Eye-Tracking Reading Patterns as Correlates of Clinical Measures in Glaucoma

The purpose of this study was to make correlations between reading performance patterns - saccades, fixation and reading speed - and functional and structural exams of patients with glaucoma.

A cross-sectional study collected ophthalmologic information of primary glaucoma patients. All patients had at least 0.5 logMAR best corrected visual acuity on the evaluated eye. Aloud reading of five MNREAD slides displayed on computer screen was recorded using ISCAN Eye-Tracker software. Reading speed, number and amplitude of saccades, and number and duration of fixations were collected. Humphrey 24-2 Standard Automated Perimetry (SAP) and Cirrus Optical Coherence Tomography (OCT) data were collected to make correlations with all reading patterns.

In this exploratory analysis, a total of 57 patients with glaucoma were enrolled. Best-corrected visual acuity in the left eye was 0.18 (±0.16) logMAR. Central superior defect in the SAP had the slowest reading speed in all five slides (p < 0.05) and a greater number of saccades (p < 0.05 in three of 5 slides), and thinning of the inferior quadrant in OCT was the most associated with slower reading (p < 0.05 in 2 of five slides) and greater number of fixations (p < 0.05 in one of 5 slides). Peripheral SAP defects had correlation with shorter saccades.

SAP data had a stronger correlation to reading abnormalities compared to the OCT data. Central superior SAP damage is the most associated with abnormal reading patterns in a computer screen environment. Peripheral SAP injuries correlated with shorter saccades size.