Assessment Of Optical Zone Decentration After Corneal Refractive Laser Treatment Using Imagej Software

Assessment of a new method for measuring optical zone decentration after corneal laser surgery on post operative topography with ImageJ.

Bellecour Vision Clinic, Lyon 

Postoperative topographies from 40 eyes that underwent KLEx (keratorefractive lenticule extraction surgery) were analyzed twice in a randomized manner by three different operators to assess the repeatability and reproducibility of the new centration method for the treatment zone. For each topography, the ablation zone was identified, and the distance between the vertex (the visual axis defined on the topography) and the center of the optical zone was measured using ImageJ software.

The analysis demonstrated good repeatability. The inter-operator reliability of decentration measurements ranged from moderate to good (0.689 to 0.901), with no significant bias (<0.02mm) and concordance limits remaining within acceptable ranges for this measurement method (-0.15 to 0.21 mm).

The results indicate good reproducibility of the method, with no significant inter-operator bias, high ICC values (0.811), and agreement limits within acceptable ranges (-0.12 to -0.27), supporting its overall reliability and a good agreement.

The mean total decentration was 0.18 ± 0.08 mm (0.05 ; 0.41).

This study demonstrates the repeatability and reproducibility of a new centration assessment method in corneal refractive surgery, paving the way for the development of AI-driven automated solutions.