Dr Moïse Tourabaly · Cornea

Keratoconus: the cornea bulges into a cone

Cross-section of a normal cornea, deformed into a cone, then strengthened by cross-linking, with a preview of vision. On the left, a cross-section of the cornea in profile. When normal, its curvature is regular. In keratoconus, it thins and bulges into a cone, mainly towards the bottom, along one axis. Cross-linking strengthens the collagen and stabilises the cornea. On the right, a preview of vision goes from a sharp image to a doubled image with halos, then stabilises. Cross-section of the cornea Preview of vision cone axis A sharp image A A doubled image, halos A A stabilised vision

Normal cornea: its curvature is regular and the image forms sharply.

Keratoconus: the cornea thins and bulges into a cone. Vision becomes blurred and doubled, with halos.

Cross-linking: a treatment strengthens the collagen of the cornea (CXL) to stabilise its deformation.

Diagram for educational purposes. It does not replace an ophthalmological examination. Results vary from one patient to another.