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Updated: Jan 22, 2026

Corneal Donor Tissue Preparation for Descemet's Membrane Endothelial Keratoplasty
Published on: September 17, 2014
Spatial Analysis of Corneal Densitometry, Thickness Profile, and Volume Distribution After Uneventful Descemet
Apostolos Lazaridis1, Elefterios Giallouros1, Walter Sekundo1
1Department of Ophthalmology, Philipps University of Marburg, Germany.
Purpose:
To present normative corneal densitometry (CD), thickness (CT), and volume (CV) after uneventful Descemet membrane endothelial keratoplasty (DMEK).
Methods:
Medical records of 212 consecutive surgeries were reviewed. One hundred cases without intraoperative and postoperative complications were included (group 1). Scheimpflug CD of the optically relevant 0- to 2-mm zone and 2- to 6-mm annulus, CT at the 2-, 4-, and 6-mm rings, and CV at the 3-, 5-, and 7-mm zones were evaluated preoperatively and at 3, 6, 12, and 24 months postoperatively. The 24-month results were compared with an age-matched group of uncomplicated pseudophakic eyes (group 2; n = 20) and a group of healthy, young subjects (group 3; n = 30).
Results:
Total CD at 0 to 2 mm was 33.9 ± 10.7 grayscale units preoperatively and decreased to 20.3 ± 4.7 at 24 months (P < 0.001), being significantly higher compared with both control groups (P ≤ 0.026). Total CD at 2 to 6 mm was 27.9 ± 8.1 preoperatively and decreased to 20.2 ± 4.6 at 24 months (P < 0.001), showing no statistically significant difference compared with group 2 (P = 0.061). At 24 months, group 1 showed a similar central CT, CT at the 2-mm and 4-mm rings compared with group 2 (P ≥ 0.440); however, CT at 6 mm increased significantly (P = 0.008). CV at 3, 5, and 7 m decreased significantly at 24 months (P < 0.001), showing no significant differences compared with both control groups (P ≥ 0.122).
Conclusions:
Twenty four months after uneventful DMEK, CT within the central 4-mm zone and CV at the 3-, 5-, and 7-mm zones were similar to uncomplicated pseudophakic eyes. The total CD at the 0- to 2-mm zone and midperipheral CT at the 6-mm ring were higher compared with the pseudophakic controls.
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