Abstract
Purpose:
To assess the impact of glaucoma on specific measures of out loud reading, including time to say individual words, interval time between consecutive words, lexical errors, skipped words, and repetitions.
Methods:
Glaucoma subjects (n=64) with bilateral visual field loss and glaucoma suspect controls (n=57) were recorded while reading an International Reading Speed Text (IReST) passage out loud. Audio recordings were evaluated by a masked evaluator to determine the start and end of each recorded word and to identify reading errors.
Results:
Glaucoma subjects demonstrated a longer duration to recite individual words [265 vs. 243 milliseconds (ms), p<0.001], a longer interval time between words (154 vs. 124 ms, p<0.001), and a longer word/interval complex (defined as the time spanned by the word and the interval preceding the word) (417 vs. 365 ms, p<0.001) than controls, but did not differ in the number of repetitions, skipped words, or lexical errors (p>0.1 for all). In multivariable analyses adjusting for age, race, sex, education, cognition, word length, and word complexity, each 0.1 decrement in log contrast sensitivity was associated with a 6.3 ms longer word time (95% CI=3.8-8.9; p<0.001), an 8.7 ms longer interval time (95% CI=5.3-12.1; p<0.001), and a 15.0 ms longer word/interval complex (95% CI=9.7-20.3; p<0.001). Additionally, severity of glaucoma damage (as determined by contrast sensitivity) was found to significantly interact with word length, word complexity, and word location at the beginning of a new line with regards to word/interval complex duration (p<0.05 for all), suggesting that word length, word complexity, and word location at the beginning of a line all had a greater effect on word/interval duration in patients with lower CS. Glaucoma severity was also associated with increased odds of making a lexical error (OR=1.20 for every 0.1 decrement in log contrast sensitivity; 95% CI=1.02-1.39, p<0.05), but not with odds of skipping or repeating a word (p>0.05 for both).
Conclusions:
Glaucoma patients have greater difficulty reciting longer and more complex words, as well as transitioning to new lines of text. Additionally, glaucoma severity is associated with a higher likelihood of making a lexical error. These problem areas may require special attention when designing methods to rehabilitate reading in patients with glaucoma.
Keywords: 568 intraocular pressure •
584 low vision •
672 reading