Tomographic characteristics of thick corneas

Area of Science:

• Ophthalmology
• Corneal Tomography
• Refractive Surgery

Background:

• Corneal thickness is a critical factor in refractive surgery candidacy.
• Understanding tomographic characteristics of thicker corneas is essential for accurate pre-operative assessment.

Purpose of the Study:

• To analyze tomographic features of excessively thick corneas.
• To evaluate the influence of these features on refractive surgery candidate screening.

Main Methods:

• Corneal tomography was performed on three groups of eyes based on thinnest pachymetry (TP): <500 μm, 500–580 μm, and ≥580 μm.
• Pentacam ectasia indices were compared across these groups.

Main Results:

• Eyes with TP ≥580 μm exhibited significantly higher back elevation (BE) and deviation of normality of the back elevation (Db), and a more negative Q value for the back surface (Qback) compared to those with TP 500–580 μm.
• No significant differences were found in anterior corneal indices between the groups.
• Abnormalities in BE and Db were most prevalent in the thickest cornea group (TP ≥580 μm).

Conclusions:

• Tomography of thick corneas reveals specific posterior surface abnormalities (BE, Db, Qback).
• Anterior corneal indices do not significantly differ in thick corneas.
• These tomographic findings are crucial for the accurate assessment of refractive surgery candidates with thicker corneas.