Abstract
Introduction: A recent epidemiological study indicated that DE patients report that reading is a difficult task (odds ratio 3.64, p <0.0001). In addition, studies have demonstrated that DE patients read slower than normal controls. However, there are no reported studies that have monitored eye movements of DE patients while they read. The purpose of this study was to investigate if specific eye movement parameters are altered during reading in DE patients. Methods: Seventeen subjects took part in this study (10 DE (age 63.2 ± 6.16) and 7 normal controls (age 61.3 ± 7.01)). All subjects had a complete eye exam with DE work up. DE patients had both subjective and objective signs of a DE in compliance with the recommendations of the 2007 International Dry Eye Workshop. The Tobii TX300 Eye Tracker monitored eye movements (saccades, fixations, regressions, and blinks) during reading. The Wilkins Rate of Reading Test was used to determine reading rate. Results: There were no significant differences between DE patients and normal controls for saccade amplitude, saccade velocity, fixation time, number of saccades or fixations, or number of regressions (all p values > 0.05). The reading rates were also not different between the groups (DE = 152.6 ± 13.4 wpm, Control =159 ± 13.2 wpm, p = 0.34). The DE patients had more total blinks (DE = 21.0 ± 8.18, Control = 5.29 ± 2.69, p <0.001) and a shorter inter-blink interval (DE = 3.3 ± 2.04 sec, Control = 14.9 ± 8.54 sec, p = 0.013) than the normal controls. Conclusions: The increased number of blinks and the shorter inter-blink interval while reading may result in a slower reading rate and a greater difficulty reading for DE subjects.
Meeting abstract presented at VSS 2014