Central Corneal Thickness Changes after Phacoemulsification

Abstract

Purpose: To determine when the mean central corneal thickness (CCT) returns
to normal values after uneventful phacoemulsification.
Material and Methods: This was a prospective case series. The study was
carried out at the Section of Ophthalmology, Department of Surgery, Aga Khan
University Hospital, Karachi. Eyes scheduled to undergo phacoemulsification
during December 2011 – March 2012 were eligible to be included. Eyes with
corneal degenerations, dystrophies or high pre-op astigmatism were excluded. A
structured proforma was used to collect data on sociodemographics, comorbids,
visual acuity, and CCT before surgery and 1 day, 1 week and 1 month after
surgery. Changes in the mean CCT over time were measured using repeated
measures Analysis of Variance (ANOVA) was done.
Results: Eighty one eyes were included in the study. The mean (±SD) age of
the participants was 58.30 (± 10.04) years. The majority of them (58.0%) were
women. Sixty two (76.5%) eyes completed the last follow-up and were included
in the final analysis. The mean CCT was 542.81 ± 34.85 mm before surgery
which markedly increased to 595.27 ± 43.78 mm 24 hours after surgery, but
decreased to 565.82 ± 38.30 at one week, and returned to normal baseline
values (544.42 ± 28.95) in almost all operated eyes in 1 month time. There was
no statistically significant difference in the mean CCT before surgery and at 1
month (p=0.685).
Conclusion: The mean CCT substantially increasing after post-operative
uneventful cataract surgery but returns to normal baseline values in almost all
operated eyes in 1 month time. IOP measured during this period may be falsely
higher than the true values due to increased CCT.
Key words: central corneal thickness, phacoemulsification, cataract surgery