Endothelial Cell Density Recorded in the Central and Sub-Incisional Areas Before and After Cataract Extraction With Phacoemulsification

Abstract

Purpose: : To monitor the endothelial cell loss in the central and sub-incisional areas after cataract surgery.

Methods: : Thirty-eight consecutive patients waiting for routine cataract surgery by phacoemulsification and eligible to become candidates were enrolled in this study. They were operated for cataract surgery with a 2.75 x 1.75 mm long corneal incision done at twelve o’clock on the superior clear cornea. After capsulorhexis and hydrodissection, the lens was emulsified, the capsular bag was irrigated and aspirated before the injection of a foldable monofocal implant in the capsular bag under viscoelastic. Endothelial cell density was measured with a Konan Robo SP-8000 specular microscope in corneal center (P1), as well as 2.3 (P2) and 4.9 (P3) mm above corneal center before and 1 month after surgery. The effect of position and time on endothelial cell density was tested with a 2-way ANOVA (2 times x 3 positions) for repeated measurements, followed by appropriate post-hoc tests for pairwise comparisons corrected for the number of tests with Bonferroni’s inequality to keep a significance level of 5%.

Results: : Before surgery, the endothelial cell density was significantly larger by 6.6% and 11.5% in the mid-peripheral (P2) and peripheral (P3) positions (p= 0.0196; p= 0.0023) than in the center, respectively. By contrast, after surgery, the endothelial cell density was significantly higher by 21.7% and by 39.5% in P1 and in P2 (p=0.0156; p=0.0256) compared with the peripheral P3 ECD, respectively. There was a significant reduction in endothelial cell density one month after cataract surgery in P1, P2 and P3 that was respectively 491 ± 571, 832 ± 482 and 1241 ± 604 cells/mm² (p=0.0008, p<<0.0001 and p<<0.0001 respectively), which represented a 17, 29 and 40% drop in ECD, compared to baseline levels.

Conclusions: : The reduction in endothelial cell density observed in the sub-incisional corneal area is much larger that what has been reported for peripheral cell loss in spite of similar central losses.

Keywords: cornea: endothelium • cataract • clinical (human) or epidemiologic studies: natural history