 0.43; p = 0.01) with slower reaction time on ImPACT. Conclusions: FEMs outcomes demonstrated significant change and were useful in predicting recovery time following concussion. FEMs measurements may provide brief, objective data to augment current clinical assessment and inform prognosis for recovery. Future researchers should examine FEMS outcomes from pre- to post-concussion and explore age and sex differences.

Comparison of image-based quantification methods in evaluating fixation stability using a remote eye tracker in abnormal phoria.

ObjectiveThis study was performed to establish a quantitative evaluation and comparison of fixation stability, as measured by an eye tracker, using image-based areas determined by the bivariate contour ellipse area (BCEA), kernel density estimation (KDE), and Scanpath methods.MethodsThis prospective cross-sectional study included 45 and 20 participants with abnormal and normal phoria, respectively. Eye movements were recorded using a remote eye tracker and were plotted using RStudio software. Image-based areas were evaluated using ImageJ software.ResultsThe image-based areas used to evaluate fixation stability exhibited decreasing stability in the abnormal phoria group in the following order: KDE with ±1 standard deviation (SD), BCEA with ±1 SD, KDE with ±2 SD or Scanpath, and BCEA with ±2 SD. The BCEA tended to be overestimated, and the KDE tended to be underestimated at high density. The Scanpath method had a very high probability area because the area spans all gaze points.ConclusionsFixation stability could be quantified as image-based areas by the KDE, BCEA, and Scanpath methods. Our findings suggest that fixation stability may be evaluated using one or more methods.

CHANGES OF FIXATION STABILITY AND LOCATION AFTER EPIRETINAL MEMBRANE SURGERY.

This study aimed to evaluate fixation stability and position changes after epiretinal membrane (ERM) surgery. This is a retrospective study that included 60 consecutive eyes with idiopathic ERM. All patients received comprehensive ophthalmic examinations preoperatively and 1, 4, and 10 months postoperatively. Main outcome measures included fixation stability and position, bivariate contour ellipse area, and preferred retinal locus. The number of patients with stable fixation and predominantly central fixation was increased significantly after ERM surgery (61.7 vs. 73.3%, P = 0.001; 41.7 vs. 71.7%, P = 0.037). The correlation analysis showed that the preoperative factors associated with improved postoperative fixation stability were a larger bivariate contour ellipse area value (P < 0.001), poorer visual acuity (P = 0.002), advanced stage (P = 0.002), thicker central fovea thickness (P = 0.015), and a longer preferred retinal locus-fovea distance (P = 0.025). As for the improved fixation location, the associated preoperative factors were age (P = 0.003), central fovea thickness (P = 0.044), and preferred retinal locus-fovea distance (P < 0.001). Our observations point to the changes of fixation parameters in patients after ERM surgery. We found that patients with preoperative unstable, eccentric fixation and poor BCVA can significantly benefit from the surgery. This result indicates that even in patients with severe macular damage, the ERM surgery still has great benefits in recovering visual function.

Efficacy of MP-3 microperimeter biofeedback fixation training for low vision rehabilitation in patients with maculopathy

BackgroundTo evaluate the efficacy of MP-3 microperimeter biofeedback fixation training (MBFT) in vision rehabilitation of low-vision patients affected by macular disease with central vision loss.MethodsSeventeen eyes (7 age-related macular degeneration, 10 myopic maculopathy) of 17 patients were included in this prospective, interventional study. The preferred retinal locus was determined by comprehensive ophthalmoscopic fundus evaluation including fundus photography, autofluorescence, optical coherence tomography, and microperimetry. The rehabilitation consisted of three 10-min sessions per eye to be performed twice per week for 20 consecutive weeks using the MP-3 microperimeter. Best corrected visual acuity (BCVA), reading speed, mean central sensitivity, the percentages of fixation points within specified regions, bivariate contour ellipse area (BCEA) and the 25-item National Eye Institute visual function questionnaire (NEI-VFQ-25) were recorded pre- and post-training.ResultsThe final BCVA, reading speed and mean central sensitivity all showed significant improvements after rehabilitation (P < 0.0001, P = 0.0013, and P = 0.0002, respectively). The percentages of fixation points located within 2° and 4° diameter circles both significantly increased after training (P = 0.0008 and P = 0.0007, respectively). The BCEA encompassing 68.2, 95.4, 99.6% of fixation points were all significantly decreased after training (P = 0.0038, P = 0.0022, and P = 0.0021, respectively). The NEI-VFQ-25 scores were significantly increased at the end of the rehabilitation training (P < 0.0001).ConclusionRehabilitation with MP-3 MBFT is a user-friendly therapeutic option for improving visual function, fixation stability, and quality of life in advanced macular disease.Trial registrationThe prospective study was registered with the Chinese Clinical Trial Registry (http://www.chictr.org.cn/). Trial Registration Number: ChiCTR2000029586. Date of registration: 05/02/2020.

Alterations in Fixation Indices in Primary Open-Angle Glaucoma by Microperimetry.

The aim of this study was to determine whether primary open-angle glaucoma (POAG) is associated with changes in fixation stability parameters assessed by microperimetry (MP) and whether the severity of glaucoma is related to a deterioration in these indicators. This study analyzed fixation stability using MP macular analyzer integrity assessment (MAIA) in patients with mild and moderate/severe POAG and healthy controls. The resulting fixation indices were correlated with parameters used to assess retinal function with MP and standard automated perimetry (SAP) and retinal structure with optical coherence tomography (OCT) and OCT angiography (OCTA). We enrolled 54 eyes in the POAG groups (32 eyes with mild POAG and 22 eyes with moderate/severe POAG) and 24 eyes in the healthy group. It was shown that fixation stability in POAG eyes deteriorated with increasing disease severity, and significant differences in bivariate contour ellipse area (BCEA) including 95% of fixation points were observed among groups (p = 0.042). Quantitative analysis of structural and functional retinal parameters also showed significant deterioration with the progression of glaucoma (p < 0.001). Correlations among fixation parameters and abnormalities in the retinal structure and function were confirmed. We concluded that POAG is associated with disturbances in the fixation pattern, which worsen as the disease progresses and can be effectively assessed by performing a MP test.