Correlations between Quality of Vision, Higher Order Aberrations and Non-Invasive Keratographic Tear Film Break-Up Time in Pseudophakic Eyes after Uncomplicated Phacoemulsification

Abstract

Aims: In this study, we aimed to investigate the intercorrelations between tear film break up time, measured non-invasively using non-invasive keratographic break-up time (NIKBUT), higher order aberrations (HOA) and quality of vision (QoV) in pseudophakic patients.
 Study Design: Cross-sectional.
 Methods: Thirty-five pseudophakic aged patients aged 50 years or older, and 35 control phakic patients aged 17 to 23 years with corrected visual acuity of 20/20 were included in this study. All subjects underwent similar examination including QoV questionnaire, aberrometry to measure HOA, and NIKBUT. HOA was measured with the OPD-Scan/ ARK 10000 corneal analyzer (Nidek CO. Ltd), expressed as Root Mean Square (RMS) HOA and NIKBUT was assessed using non-invasive TF-Scan module Keratograph 5M (K5M), equipped with modified tear film scanning function (Oculus, Wetzlar, Germany). Statistical analysis was performed to find the correlation between NIKBUT, HOA and QoV.
 Results: Patients in the pseudophakic group were significantly older (median age 66 vs. 20 years; P<0.01), had shorter NIKBUT (10.5 vs. 17.2; P<0.01), lower QoV score (1.63 vs. 0.68; P=0.04), and higher RMS HOA (0.5 vs. 0.26; P<0.01) compared to control group. NIKBUT was inversely correlated with RMS HOA (r = -0.19; p = 0.03) and RMS HOA was significantly correlated with QoV, even after adjustment for age and gender (r = -0.21; P0.04). NIKBUT <9.93s was correlated with lower QoV. The area under the curve was 0.81 (95% CI = 0.67 – 0.95, p = 0.012), and had 100% sensitivity and 61% specificity.
 Conclusion: Shorter NIKBUT was correlated with greater HOA and greater HOA was correlated with lower QoV. NIKBUT value of shorter than 9.93s could potentially predict pseudophakic patients who will likely experience visual symptoms leading to decreased QoV; thus, the use of artificial tears might be beneficial.