[Effect of donor graft characteristics on clinical outcomes in Descemet stripping automated endothelial keratoplasty (DSAEK)].

Introduction: The purpose of our study was to evaluate the progression of lamellar corneal grafts after endothelial keratoplasty by Descemet stripping automated endothelial keratoplasty (DSAEK) and the effect of their characteristics on the clinical and functional results.
Materials and Methods: This was a prospective study in which 74 patients who had undergone endothelial keratoplasty by DSAEK were included. The corneal grafts were obtained from a French tissue bank and were delivered in a preservation medium containing a deturgescent agent (Corneajet ^® or Stemalpha 3 ^® ). Pachymetry of the corneal graft was measured ex vivo by ultrasonic pachymetry prior to dissection, then after the 1st or 2 ^nd cut as necessary. Corrected visual acuity in logMAR, total graft pachymetry, measured by anterior segment OCT (Spectralis ^® HRA+SDOCT, Heidelberg engineering, Inc., Heidelberg, Germany) and corneal density (Pentacam ^® , Oculus, Inc., Wetzlar, Germany) were obtained for each patient preoperatively, at D5, M1, M3, M6, M9 and M12.
Results: Overall, 74 corneal grafts, from donors of mean age 69.7±13.3 years (37 to 92 years) were transplanted into 67 patients aged 70.3±12.1 years. Predissection pachymetry was statistically significantly thicker in the case of short deturgescence time (r=-0.383, P=0.001). For the same deturgescence time, predissection pachymetry was statistically significantly thicker in the Stemalpha 3 ^® medium (691±89μm for Corneajet ^® vs. 760±100μm for Stemalpha 3 ^® , P=0.01), with the same final pachymetry (168±31μm vs. 166±25μm, P=0.833). Graft pachymetry and total corneal pachymetry decreased significantly between the preoperative measurement and M12 (168±29μm vs. 92±57μm, P=0.0008 et 665±124μm vs. 566±73μm, P=0.027 respectively). Preoperative endothelial cell density (2938±418 cells/mm ² ) did not correlate with postoperative visual acuity. There was a positive correlation between visual acuity at D5 and donor age (r=0.3, P=0.04). Postoperative visual acuity correlated positively with preoperative visual acuity (P<0.05). Corneal densitometry was statically higher than normal postoperative densitometry. Corneal density at M1 correlated positively with time since obtaining the donor tissue (r=0.373, P=0.043). There was no significant difference between the sub-groups of over or under 130μm. Seven patients experienced graft failure with no statistically significant graft risk factor.
Discussion: The preservation medium affects predissection pachymetry with no consequence on clinical results. In our study, preoperative visual acuity and donor age were correlated with visual acuity after DSAEK.
Conclusion: Although donor age was associated with better visual acuity at D5, the other donor characteristics had no effect on clinical results.
(Copyright © 2016 Elsevier Masson SAS. All rights reserved.)