Centering corneal surgical procedures

Area of Science:

• Ophthalmology
• Optical Engineering
• Surgical Navigation

Background:

• Current corneal surgical procedures often rely on visual axis for centering.
• Existing methods for defining and marking the visual axis lack precision.
• Inconsistencies in visual axis definition can lead to suboptimal surgical outcomes.

Purpose of the Study:

• To evaluate the accuracy of current corneal surgical centering techniques.
• To determine the optimal reference point for centering corneal procedures.
• To identify and quantify errors associated with visual axis-based centering.

Main Methods:

• Comparative analysis of centering methods using optical outcomes.
• Patient fixation on a coaxial point with the surgeon's sighting eye.
• Marking the cornea based on the entrance pupil center and line of sight.

Main Results:

• Centering on the line of sight and entrance pupil provides superior optical results compared to the visual axis.
• Current methods exhibit centering errors ranging from 0.5 to 0.8 mm.
• Errors stem from reliance on corneal light reflex and monocular sighting issues.

Conclusions:

• Accurate centering for corneal surgery should utilize the line of sight and entrance pupil.
• Revising centering techniques can improve precision and optical outcomes in corneal procedures.
• Proper patient fixation and entrance pupil alignment are crucial for accurate corneal marking.