Tear Film Stability Affects Visual Acuity After Implantations of Monofocal and Multifocal Intraocular Lenses: An Evaluation by Objective Scatter Index.

Abstract

To assess the impact of tear film on postoperative visual acuity after cataract surgery to implant an intraocular lens (IOL). Tear break-up time (TBUT), Schirmer I test, objective scatter index (OSI), and uncorrected distance visual acuity (UCDVA), intermediate visual acuity (UCIVA), and near visual acuity (UCNVA) were collected 6months after cataract surgery. Fifteen eyes with monofocal (Mo-) IOLs and 15 eyes with multifocal (Mu-) IOLs from 30 subjects were included. The Mu-IOL group exhibited higher baseline OSI (1.92 ± 0.69, P < 0.001). Negative correlations-both groups: tear film-related OSI (TF-OSI) and TBUT/Schirmer I test; Mo-IOL: TBUT and logMAR UCDVA-and positive correlations-both groups: TF-OSI and baseline OSI, baseline OSI/TF-OSI and logMAR UCDVA; Mu-IOL: baseline OSI/TF-OSI and logMAR UCIVA/UCNVA-were found. Linear regression showed associations between TF-OSI and TBUT (Mo-IOL: R2=0.455, P=0.006; Mu-IOL: R2=0.454, P=0.006)/Schirmer I test (Mo-IOL: R2=0.527, P=0.002; Mu-IOL: R2=0.266, P=0.049). Multiple regression showed associations between baseline OSI (Mo-IOL: R2=0.309, P=0.032; Mu-IOL: R2=0.305, P=0.033)/TF-OSI (Mo-IOL: R2=0.332, P=0.025; Mu-IOL: R2=0.523, P=0.002)/TBUT (Mo-IOL only: R2=0.315, P=0.029) and logMAR UCDVA. TF-OSI reflects the UCDVA performance in eyes with IOLs and facilitates a better understanding of the effects of the tear film. TF-OSI offers a developmental and objective approach to assessing the changing visual performance caused by tear film after cataract surgery and IOL implantation in clinical practices.