Comparison of Saccadic Eye Movements Among the High Tension Glaucoma, Primary Angle Closure Glaucoma, and Normal Tension Glaucoma.

PRCIS Saccadic eye movements were compared between high tension, normal tension, and primary angle closure glaucoma. Saccades were differently affected between subtypes of primary glaucoma. AIM To compare saccadic eye movements in eyes with high tension primary open angle glaucoma (HTG), primary angle closure glaucoma (PACG) and normal tension glaucoma (NTG). METHODS Saccadic eye movements were recorded using Eyelink-1000 eye tracker in 52 participants: 15 HTG, 14 PACG, 8 NTG, and 15 normal controls. All participants underwent a complete ophthalmic and visual field examination. Prosaccades were measured using the gap paradigm. Prosaccades were measured at 3 target eccentricities (5,7 and 10-degree eccentricity). All prosaccade targets were projected outside the area of visual field defect. Saccade latency, average and peak velocity, and amplitude difference of the saccades were compared between glaucoma subtypes. RESULTS The mean (±standard deviation) age was lesser in controls compared to glaucoma (P=0.02). The mean age in all the glaucoma subtypes was comparable (P=0.92). The average mean deviation (MD) in PACG (-16.66±6.69) was worse (P=0.01) than in HTG (-11.56±6.08▒dB), and NTG (-9.55±3.96▒dB). The latencies were delayed, average and peak velocity were reduced and saccades were hypometric in glaucoma compared to controls (P<0.01). Between subtypes, the differences in latency (P<0.01), peak velocity (P=0.02), and amplitude (P=0.02) were significant. The saccadic eye movements were significantly different in NTG compared to other glaucoma subtypes, (post-hoc analysis; latency (HTG vs. NTG; P<0.01, HTG vs. PACG; P=0.01), peak velocity (HTG vs. NTG; P=0.02) and amplitude difference (HTG vs. NTG; P=0.02). CONCLUSION Saccadic eye movement parameters were differently affected among the glaucoma subtypes. Saccadic parameters were more affected in NTG.