Corneal topography is a non-invasive imaging examination that maps the curvature of the front surface of the cornea. It produces colour-coded maps that help the practitioner understand shape, symmetry and areas that are relatively steep or flat.
What does the examination show?
Corneal curvature
The map displays differences in curvature across many measured points rather than providing only one central value.
Shape and symmetry
Patterns can reveal regular or irregular astigmatism and support assessment of unusual corneal shape.
Contact lens planning
Topography supplies valuable information for fitting rigid, specialist and orthokeratology lenses.
Comparison over time
Repeat measurements can be compared when monitoring is clinically indicated.
When may corneal topography be useful?
- Before specialist contact lens or orthokeratology fitting.
- When irregular astigmatism or keratoconus is suspected.
- Before or after certain corneal and refractive procedures, as directed by the ophthalmologist.
- When vision cannot be explained fully by a routine prescription measurement.
What happens during the test?
You look at a fixation target while the instrument captures reflections or other measurements from the cornea. The test is quick and does not touch the eye. Reliable results depend on good fixation, tear-film quality and following any instructions about contact lens removal before the appointment.
Topography and contact lenses
For complex corneal shapes, the map helps guide the first lens design and subsequent adjustments. It does not replace trial fitting and follow-up checks of vision, lens position and eye health.
Do you need a specialist lens assessment?
Explore our contact lens services and arrange an individual suitability assessment.
