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Purpose: No method to quantitatively evaluate stereopsis within the 15º visual field has been clinically established. We developed a program to measure paracentral stereopsis and evaluated its feasibility in visually normal participants. Study design: Experimental investigation Methods: Ten visually normal volunteers with stereopsis of 60 arcseconds or better were included. The Stereo Eccentricity Analysis (SEA) program for stereopsis measurement across the visual field was integrated into the binocular visual field analyzer imovifa®. Subjects with established binocular stereopsis detected a stereoscopic circular target presented with crossed disparity on random dots at the fovea, 3°, 5°, 10°, and 15° on the 45°, 135°, 225°, and 315° meridians. The subjects performed two tasks for measurement in the periphery: a detection task by pressing the response button when the circular target was perceived and a localization task by tilting a joystick to indicate in which quadrant the circular target was perceived. The duration of the target presentation was 500 ms. Results: The stereo thresholds at 0º and 3° did not significantly differ. The thresholds at 10º and 15º were significantly higher than at 0° (P < 0.01). While no inter-individual threshold difference was observed at the fovea, the difference was large at 15°. The stereo thresholds for the detection and localization tasks also did not differ significantly. Conclusion: With the SEA program, paracentral stereopsis can be measured and the stereo threshold increases with eccentricity. The SEA program appears to be a feasible clinical method to evaluate paracentral stereopsis. [ABSTRACT FROM AUTHOR]

Background: Digoxin related retinal toxicity causes blurred vision, photophobia, central scotoma, color vision abnormality, and electroretinography (ERG) abnormalities. Here, we report a case with transient abnormalities in vison, in which fundus autofluorescence (FAF), optical coherence tomography (OCT), and ERG findings resembled those in KCNV2 (potassium voltage-gated channel modifier subfamily V member 2)-associated retinopathy. Case report: An 89-year-old woman presented with complaints of acute blurred vision, nyctalopia, photophobia, and color vision abnormality. She received digoxin for tachycardia induced by atrial fibrillation for a month. The fundi showed a faint white ring at the fovea, which showed hyperfluorescence in FAF. OCT showed a thickened EZ in the macula. A dark-adapted (DA)-30 ERG showed a reduced and "squaring (trough-flattened)" a-wave, and a delayed, supernormal b-wave, resulting in a high b/a-wave amplitude ratio. The digoxin dose was reduced following an elevation in serum levels. Five weeks later, her visual acuities improved, and abnormal hyperfluorescence on FAF disappeared. After 6 months, no visual symptoms were reported. The ellipsoid-zone thickening in OCT improved; however, the b/a-wave amplitude ratio on DA-30 ERG remained high. The b-wave in LA-long-flash ERG was initially reduced, which improved after correction of serum level of digoxin. Conclusions: The patient's clinical findings resembled those of patients with KCNV2-associated retinopathy or temporal hyperkalemia. These disorders appear to have a common pathogenesis, which may be related to abnormal extracellular potassium levels in the retina. The on-bipolar cells seemed to be more affected than the off-bipolar cells in digoxin related retinal toxicity. [ABSTRACT FROM AUTHOR]

Visual field (VF) test is one of the most vital tests in the diagnosis of glaucoma and to monitor the disease worsening. In the past couple of decades, the standard automated perimetry (SAP) test takes a major role in VF test for glaucoma patients. The SAP has been demanded to finish a test in short time without sacrificing accuracy. In this study, we developed and evaluated the performance of a new perimetric algorithm (ambient interactive zippy estimation by sequential testing (ZEST): AIZE) by computer simulation. AIZE is a modification of the ZEST procedure that utilizes the spatial information (weighted likelihood: WL) of neighboring test locations, which varies from the distance to the tested location, to estimate a visual threshold. Ten glaucomatous and 10 normal empirical visual field (VF) test results were simulated with five error conditions [(3% false positives (FP), 3% false negatives (FN)), (9% FP, 9% FN), (15% FP, 15% FN), (3% FP, 15% FN), (15% FP, 3% FN)]. The total number of test presentations and the root mean square error (RMSE) of the estimated visual sensitivities were compared among AIZE, the non-weighted test (WL = 0) and the fixed-weighted test (WL = 0.33). In both glaucomatous (G) and normal (N) VFs, the fixed-weighted test had the lowest number of test presentations (median G 256, N 139), followed by the AIZE (G 285, N 174) and the non-weighted test (G 303, N 195). The RMSE of the fixed-weighted test was lower (median 1.7 dB) than that of the AIZE (1.9 dB) and the non-weighted test (1.9 dB) for normal VFs, whereas the AIZE had a lower RMSE (3.2 dB) than the fixed-weighted test (4.5 dB) and the non-weighted test (4.0 dB) for glaucomatous VFs. Simulation results showed that AIZE had fewer test presentations than the non-weighted test strategy without affecting the accuracy for glaucomatous VFs. The AIZE is a useful time saving test algorithm in clinical settings. [ABSTRACT FROM AUTHOR]

Purpose: Kinetic programs in four automated perimeters were evaluated and compared for their clinical usefulness using four simulated visual field (VF) patterns. Methods: Using the results of conventional Goldmann manual kinetic perimetry (MKP), simulated fields with concentric contraction, a temporal residual island only, a small central island with a temporal island, and a ring scotoma were created. Four kinetic programs, Humphrey 750i Kinetic Test (Humphrey), OCULUS Twinfield 2 Kinetic Perimetry (OCULUS), OCTOPUS 900 Goldmann Kinetic Perimetry (OCTOPUS GKP), and Kowa AP-7000 Isopter (Kowa) were tested by the 4 simulated defect patterns using stimuli of V/4e, I/4e, I/3e, I/2e, and I/1e at speeds of 3 and 5°/s. Results: Except Humphrey, OCULUS, OCTOPUS GKP, and Kowa could obtain isopters nearly comparable to those of Goldmann MKP. However, their results were considerably influenced by the examiner's skill. Besides, Humphrey had restrictions on target presentation, and OCULUS and Kowa had problems in isopter drawing and in filling in the scotoma. OCTOPUS GKP was the only method that could correctly detect and depict all four defect patterns. It also had relatively shorter test durations among the three methods excluding Humphrey, which did not have a built-in function for test duration measurement. The perimeters' test ranges for the periphery were 90° for Humphrey, OCULUS, and OCTOPUS GKP, and 80° for Kowa. Conclusion: To assess kinetic fields with various defect patterns, OCTOPUS GKP seems to be the most useful method. [ABSTRACT FROM AUTHOR]

To report the light- and dark-adapted perimetric findings in a patient with multiple evanescent white dot syndrome (MEWDS). The patient was a 25-year-old Japanese woman who underwent comprehensive ophthalmological examinations including measurements of the visual acuity, dilated ophthalmoscopy, Goldmann kinetic perimetry, electroretinography (ERG), indocyanine green fundus angiography (ICGA), and optical coherence tomography (OCT). Kinetic perimetry was performed under light- and dark-adapted conditions. The patient was diagnosed with MEWDS by the fundus and visual field findings, and the ICGA abnormalities. Light-adapted perimetry showed an enlargement of the blind spot; however, the size of the blind spot was normalized with dark-adaptation. Amplitude of cone ERG was more reduced than that of rod ERG in the affected eye. The OCT images showed multiple disruptions of the ellipsoid and interdigitation zones. These abnormalities were still present 9 months after the onset although the fundus appeared normal. These findings indicate a persistent cone-dominated dysfunction in a patient with MEWDS. [ABSTRACT FROM AUTHOR]

Purpose: CLOCK CHART is a multi-stimulus-type self-check visual field screening sheet developed by our group. The test chart is rotated during the examination, and the visual field abnormalities are pointed out by the patients themselves. In this study, we evaluated the clinical usefulness of this chart in patients with glaucoma. Methods: We studied 114 eyes of 114 glaucoma patients (average age 60.0 ± 11.1 years) and 45 eyes of 45 normal individuals (average age 45.0 ± 16.4 years) using CLOCK CHART. The static visual fields were obtained using the Octopus 101 G2 program and classified using the Aulhorn classification as modified by Greve (stages 0-I to IV) and by mean defect (MD; early <6 dB; moderate 6 ≤ MD ≤12 dB; severe >12 dB).The sensitivity and specificity of CLOCK CHART for detecting visual field abnormalities were evaluated within the entire 25° field and at the 5°, 10°, 15°, 20°, and 25° eccentricity zones. The visual field agreement between the results of CLOCK CHART and the static visual fields were also evaluated. Results: In glaucomatous eyes, the sensitivity of CLOCK CHART was 85, 93, and 100 % for Greve stages I, II and III-VI, respectively, and 87, 93, and 97 % for the MD value in early, moderate, and severe eyes, respectively. The agreement of the visual field defect area in CLOCK CHART with the static fields was 85 and 100 % with Greve stages 0-I to I and II-VI, respectively, and 91, 96, and 96 % in early, moderate and severe glaucomatous eyes according to MD, respectively. The specificity of CLOCK CHART was 89 %. Conclusion: CLOCK CHART is a simple and reliable self-check screening chart for detecting visual field abnormalities in patients with glaucoma. [ABSTRACT FROM AUTHOR]

Purpose: To assess the results of perimetry recorded under dark- and light-adapted (DA and LA) conditions in patients with acute zonal occult outer retinopathy (AZOOR) and to compare the results of electroretinography (ERG) and spectral-domain optical coherence tomography (SD-OCT) in two groups of AZOOR patients. Methods: Twelve patients with AZOOR were studied. The diagnosis of AZOOR was based on the results of ophthalmoscopy, Goldmann kinetic perimetry, and multifocal ERGs. In addition, DA and LA perimetry, ERG, and SD-OCT were performed. The patients were followed for 1-9 years. Results: The patients were classified into two types: type A patients (3) had a scotoma detected by both DA and LA perimetry, normal or equally abnormal cone and rod ERGs, atrophy of the outer nuclear layer (ONL), and disruption of the inner segment/outer segment (IS/OS) junction line in the OCT images. Type B patients (7) had a scotoma that was more prominent in LA than in DA perimetry and a continuous IS/OS junction line in the OCT images. Two patients had characteristics of both type A and type B AZOOR. Conclusions: Our findings suggest that eyes with type A AZOOR have focal and severe impairment of both the rods and cones, and eyes with type B AZOOR have focal and specific impairment of the cones. [ABSTRACT FROM AUTHOR]

Background: Treatment for intermittent exotropia X(T) aims to keep the eye in a phoric position and to maintain the phoria. However, maintenance of phoria is difficult even after treatment, and the cause is unclear. The aim of this study was to investigate the presence of suppression during tropia and/or phoria in X(T), and to determine how the suppression affected patient's ability to maintain phoria. Methods: Medical records of 89 children with X(T) (mean age, 9.8 ± 2.7 years) were reviewed retrospectively. According to their previous treatment for X(T), the patients were divided into four groups and compared: untreated and under observation only (28 patients), surgical treatment (32 patients), orthoptic training (eight patients) and a combined treatment of surgery and orthoptic training (21 patients). Suppression during phoria was evaluated by a physiologic diplopia test, and suppression during tropia was evaluated by a convergence test or a cover test when fusion broke. Phoria maintenance was achieved if a phoric condition was maintained even when the fusion broke at both near and far. Furthermore, the Bagolini's red filter bar was used to quantitatively assess patient's ability to maintain phoria at near and far distances. Results: No subject only suppressed during phoria. Patients who suppressed under both conditions could not maintain phoria. Suppression under both conditions significantly correlated with phoria maintenance and the ability to maintain phoria ( P < 0.01, Fisher's exact probability test). All the patients with a strong ability to maintain phoria did not suppress under either condition. As compared to the surgical treatment group, the combined treatment group had a higher percentage of patients who did not suppress under either condition and could maintain the phoria. Suppression under both conditions also significantly correlated the treatment methods ( P < 0.01, Chi-square for the independence test). Conclusions: Suppression under both tropic and phoric conditions significantly relates to the outcome of patients' phoria maintenance and their ability to maintain a phoric position. Suppression under both conditions is an important indication of whether X(T) shifts to constant exotropia. [ABSTRACT FROM AUTHOR]

Abstract Background. Visual information projected onto corresponding points on the right and left retinas converges on the binocular cells in the visual cortex. The aim of this study is to investigative the characteristics of the receptive field for binocular stimulation in the central visual field of normal-sighted human subjects. Methods. We investigated the receptive field for binocular stimulation under fusion conditions by combining the Octopus 201 with the space synoptophore. We measured binocular and monocular sensitivities while the fusion patterns were projected onto the Octopus 201 cupola, using the space synoptophore. We designed a new program to test 37 points in the central 6° visual field. Six target sizes were tested: the white-spot targets of 0.054°, 0.108°, 0.216°, 0.431°, 0.862° and 1.724° projected diameters. Results. The threshold energy necessary for binocular stimulation was lower than that for the monocular stimulation in all subjects. This difference was more obvious on the test points that were more distant from the fovea when target sizes of 0.054° and 0.108° were used. The amount of binocular summation ratio was highest for target size 0.054° in each stimulus area in the central 6° of the visual field. When we measured binocular summation using target sizes larger than 0.108°, the result was the constant summation. Conclusions. The size of the receptive field for binocular stimulation is smaller than monocular stimulation under the same fusion condition. The amount of binocular summation varies as a function of target size. [ABSTRACT FROM AUTHOR]