Abstract
Purpose :
Heijl-Krakau method, which evaluates the response to stimulation of physiologic scotoma, has been widely used for evaluating fixation stability of the standard automated perimetry test. While eye movement during visual field test causes inappropriate response to the stimuli of Heijl-Krakau method, there is a possibility that patients who has the deterioration of sensitivity near the physiologic scotoma are less likely to respond to the Heijl-Krakau stimuli, regardless of whether eye movement occurs or not. A newly developed head mounted perimetry imo<span style="font-size:10.8333px">®</span> has an eye tracking system which theoretically enable the device to present the stimuli of the Heijl-Krakau method on optic disc continuously. In this study, we compared the rate of fixation loss (FL) response between eyes with deterioration and no-deterioration of sensitivity near the physiologic scotoma.
Methods :
This study enrolled eight hundred eighty-three eyes of 445 glaucoma patients. All eyes were classified into deterioration and no-deterioration groups. Definition of the deterioration group: a sensitivity of (15,-3) test point where the physiologic scotoma corresponded was 0dB and one or more deteriorated test points (< 10dB) in 8 test points around (15,-3) test point. All patients underwent a visual field test with imo<span style="font-size:10.8333px">®</span>. We compared the rate of FL response by Heijl-Krakau method between those 2 groups.
Results :
Deterioration group was 163 eyes, and no-deterioration group was 720 eyes. In 163 eyes of deterioration group, 48 eyes showed two or more deteriorated test points. The rate of FL responses were 18.8 ± 22.4％ in the no-deterioration group and 11.4 ± 13.6％ in the deterioration group. The deterioration group was significantly smaller than the no-deterioration group (p<0.001). The rate of FL response in eyes with two or more deteriorated test points was 10.7 ± 11.7%. In the deterioration group, no significant difference was found between eyes with one deteriorated test point and two or more deteriorated test points.
Conclusions :
Our result suggests that Heijl-Krakau method is likely to underestimate FL response when subject has the deterioration of sensitivity near the physiologic scotoma.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.