Effect of Intraocular Forward Scattering and Corneal Higher-Order Aberrations on Visual Acuity after Descemet’s Stripping Automated Endothelial Keratoplasty

Abstract

PurposeTo assess the relationship of intraocular forward scattering and corneal higher-order aberrations (HOAs) with best spectacle corrected visual acuity (BSCVA) after Descemet’s stripping automated endothelial keratoplasty (DSAEK), and to compare these parameters between DSAEK and non-Descemet’s stripping automated endothelial keratoplasty (n-DSAEK) groups.MethodsThis retrospective study enrolled thirty eyes of 30 consecutive patients who underwent standard DSAEK, and who underwent successful phacoemulsification with intraocular lens implantation before DSAEK. The mean age at the time of surgery was 71.7 ± 10.4 years. We quantitatively evaluated the objective scattering index (OSI) using the double-pass instrument (OQAS II, Visiometrics) and corneal HOAs using Hartmann-Shack aberrometry (KR-9000PW, Topcon) 3 months postoperatively.ResultsThe mean OSI, corneal HOAs, and logMAR BSCVA 3 months after DSAEK were 7.91 ± 3.58, 0.43 ± 0.27 μm, and 0.32 ± 0.25, respectively. We found a significant correlation between the OSI and logMAR BSCVA (Spearman correlation coefficient r=0.714, p<0.001), but no significant association between corneal HOAs and logMAR BSCVA 3 months postoperatively (r=0.209, p=0.267). We found no significant differences in any postoperative parameters between the DSAEK and n-DSAEK groups (p>0.05).ConclusionsOur pilot study demonstrated that the postoperative corrected visual acuity was significantly correlated with intraocular forward scattering, but not with corneal HOAs in post-DSAEK eyes, suggesting that intraocular forward scattering plays a more essential role in postoperative visual performance than corneal aberrations after DSAEK. The detailed visual performance, such as HOAs and intraocular scattering, after n-DSAEK appears to be essentially equivalent to that after DSAEK.

Double-Pass Retina Point Imaging for the Evaluation of Optical Light Scatter, Retinal Image Quality, and Staging of Keratoconus

“…DPRPI has been successfully used to objectively classify the maturity of cataracts. 20, 22 A significant correlation between OSI and logarithm of the minimum angle of resolution (logMAR) but not between the size of higher order corneal aberrations and logMAR in patients status post corneal transplant has also been observed 23 , indicating DPRPI may be superior to Hartmann-Shack aberrometry in these cases. Encouragingly, OSI has been shown to detect corneal surface abnormalities; elevated OSI was observed over a 20 second course of no blinking in dry eye patients compared to no changes in controls.…”

Effect of Light Scattering and Higher-order Aberrations on Visual Performance in Eyes with Granular Corneal Dystrophy

“…Hong et al demonstrated using the Fourier domain optical coherence tomography (OCT) that the linear deposits were located most deeply in the cornea, followed by granular deposits and diffuse haze moving anteriorly in eyes with GCD 8 . We previously demonstrated that the OSI was significantly associated with visual performance not only in normal eyes 9 , but also in post-descemet’s stripping automated endothelial keratoplasty eyes 10 . We consider that the objective assessment of forward scattering is of clinical help for predicting visual performance even in eyes with GCD.…”

“…Corneal HOAs were also measured with the Hartmann-Shack aberrometry (KR-9000, Topcon, Tokyo, Japan) for a 4-mm pupil, as described previously 10 . The root-mean-square of the third-order Zernike coefficients was utilized to represent third-order aberrations, the root-mean-square of the fourth-order coefficient to represent fourth-order aberrations.…”

Quantification of forward scattering based on the analysis of double‐pass images in the frequency domain

“…), and significant correlations have been found between the OSI and the logMAR in patients after corneal transplantation (Kamiya et al. ). The OSI compares the integrated intensity contained in a ring between 0.20° and 0.33° (degrees), that is, between 12 and 20 min of arc, with the integrated intensity contained in the central area of the DP image within 1 min of arc.…”