To assess the relationship between optical quality dynamic change using a double-pass system (OQAS-II) and tear breakup time (TBUT) in patients with dry eye disease.

Thirty patients (60 eyes) with dry eye disease in Hangzhou Xihu Eye Hospital were included in this serial case study from May 2018 to May 2019. All subjects underwent examinations as follows: TBUT under fluorescein staining, Shirmer Ⅰ test (SⅠT) under topical anesthesia, and corneal fluorescein staining. The basic objective scattering index (basic OSI), the average OSI under natural blinking within 20 s (mean OSI1), and the average OSI under non-blinking within 20 s (mean OSI2) were recorded by the OQAS-II system. The differences between mean OSI1 and basic OSI and mean OSI2 and basic OSI were recorded as ΔOSI1 and ΔOSI2, respectively. Spearman correlation analysis was used to observe the correlation between ΔOSI1, ΔOSI2, basic OSI, mean OSI1, mean OSI2, and BUT.

The average BUT was 0.93-7.05(2.56±1.02)s, the average of Shirmer Ⅰ was 11.33±7.93 mm/5 min, and corneal fluorescein staining was positive in 4 out of 60 eyes. The medians of basic OSI, mean OSI1, mean OSI2, ΔOSI1, ΔOSI2 were 0.60(0.40, 1.28), 1.22(0.68, 2.22), 2.18(1.13, 2.85), 0.41(0.25, 1.01), 1.13(0.48, 2.30. Both ΔOSI1 and ΔOSI2 had anegative correlation with BUT ( r=-0.276, P=0.033; -0.305, P=0.018), no correlation between the remaining indexex.

The OQAS II system has the potential to be a useful method to evaluate the optical quality and tear-film dynamics in patients with dry eye. When using OQAS-II to detect tear film stability, patients should be instructed to blink as little as possible to provide more valuable results.

xerophthalmia; double-pass imaging system; objective scatter index; tear break up time; Shirmer Ⅰ test