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

Purpose: Although 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. Methods: We 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. Results: Both 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. Conclusions: Fixational 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 Relevance: Visual field testing under binocular conditions can make the fixation more stable during the testing compared with monocular conditions.

Clinical course of a Japanese girl with Leber congenital amaurosis associated with a novel nonsense pathogenic variant in NMNAT1: a case report and mini review.

Leber congenital amaurosis (LCA), although rare, is one of the most severe forms of early-onset inherited retinal dystrophy (IRD). Here, we review the molecular genetics and phenotypic characteristics of patients with NMNAT1-associated IRD. The longitudinal clinical and molecular findings of a Japanese girl diagnosed with LCA associated with pathogenic variants in NMNAT1 c.648delG, (p.Trp216Ter*) and c.709C>T (p.Arg237Cys) have been described to highlight the salient clinical features of NMNAT1-associated IRD.

Utility of CLOCK CHART binocular edition for self-checking the binocular visual field in patients with glaucoma.

BACKGROUND/AIMS: Car accidents caused by drivers unaware of their visual field (VF) defects under binocular vision have become an issue. We developed a simple self-check chart (CLOCK CHART binocular edition (CCBE)) to help patients with glaucoma recognise their abnormalities in the binocular VF and evaluated its usefulness. METHODS: The chart has four targets displayed at 10°, 15°, 20° and 25° eccentricities. The examinee gradually rotates the chart 360° clockwise. At every 30°, the examinee confirms the fixation and indicates if all four targets can be seen. This study enrolled 88 eyes of 44 patients with glaucoma (mean age, 64.4±13.1 years) and 64 eyes of 32 visually normal individuals (mean age, 32.0±8.4 years). Except the CCBE test, static VF testing using the Humphrey field analyser (HFA) Swedish Interactive Threshold Algorithm-Standard 30-2 and binocular Esterman programmes was also performed for the subjects with glaucoma. RESULTS: VF abnormality was defined as two or more contiguous points with a sensitivity of <10 dB within the central 30°. The CCBE test had sensitivities of 85% and 82% with respect to the HFA and Esterman results, respectively. We also used the British VF standards for Group 1 (car/motorcycle) drivers, and a sensitivity of 88% was obtained for the CCBE. The chart had a specificity of 100% for the visually normal subjects. CONCLUSION: The CCBE test enables drivers with glaucoma to notice their VF abnormalities under binocular condition. The application of this simple self-check method appears promising for occasions such as driver licensing.

Distribution and Progression of Visual Field Defects With Binocular Vision in Glaucoma.

PURPOSE: To evaluate the distribution and progression of glaucomatous visual field (VF) defects with binocular vision. PATIENTS AND METHODS: Subjects were 167 patients (average age, 67±10.7 y) with glaucoma who received the Humphrey 24-2 VF test (SITA-Standard) for the 2 eyes. Using the Best Location Algorithm, patient's binocular integrated VF (IVF) was calculated from their Humphrey 24-2 results. Of 167, 77 subjects (average age, 68±11.0 y) also underwent monocular/binocular Humphrey Esterman tests. Patient's stage of glaucomatous VF loss was classified by the Esterman Disability Score for each test, and the distribution and progression of the defects with binocular vision was evaluated for each stage. The frequencies of the defects in the upper and lower halves of the VF were also investigated. RESULTS: With the IVF, the glaucomatous VF defects were most frequently found around the Mariotte blind spots and the Bjerrum areas and extended to the periphery. With the binocular Humphrey Esterman VF, the defects were most frequently found around the bitemporal and Bjerrum areas. The IVF results showed 31%, 49%, and 20% of the patients with the earliest glaucoma having defects in the upper, lower, and both halves of the VF, respectively. CONCLUSIONS: Glaucomatous VF defects with binocular vision were frequently found at the Mariotte blind spots in the central VF and around the bitemporal areas in the periphery. They appeared to have distributions and progression different from those of the defects with monocular vision previously reported.

[Problems of visual field disturbance criteria in visual impairment grade 5].

PURPOSE: In 1995, the Act on Welfare of Physically Disabled Persons was revised and the visual impairment grading methods were modified. In this revision, the target size for peripheral visual field measurements was changed from V/4 to I/4. We compared the area of I/4 and V4 visual fields in normal eyes and evaluated its influence on the decision of the visual impairment grade 5. SUBJECTS AND METHODS: Goldmann kinetic perimetry results obtained from 137 eyes of 137 subjects (age 10-79, average ± SD: 47.0 ± 17.5) at Kinki University Hospital were retrospectively evaluated. The V/4 and I/4 isopter areas were calculated using Image J and compared with the normal visual field range in the visual impairment criteria. RESULTS: The V/4 isopter area decreased from age 70 and the I/4 isopter area decreased significantly from age 50. The aging slope of the isopter areas were significantly larger in I/4 than in V/4. In age 60 to 69, 19% showed a smaller I/4 isopter area than that of the grade 5 criteria. In age 70 to 79, 75% showed a smaller I/4 isopter area than that of the grade 5 criteria. CONCLUSION: In some elderly people, the binocular I/4 isopter area is smaller than the visual impairment grade 5 criteria.