Abstract
Purpose :
The characteristics of fixational eye movements during clinical visual field (VF) tests are not well-known. In this study, we measured fixational eye movements during VF tests using the head-mounted perimeter imo under binocular and monocular viewing conditions.
Methods :
Seven healthy volunteers were enrolled in this study. The frame rate of the CMOS sensor camera in the imo was customized, from 30 frames/s (fps) to 300 fps, for recording eye movements in detail. The VF test conditions were as follows: stimulus intensity, 20 dB; stimulus size, III; stimulus presentation, 200 ms; stimulus interval, 1000 ms; fixation point and 9 stimulus locations were arranged on the 45° median with the interval of 5°. Subjects underwent the VF test three times under each of binocular and monocular conditions. The bivariate contour ellipse area (BCEA) was used to evaluate the area of fixational eye movements. The period of before and after the stimulus duration were divided into 5 time windows as follows: “before 2” (b2), b1, stimulus duration, “after 1” (a1) and a2. Each time window was 200 ms. BCEAs from each time window were compared with the Bonferroni method, and the values under binocular and monocular conditions were also compared with the Mann-Whitney U test.
Results :
In the binocular condition, the average BCEAs of b2, b1, stimulus duration, a1 and a2 were 0.039 (SD=0.042) deg2, 0.038 (SD=0.041) deg2, 0.035 (SD=0.042) deg2, 0.042 (SD=0.054) deg2 and 0.051 (SD=0.068) deg2, respectively. In the monocular condition, the average BCEAs of b2, b1, stimulus duration, a1 and a2 were 0.090 (SD=0.170) deg2, 0.111 (SD=0.240) deg2, 0.080 (SD=0.132) deg2, 0.099 (SD=0.163) deg2 and 0.123 (SD=0.221) deg2, respectively. The BCEA in a2 was significantly larger than that in the stimulus duration (p <0.01). BCEAs from each time window in the binocular condition were significantly smaller than in the monocular condition (p <0.001).
Conclusions :
Fixational eye movements after the stimulus duration were significantly larger than those during the stimulus duration. Furthermore, our results show that the binocular condition may reduce fixational eye movements compared with the monocular condition.
This is a 2020 ARVO Annual Meeting abstract.