Identification of the association of specific signs of dry eye disease with specific visual function; deficits may allow for more targeted approaches to treatment. The purpose of this study was to explore the association of dry eye signs; and symptoms with visual acuity (VA) and contrast sensitivity in the Dry Eye Assessment and Management study.
Poor visual acuity rather than contrast sensitivity promotes vision-related symptoms in dry eye; according to a recent study published in Optometry & Vision Science. “Contrast sensitivity is a candidate because it is a sensitive indicator of visual function; and ocular disease progression. However, although previous studies have shown that contrast sensitivity is a sensitive measure of the effects of dry eye on visual function; very few have assessed which particular clinical signs impact this measurement,” Szczotka-Flynn and colleagues wrote.
Visual acuity and contrast sensitivity
However, the researchers conducted a secondary cross-sectional analysis using baseline data; from the Dry Eye Assessment and Management study involving 487 participants (974 eyes). Ocular Surface Disease Index (OSDI); high-contrast logMAR visual acuity and contrast sensitivity some of the factors measured in the study.
However, the association between visual acuity and contrast sensitivity with OSDI score and each dry eye; sign assessed by using generalized linear models. The linear models included age; refractive error status and cataract status. Generalized linear models that included age, refractive error status, and cataract status. But the Hochberg procedure was used to account for multiple comparisons. The results suggested that poor visual acuity significantly associated; with a poor mean score on the OSDI vision subscale (39.4 for visual acuity 20/32 or worse vs. 32.4 for visual acuity 20/16 or better; adjusted linear trend, P = .02).
Complaints in dry eye
Severe meibomian gland plugging and abnormal secretions found to be related to a poor; mean log contrast sensitivity (1.48 for severe vs. 1.54 for not plugged [P =.04] and 1.49 for obstructed vs. 1.57 for clear [P = .002], respectively). In addition, longer tear breakup time was linked to better mean log contrast sensitivity (1.57 for tear breakup time greater than 5 seconds and 1.51 for tear breakup time 2 seconds or less, P < .0001).
“In conclusion, our study found that poorer visual acuity; rather than worse contrast sensitivity drives visual symptoms and complaints in dry eye. However, contrast sensitivity measurements are more sensitive to worse; tear film stability measures (such as tear breakup time and meibomian gland plugging) than standard visual acuity assessments,” Szczotka-Flynn and colleagues wrote. “Future studies that examine how specific ocular signs affect various measures of visual function would be helpful in elucidating these relationships and could, in turn, guide therapies.”