Abstract
Purpose :
We recently described a new classification of Fuchs endothelial corneal dystrophy (FECD) that incorporates Scheimpflug imaging to detect early or subclinical corneal edema when clinically visible edema is not present. In this study, we determined the prognosis of eyes with FECD based on the tomographic findings alone, independent of central corneal thickness (CCT).
Methods :
Eyes with a range of severity of FECD were enrolled in a cross-sectional study. Cornea specialists confirmed the diagnosis of FECD (by the presence of guttae) and determined the presence or absence of definite corneal edema. Corneas were then examined by Scheimpflug imaging. Scheimpflug tomography maps were evaluated by 3 masked observers for 3 features suggestive of clinical or subclinical edema: loss of parallel isopachs, displacement of the thinnest point of the cornea, and the presence of focal posterior surface depression (towards the anterior chamber). The clinical outcomes of these eyes were reviewed to determine if FECD had progressed, defined as new onset of clinically visible edema, CCT increase >5%, or proceeding to endothelial keratoplasty (EK).
Results :
Scheimpflug tomography maps of 88 eyes (52 subjects) were evaluated; median age was 68 years (range, 42–89 years), 69% were female, and median follow-up was 48 months (IQR, 36-64 months). None of the 3 tomographic features of edema were evident in 39 eyes: 36 (92%) remained stable, 1 (3%) had an increase in CCT, and 2 (5%) subsequently underwent EK. One tomographic feature of edema was present in 3 eyes and all remained stable. Two tomographic features of edema were present in 13 eyes; 8 (62%) remained stable whereas 5 (38%) progressed (2 underwent EK). All 3 tomographic features of edema were present in 33 eyes; only 3 (9%) remained stable whereas 30 (91%) underwent clinical progression or underwent EK. There was a 10-fold relative risk (95% CI, 3.5-32, p<0.001) of progressing when 2 or 3 tomographic features of edema were present compared to when none or 1 feature of edema was present.
Conclusions :
In this study, with median follow-up of 4 years, 3 easily identifiable subjective patterns in Scheimpflug tomography maps correlated with increasing corneal thickness or progression to keratoplasty in FECD. This revised classification may help in clinical decision-making or the timing of surgical intervention.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.