Pachymetry is the measurement of corneal thickness, usually at the centre of the cornea. It is important in refractive surgery planning and in interpreting intraocular pressure in glaucoma.
Measurement and relevance
Ultrasound probes and optical devices can both be used to obtain thickness values. Thin corneas reduce the safety margin for corneal reshaping and are associated with a higher risk of post-operative ectasia.
- Pachymetry helps determine suitability for LASIK, PRK and other procedures
- Very thin or thick corneas can lead to under- or overestimation of IOP
- Serial measurements are useful in monitoring corneal oedema
- Results are interpreted alongside topography and refraction
