The effect of cataract surgery on the central corneal thickness

الملخص EN

Purpose: The present work aims to determine the effect of cataract surgery on the corneal thickness and compares the effect of extracapsular cataract extraction (ECCE).

and the effect of phacoemulsification on the central corneal thickness.

Methods: The present study included 50 patients (50 eyes) who were admitted at our eye department for cataract surgery in the period between October 1999 and October 2001.

The patients were divided into 2 groups.

Every group included 25 patients.

One group underwent extracapsular cataract extraction and the other group underwent phacoemulsification Differences between preoperative values and postoperative values of central corneal thickness in each group were statistically analyzed using t-test for paired data.

Differences between the two groups were analyzed using the t-test and P- alue of < 0.05 was considered statistically significant.

Corneal thickness was measured using ultrasonicpachymeter (SonomedModel 4000 P).

Results: A statistically significant increase in corneal thickness was observed in the 1st day, 7th day, and in the first month in ECCE group (group A) ; and in 1st day in phacoemulsification group (group B) .

The difference between the 2 groups in postoperative variation in central corneal thickness in 1st day, 7th day, and after 1 month was statistically significant.

In the 1st, 7th and after one month, the operation of ECCE caused more increase in the central corneal thickness than in phacoemulsification technique.

Phacoemulsification group returned to nearly normal values at about 7th day postoperatively earlier than ECCE group which returned to nealy normal values about 2 months postoperatively.

Conclusions: Changes in the corneal thickness in the immediate postoperative period are an important indicator of surgical technique and corneal endothelial damage.This study reinforces the clinical importance of measurement the central corneal thickness as a good indicator of surgical trauma to the corneal endothelium.

This study also demonstrates that phacoemulsification is a safe and effective technique that minimizes endothelial functional damage as reflected by the quick return to normal corneal thickness.