How ortho-K works: fluid, not force
The tear film does the reshaping, which is why healthy tears matter.
The tear film does the reshaping
Part 01 · 01A thin tear layer in the centre
The lens sits very close to the central cornea. The thin film of tears there creates gentle positive pressure.
A tear reservoir around it
A deeper ring of tears under the lens’s reverse curve creates slight negative pressure, a gentle suction.
The surface cells redistribute
Cells in the outer skin of the cornea shift from the centre toward the mid-periphery. The lens isn’t pressing the eye into shape.
What changes, and what doesn’t
Part 01 · 02Only the outermost layer
The changes happen in the epithelium, the cornea’s thin outer skin, and are measured in microns.
Fully reversible
Stop wearing the lenses and the cornea returns to its original shape, usually over days to a few weeks.
Nightly wear keeps it going
The effect lasts through the day and fades if lenses are skipped.
Why dry eye matters in ortho-K
Part 01 · 03Poor tears weaken the forces
A thin or unstable tear film gives less even pressure, so treatment can be patchy or off-centre.
More binding and staining
Dry eyes raise the chance of a lens sticking overnight and of surface staining in the morning.
We assess and treat first
We check the tear film and oil glands before fitting, and keep managing them alongside ortho-K.
Simple habits help
Lubricating drops before insertion, and again before removal in the morning, keep the lens moving freely.
In summary
Part 01- 01Ortho-K works through tear film pressure, not by squeezing the eye.
- 02Only the cornea’s outer layer changes, and it’s reversible.
- 03Healthy tears give a more even, more comfortable result.
Book an ortho-K assessment.
We map your cornea first, then design the lens around it.
General information only, not personal advice. Suitability for ortho-K is decided after a full eye examination and corneal mapping.