Abstract
Purpose:
To evaluate the dynamic changes of optical quality in patients with dry eye disease (DED) using a double-pass system.
Methods:
Twenty seven patients with DED and 35 control subjects were included in this study. Each patient underwent an evaluation of ocular surface disease symptoms using the Ocular Surface Disease Index (OSDI), tear film break-up time (TBUT), corneal and conjunctival staining (Oxford scale), and Schirmer’s test. DED severity was graded according to the 2007 Dry Eye Workshop into two groups: mild DED (12) and severe DED (15). Using the tear film analysis program of the Optical Quality Analyzing System (OQAS), the objective scatter index (OSI) was recorded every 0.5 second within an examination time of 20 seconds. This evaluation was performed for all subjects who were asked to blink freely. Several parameters including ΔOSI/time and blinking rate were established to evaluate the dynamic alteration of optical quality. Dry eye and optical quality parameters were compared between the DED and control groups. The correlations between DED and optical quality parameters were also evaluated.
Results:
DED patients had significant alterations of optical quality compared to control subjects. The ΔOSI/time was significantly increased in the mild DED group (0.092 ± 0.177; P = 0.006) and severe DED group (0.175 ± 0.176; P < 0.001) compared with control subjects (0.004 ± 0.022). The blinking rate was also significantly increased in the mild DED group (4.400 ± 3.334; P = 0.001) and severe DED group (7.083 ± 4.188; P<0.0001) compared with control subjects (1.343 ± 1.434). Optical quality parameters were not correlated to any of the DED clinical parameters (OSDI, TBUT and Schirmer’s test). Blinking rate was correlated to OSDI (r = 0.402; P = 0.038).
Conclusions:
The double-pass system allowed monitoring the dynamic changes of optical quality in patients with DED. DED patients had significant dynamic alterations of the quality of vision but these changes were not correlated to DED clinical tests. Optical quality should be evaluated in patients with DED as its alterations could not be determined from the classical DED tests.
Keywords: 486 cornea: tears/tear film/dry eye