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Updated: Feb 4, 2026

Corneal Donor Tissue Preparation for Descemet's Membrane Endothelial Keratoplasty
Published on: September 17, 2014
Corneal Densitometry as a Predictive Diagnostic Tool for Visual Acuity Results After Descemet Membrane Endothelial
Friederike Schaub1, Fanny Gerber1, Werner Adler2
1Department of Ophthalmology, University of Cologne, Cologne, Germany.
Purpose:
We sought to investigate correlations between preoperative corneal backscatter with visual acuity results after Descemet membrane endothelial keratoplasty (DMEK) in eyes with corneal endothelial disorders.
Design:
Retrospective interventional case series.
Methods:
The first 551 consecutive patients with DMEK at the Center of Ophthalmology, University of Cologne who had available preoperative corneal densitometry values (corneal light backscatter measured in gray scale units) measured with the Scheimpflug-based Oculus Pentacam corneal densitometry module were screened for eligibility. Best spectacle-corrected visual acuity (BSCVA) results were retrospectively correlated with densitometry data. Densitometry data were obtained in 4 corneal layers (ie, anterior, central, posterior, and total layers) and 4 annuli. Pre- and postoperative BSCVA results were correlated with densitometry data. Receiver operating characteristic analyses were performed.
Results:
Four hundred twelve eyes were available for the analyses. Visual acuity results improved significantly after DMEK surgery at 3, 6, 12, and 24 months of follow-up (P < .001). Corneal backscatter correlated moderately with preoperative BSCVA results. Moderate associations to postoperative BSCVA results could predominantly be found between densitometry values of the anterior and central layer more pronounced in the center of the cornea for all postoperative timepoints. The posterior layer correlated worst with postoperative gain in BSCVA. Receiver operating characteristic analyses revealed that the best predictive power of densitometry values was for the 2-6 mm annular zone of the cornea.
Conclusion:
Corneal backscatter in eyes with corneal endothelial disorders correlates with postsurgical BSCVA results after DMEK surgery. Therefore, early DMEK surgery seems to have a positive impact on long-term BSCVA results.
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