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

<div><p>Purpose</p><p>To evaluate the effect of different levels of intraocular stray light on kinetic perimetry findings.</p><p>Methods</p><p>Twenty-five eyes of 25 healthy young participants were examined by automated kinetic perimetry (Octopus 900) using Goldmann stimuli III4e, I4e, I3e, I2e, and I1e. Each stimulus was presented with a velocity of 3°/s at 24 meridians with 15° intervals. Four levels of intraocular stray light were induced using non-white opacity filter (WOF) filters and WOFs applied to the clear plastic eye covers of the participants. The visual acuity, pupil diameter, isopter area, and kinetic sensitivity of each meridian were analyzed for each WOF density.</p><p>Results</p><p>Visual acuity deteriorated with increasing WOF densities (p < 0.01). With a visual acuity of 0.1 LogMAR units, the isopter areas for III4e, I4e, I3e, I2e, and I1e decreased by -32.7 degree² (-0.2%), -255.7 degree² (-2.6%), -381.2 degree² (-6.2%), -314.8 degree² (-12.8%), and -59.2 degree² (-15.2%), respectively; kinetic sensitivity for those stimuli decreased by -0.1 degree (-0.1%), -0.8 degree (-1.4%), -1.6 degree (-3.7%), -2.7 degree (-9.7%), and -1.7 degree (-16.2%), respectively. The pupil diameter with each WOF density was not significantly different.</p><p>Conclusion</p><p>Kinetic perimetry measurements with a high-intensity stimulus (i.e., III4e) were unaffected by intraocular stray light. In contrast, measurements with the I4e, I3e, I2e, and I1e stimuli, especially I2e and I1e, were affected. Changes in the shape of the isopter resulting from opacity must be monitored, especially in cases of smaller and lower-intensity stimuli.</p></div

Sealed clear plastic eye cover with applied white opacity filters (WOFs).

<p>From left to right, non-WOF filter (Grade 0) and WOF densities of 0.8 (Grade 1), 0.4 (Grade 2), and 0.1 (Grade 3) are presented.</p

Measurable area and starting locations with a moving stimulus at each meridian.

<p>The Octopus 900 perimeter device can measure the area outlined by the dashed line. The starting locations with a moving stimulus at each meridian are depicted using the III4e stimulus as an example. The stimulus is presented randomly on each meridian from the extreme periphery of normal age-corrected kinetic sensitivity to the center. If the normal age-corrected kinetic sensitivity is outside the measurable area (dashed line), the starting location is set to the extreme end of the measurable area on the same meridian. The I4e, I3e, I2e, and I1e stimuli were also measured using the same method.</p

Demographic data and ocular characteristics of the participants.

<p>Demographic data and ocular characteristics of the participants.</p

Deterioration in the isopter area per 0.1 LogMAR unit at each stimulus.

<p>Colored dots indicate deterioration in the isopter area per 0.1 LogMAR unit for each participant and the dotted lines indicate approximate straight lines.</p

Kinetic sensitivity at each meridian of each stimulus under Grades 0 to 3.

<p>Each plot was expressed as an average value for all participants. The mean visual acuity (logarithmic minimum angle of resolution, LogMAR) and mean kinetic sensitivity measured for each stimulus are shown in the lower middle and right, respectively. The symbols * and ** indicate that the kinetic sensitivity significantly decreased with p < 0.05 and 0.01 compared to the baseline Grade 0, respectively.</p