Posters

Changes of corneal epithelial thickness in different regions after FS-LASIK in high-astigmatism patients

Poster Details

First Author: L.Hu CHINA

Co Author(s):    Z. Liu   M. Lin   F. Lu              

Abstract Details

Purpose:

To study the changes of corneal epithelial thickness after FS-LASIK in high astigmatism patients.

Setting:

A perspective study managed in Wenzhou Medical University Affiliated Eye Hospital

Methods:

This study involved 42 eyes of 28 patients (19 males and 9 females) with at least 2.00 D astigmatism. Corneal epithelial thickness was measured by AngioVue OCT preoperatively and postoperatively. Corneal epithelial thickness was recorded at every intersection of concentric circles and specific axes, including the astigmatic axis (K1) and the perpendicular meridian (K2). The central, paracentral and midperipheral regions were defined as the area of central 2 mm, 2-5mm and 5-7mm respectively. Corneal epithelial thickness in different axes and their correlations with preoperative diopter were analyzes.

Results:

1. The variation differed significantly between K1 and K2 in paracentral and midperipheral regions（paracenrtral：P=0.014, midperipheral：P<0.001）. 2. The epithelial thickness variation differed significantly between K1 and K2 at 2.5, 3.0 and 3.5 mm from corneal vertex (2.5mm：P=0.011，3.0mm：P<0.001，3.5mm：P<0.001). 3. The ratio of epithelial thickness changes and diopters in K1 were significantly less then K2 in central and paracentral regions (central:P<0.001，paracenrtral：P=0.003). 4. There were correlations between the epithelial thickness variation (central and paracentral regions) and preoperative diopter (central: r=0.439，paracentral: r=0.258).

Conclusions:

the corneal epithelial thickness increased significantly both in central and paracentral regions one month postoperatively in high astigmatism patients. Furthermore, the increase in astigmatism axis of paracentral region was larger than that in perpendicular meridian. Diopter was one of the factors the affected growth of corneal epithelium. The impact on the central region was greater than the paracentral region. On the contrary, the corneal epithelial thickness decreased in peripheral region, which might be due to the epithelial damage when creating flap.

Financial Disclosure:

None