The influence of dry eye disease (DED) on ocular biometric measurements is unclear. We aimed to investigate the effect of DED on the repeatability of ocular biometric measurements in cataract patients. Overall, 114 eyes scheduled for cataract surgery were enrolled. Before surgery, DED parameters including tear film break-up time (BUT), corneal and conjunctival staining scores, and subjective symptoms were examined. Corneal curvature radius and axial length were assessed twice on the same day using IOLMaster-500 (Carl Zeiss Meditec), and the absolute difference between the two measurements was calculated and used as an index of measurement repeatability. The measurement repeatability of the steep meridian of corneal curvature radius was significantly worse in eyes with DED than in those without DED (p = 0.044) and was significantly associated with BUT (r = -0.206, p = 0.031). The measurement repeatability of axial length was negatively correlated with BUT (r = -0.199, p = 0.041) and positively correlated with the corneal staining score (r = 0.253, p = 0.009). In conclusion, the measurement repeatability of corneal curvature radius declined in eyes with DED. Shortened BUTs were associated with a deterioration in the measurement repeatability of corneal curvature radius and axial length.
Keywords: axial length; biometry; cataract surgery; corneal curvature radius; corneal epithelial damage; dry eye disease; repeatability; tear film break-up time; unstable tear film.