Posters

Influence of aging on pachymetric mapping in normal eyes

Poster Details

First Author: T.Hiraoka JAPAN

Co Author(s):    Y. Ueno   M. Miyazaki   M. Ito   T. Oshika     

Abstract Details

Purpose:

To evaluate corneal thickness profile with anterior segment optical coherence tomography (AS-OCT) in normal subjects, and to analyze a correlation between the directional difference in corneal thickness and age.

Setting:

University of Tsukuba Hospital and Ito Eye Clinic.

Methods:

Corneal thickness was measured across the cornea with AS-OCT (CASIA, Tomey) and a pachymetric map was made in 948 eyes of 509 normal subjects (251 men and 258 women), ranging in age from 6 to 93 years (mean ± standard deviation, 53.8 ± 24.1 years). The corneal thicknesses on the annular ring of 3mm diameter around the corneal apex were averaged in each quadrant (superior, inferior, nasal, and temporal), and compared among 4 quadrants. The sum of corneal thicknesses in the vertical direction (superior quadrant + inferior quadrant) and in the horizontal direction (nasal quadrant + temporal quadrant) was also calculated. Subsequently, the difference in corneal thickness between the vertical and horizontal directions was analyzed in relation to age.

Results:

The cornea was the thickest in the superior quadrant in 800 eyes (84%), and the thinnest in the temporal quadrant in 688 eyes (73%). In 521 eyes (55%), the superior quadrant was the thickest, followed in descending order by the nasal, inferior, and temporal cornea. The sum of corneal thickness in the vertical direction was greater than that in the horizontal direction in 943 eyes (99%). The difference between them was 11.0 ± 5.8 µm, and showed a significant positive correlation with subjects' age (r = 0.525, P < 0.0001).

Conclusions:

In normal eyes, cornea is thicker in the vertical direction than in the horizontal direction, and the directional disparity increases with age. Therefore, it is quite important to consider the effects of corneal thickness profile on total astigmatism especially in elderly patients. FINANCIAL INTEREST: NONE