Corneal topography and pachymetry
corneal topography · pachymetry · cornea map · corneal thickness test
A machine takes pictures of the cornea, the clear front part of the eye. It shows its shape and thickness.
Before laser vision correction, when fitting contact lenses, and when keratoconus is suspected or followed.
⏱ Duration: usually 5 to 15 minutes; results right away
Be sure to tell your doctor
How to prepare
- Contact lenses. Soft lenses are usually stopped a few days before, hard lenses longer. The clinic will tell you exactly.
- Makeup. Come without mascara or eye shadow.
What to bring
- Your ID
- Your glasses
- Past test results
How it goes
- You sit at the machine and rest your chin on the stand
- You look at a light
- The machine takes pictures of each eye
- Sometimes thickness is measured with a small probe after eye drops
- The doctor looks at the maps and explains the result
What you'll feel
- It does not hurt
- The light is bright, and you need to keep from blinking for a few seconds
- If a probe is used, numbing drops are put in first
Afterwards
- You can go back to your normal day right away
- If you had drops, do not rub your eyes for 20 to 30 minutes
- The doctor will discuss the result right away or at your visit
Common questions
Why stop wearing contact lenses beforehand?
Lenses change the shape of the cornea, and the result will not be accurate.
Can I drive right after?
Usually yes. If you had drops, ask the doctor.