Abnormal corneal topography often means standard laser eye surgery is unsafe, because it may indicate early ectasia or other structural problems.
Types of abnormal topography
Modern tomography can detect subtle changes that precede visible keratoconus, guiding surgeons away from risky procedures.
- Inferior steepening or skewed bow-tie patterns suggesting early keratoconus
- Asymmetric elevation maps or irregular astigmatism
- High Belin/Ambrosio indices or ectasia scores on Scheimpflug devices
- Marked differences between the two eyes
- Combination with thin corneas or high prescriptions
Next steps when scans are abnormal
Instead of proceeding with LASIK, the focus shifts to protecting the cornea and exploring other ways to correct vision.
- Repeat scans over time to confirm stability or progression
- Cross-linking if progressive ectasia is confirmed
- Contact lenses, ICLs, or lens replacement instead of corneal laser
- Education about avoiding eye rubbing and treating allergies
- Referral to a corneal specialist when uncertainty remains
