Impaired Saccadic Eye Movement in Primary Open-angle Glaucoma

Abstract

Purpose: Our study aimed at investigating the extent to which saccadic eye movements are disrupted in patients with primary open-angle glaucoma (POAG). This approach followed upon the discovery of differences in the eye-movement behavior of POAG patients during the exploration of complex visual scenes.Methods: The eye movements of 8 POAG patients and 4 healthy agematched controls were recorded. Four of the patients had documented visual field scotoma, and 4 had no identifiable scotoma on visual field testing. The eye movements were monitored as the observers watched static and kinetic targets. The gain, latency, and velocity-peak latency of the saccades recorded were then analyzed.Results: In POAG patients, with abnormal visual fields, watching a static target, the saccades were delayed and their accuracy was reduced, compared with those of normal observers. In POAG patients, with normal and abnormal visual fields, watching a kinetic target, a task involving precise motion analysis, the latency and accuracy of the saccades were impaired, compared with those of normal observers.Conclusions: Our findings suggest that POAG alters saccade programming and execution particularly in the case of moving targets.

Eye movements and reading in glaucoma: observations on patients with advanced visual field loss

“…Evidence is presented that differences in eye movements might explain some of the large variability in reading rates exhibited by these patients, and may help provide a plausible mechanism as to why some, but not all, glaucoma patients have difficulties with reading. This study also adds to emerging evidence of eye movements being a useful way of understanding the functional consequence of glaucoma [30][31][32][33].…”

Effect of glaucoma on eye movement patterns and laboratory-based hazard detection ability

“…Another potential reason for the decrease in saccadic amplitudes in glaucoma is that the damage to the retinal ganglion cells indirectly leads to neurological signal deficits in the areas of the brain involved in saccadic control [56, 57]. Indeed, it has been demonstrated that patients with glaucoma, even among those without any clinically-measurable visual field defects, exhibit more saccadic errors [58, 59], including reduced saccade amplitudes and accuracy, particularly when viewing moving targets [59]. Conversely, other HPT [15] and non-driving studies [22–24] have failed to find significant reductions in saccade amplitudes among adults with glaucoma.…”

Disrupted Eye Movements in Preperimetric Primary Open-Angle Glaucoma

“…[22][23][24] Compensatory oculomotor behavior, however, may not be the sole mechanism contributing to aberrant eye movements in POAG, as excessive saccades have also been reported when visual targets were displayed into unaffected visual field areas in POAG patients. 25 Furthermore, preliminary findings by Lamirel and colleagues, 25 suggest that saccadic eye movements can be altered at very early stages of POAG, with no detectable visual field deficit.…”