Corneal mapping refers to graphical representations of corneal curvature, elevation, and thickness across the surface, created from topography or tomography data. It provides a detailed picture of corneal shape.
Map Types
Common maps show axial or tangential curvature, anterior and posterior elevation, pachymetry, and refractive power distribution. Colour scales indicate steep and flat areas, making irregularities easy to spot.
- Used to diagnose ectatic disorders such as keratoconus
- Helps plan laser refractive procedures and corneal cross-linking
- Useful in fitting complex contact lenses
- Serial maps track progression or stability over time
Clinical Importance
Detailed mapping allows detection of subtle asymmetries not visible on standard keratometry. It supports risk assessment before surgery and helps explain visual symptoms related to irregular astigmatism.
- Abnormal patterns may contraindicate corneal refractive surgery
- Regional thickness data guide treatment depth decisions
- Postoperative maps assess outcomes and identify complications
- Interpretation requires understanding of normal variation and artefacts
