Correlation Between Postoperative Central Corneal Thickness and Endothelial Damage After Cataract Surgery by Phacoemulsification

Abstract

Purpose: To study the correlation between postoperative corneal edema and endothelial cell loss after cataract surgery by microcoaxial phacoemulsification.

Methods: Eighty-five eyes of 85 consecutive patients with mild cataract (up to C5, N4, and P5: per LOCS III classification) were included in a prospective study from September 2014 to November 2014. Eighty-five eyes were necessary to obtain a precision of 0.15 for computation of the Pearson correlation coefficient. Pachymetry and endothelial cell density measurements were taken preoperatively, 2 hours after surgery, and 4 days, 15 days, and 1 month after surgery using CEM-530 noncontact specular microscopy (Nidek CO Ltd, Japan). Every surgery was performed using the Stellaris device (Bausch & Lomb, Bridgewater, NJ) in a microcoaxial mode with 2.2-mm incisions.

Results: Mean age was 73 ± 2.1 years, with 41 women (48%) and 44 men (52%). The mean surgical time was 8 ± 5.5 minutes, and the mean effective phacoemulsification time was 7 ± 3.7 seconds. Mean central corneal thickness augmentation was 46.68 ± 10 μm (8.39%) 2 hours after surgery, 10 ± 18 μm (1.8%) 4 days after surgery, and only 0.76 ± 11.4 μm (0.1%) 15 days after surgery. Mean endothelial cell loss was 3.0 ± 1.5% at 2 hours, 9.0 ± 3.3% at D4, 10 ± 4.6% at D15, and 11 ± 4.7% at 1 month. At D4, significant endothelial loss (>15%) was mostly related to significant immediate corneal edema (>15%), whereas low postoperative edema (<5%) did not lead to significant endothelial loss (loss <5%). At D15 and D30, endothelial cell loss seemed to be closely correlated with immediate postoperative edema (Pearson correlation coefficient between central corneal edema at H2 and endothelial cells loss at 1 month: r = 0.4, P < 0.0001).

Conclusions: Postoperative corneal thickness measurement may therefore become a marker of endothelial damage after phacoemulsification.