Evaluation of stimulus velocity in automated kinetic perimetry in young healthy participants

Abstract

This prospective study aimed to evaluate the stimulus velocity for automated kinetic perimetry based on the test duration, the kinetic sensitivity, and the variability of the kinetic sensitivity in 31 eyes of 31 young healthy participants. Automated kinetic perimetry was performed using an Octopus 900 perimeter with Goldmann stimuli III4e, I4e, I3e, I2e, and I1e. The participants underwent testing at 14 predetermined meridians for each stimulus, with velocities of 2°, 3°, 4°, 5°, and 10°/s; each velocity was tested twice. The test duration, kinetic sensitivity, and variability of kinetic sensitivity were compared among the stimulus velocities. Twenty-nine eyes from 29 participants were analyzed, and two participants were excluded. The test durations at the velocities of 2°, 3°, 4°, 5°, and 10°/s were negatively correlated with the stimulus velocity (p<0.01). The variability of the kinetic sensitivities did not significantly differ among the stimulus velocities. The kinetic sensitivities at 2° and 3°/s did not differ significantly for all stimuli. However, those at 4°/s decreased for III4e, I4e, and I1e (p<0.05), and those at 5° and 10°/s decreased for all stimuli (p<0.05) compared with those at 2° or 3°/s. Although the test durations for each stimulus velocity were negatively correlated with the stimulus velocities, a stimulus velocity of 3° or 4°/s might be recommended for automated kinetic perimetry based on the changes in the kinetic sensitivity. As this study included only young participants, further studies in elderly participants may also be necessary.

Physiologic statokinetic dissociation is eliminated by equating static and kinetic perimetry testing procedures

“…Stimulus velocity has been shown to be an important factor in kinetic perimetry, and recommended velocities may vary from 28/s (Wabbels & Kolling, 2001) to 48/s . The rate of movement has implications for reaction time, perceptual smear, variability, and hence isopter limits (Burr, 1980;Hirasawa, Shoji, Okada, Takano, & Tomioka, 2014;Westheimer & Wehrhahn, 1994). For practical reasons, we chose a 48/s stimulus as we wished to equate the stimulus durations for each condition, which meant that the stimulus travelled approximately 0.88, which was approximately equal to the magnitude of error due to reaction time cited by Hudson and Wild (1992) although still able to be discerned as a moving, rather than static, target (Westheimer & Wehrhahn, 1994;see Supplementary Material).…”

Effects of mydriasis and miosis on kinetic perimetry findings in normal participants

“…The Goldmann stimulus sizes and intensities of III4e, I4e, I3e, I2e, and I1e were used. The stimulus velocity was 3°/s according to a previous investigation [15], and the stimuli were presented in the following order: III4e, I4e, I3e, I2e, and I1e. Figure 1 shows the measurable area of the perimeter and the starting locations of a moving stimulus.…”

Effects of Different Levels of Intraocular Stray Light on Kinetic Perimetry Findings

“…Goldmann stimulus sizes and intensities of III4e, I4e, I3e, I2e, and I1e were used for measurement. The stimulus velocity was 3°/sec based on a previous investigation[ 9 ], and the stimuli were presented in the following order: III4e, I4e, I3e, I2e, and I1e. However, the starting locations with a moving stimulus were presented randomly for each stimulus.…”

“…The stimuli were presented randomly from the extreme periphery of the normal age-corrected kinetic sensitivity to the center. The fixation of each participant in this study was monitored using a display as described in previous reports[ 9 , 11 , 26 – 30 ]. Although the Octopus 900 Perimeter device adjusts for reaction time by adjusting the isopter area according to the response time for the stimulus presentation, we did not adjust the reaction time in this study because kinetic sensitivity with each density of opacity was not compared between participants (inter-participant); it was only evaluated for each participant (intra-participant).…”

“…To remove this bias, a few automated kinetic perimeters have been developed[ 5 – 8 ]. Using automated kinetic perimeters, researchers have been able to examine the optimal stimulus velocity[ 9 ], learning effect, and repeatability in normal participants[ 10 ], and to determine the effect of optical defocus on kinetic perimetry findings[ 11 ].…”