Abstract
Purpose: :
Final visual acuity after Descemet stripping automated endothelial keratoplasty (DSAEK) varies vastly. The reasons for this variance are poorly understood. Optical coherence tomography (OCT) reveals focal intensity spikes within the posterior graft and recipient posterior stroma. We hypothesize that these signals correlate with specific ultrastructural properties of the posterior central stromal collagen lattice. Thus, good alignment of the intensity spikes may predict the more favorable outcomes.
Methods: :
We performed OCT imaging in 27 eyes after DSAEK. We also ascertained best spectacle corrected visual acuity and documented age at the time of surgery as well as reduced visual potential from retinal or optic nerve damage. We gauged displacement of the focal OCT intensity spikes between recipient and graft stroma. Furthermore, we measured central thickness of graft and recipient cornea. We additionally assessed graft thickness asymmetry and centering. We fitted a multifactorial linear regression model (ANOVA) to investigate whether a displacement of the OCT intensity spikes can predict the logarithmic visual acuity against the background of graft thickness, host cornea thickness, graft centration in the host and asymmetry of graft thickness.
Results: :
Follow up averaged 7.8 months. Best corrected visual acuity at end of follow up turned out 0.4+/-0.3 logMAR (mean and standard deviation). Visual acuity was statistically significantly correlated with displacement of the OCT reflectivity peaks (p=0.049) and thickness of the recipient stroma (p=0.011) but not from the other covariates.
Conclusions: :
The central posterior cornea stroma may exert unique optical properties. Both centered trephination and centered implantation of the graft may be equally important for visual acuity after DSAEK.
Keywords: cornea: clinical science • imaging/image analysis: clinical • transplantation