Correlation of Eye Tracker reading Patterns and Visual Field Defects of Glaucoma Patients

Abstract

Purpose : To correlate glaucoma patients’ reading performance patterns (through reading speed, saccades, fixation) and corresponding visual field defect.

Methods : This is a prospective case control study including 57 glaucoma patients. Demographic, systemic and ophthalmologic information was obtained. All patients had at least 0.5 logMAR best corrected visual acuity (BCVA) on the left eye. Eye Tracker data were extracted using the Tobii Studio appurtenance software. Participants went through a reading performance test on MNRead translated and validated in Portuguese. 3 interventions were made: 1. Font size, 2. Line spacing and 3. Contrast. 3 parameters of the eye tracker were evaluated: 1. Reading duration (total time of fixation/characters), 2. Fixation (fixation/characters), 3. Mean fixation duration (total time of fixation/number of fixation). Standard Automated Perimetry (SAP) was performed and analyzed. Visual field defects were classified according to the Ocular Hypertension Treatment Study (OHTS).

Results : Glaucoma patients had a mean age of 66.54 (±13.75) and 38 (51.35%) had first degree. BCVA in the left eye was 0.18 (±0.16) logMAR. Mean Deviation (MD) of the left eye was -10.67 (±8.64) dB. There was a strong correlation between central visual field defect and reading speed (p=0.014). Other eye tracker and other types of visual field defects are being analyzed.

Conclusions : This study reveals that central vision impairment strongly impacts the reading performance in glaucoma patients. Previous studies from this group showed decreased reading speed and more number of saccades and fixations in glaucoma patients compared to control patients even when central vision is not impaired. It is known that glaucoma patients usually do not have central vision impairment. So we aim to further analyze the peripheral and paracentral visual field defects and its impact on reading performance.

This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024.