Abstract
Purpose :
An understanding of patients’ visual disability is needed to precisely measure patient-relevant outcomes of Descemet membrane endothelial keratoplasty (DMEK) in Fuchs dystrophy. In this study, we examined the association between corneal optics and visual disability using our validated Vision and Functional Corneal Health Status (V-FUCHS) instrument in Fuchs dystrophy patients before and after DMEK.
Methods :
In this prospective study, we assessed visual disability in patients with advanced Fuchs dystrophy before DMEK in the first or second eye using V-FUCHS. We previously validated and translated V-FUCHS to German. Rasch model-based mean logit scores of V-FUCHS for the Visual Acuity Factor and the Glare Factor were calculated. Preoperatively, best spectacle-corrected high-contrast visual acuity after subjective refraction (ETDRS charts) and glare (in straylight logit, C-Quant) were measured. Age-adjusted linear regression models were used to assess associations of V-FUCHS scores and optics. Differences in V-FUCHS scores 12 months after uncomplicated DMEK were calculated.
Results :
In total, 90 Fuchs dystrophy patients before DMEK and 51 patients after uncomplicated DMEK in one eye participated in this study (median age 70 years [IQR 64–78], 62% female). V-FUCHS Glare Factor and Visual Acuity scores were more negative (indicating less difficulty) after one endothelial keratoplasty (mean, -0.3; 95% CI, -0.6 to -0.1; and -0.3; 95% CI, -0.6 to 0) compared to untreated Fuchs dystrophy. In age-and EK-status adjusted multivariable models, high glare was associated with worse mean Glare scores (+1.0 logit score per 1.0 straylight logit increase; 95% CI, 0.3 to 1.9 p = 0.011), independent of visual acuity. High visual acuity was associated with better mean Visual Acuity scores (-0.3 logit score per 10 EDTRS letter increase; 95% CI -0.4 to -0.1; p = 0.005), independent of glare. In a subgroup for which post-DMEK data is already available (median, 11 months), median Glare and Visual Acuity scores improved by -0.7 (IQR, -1.9 to -0.3) and by -1.0 (IQR, -2.1 to -0.4; n = 33).
Conclusions :
V-FUCHS factors assess visual disability in Fuchs dystrophy specifically related to glare and visual acuity before and after EK. Acuity and Glare Scores improve after EK. V-FUCHS scores may help identifying those patients at need for EK und assessing outcomes.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.