Scleral lenses

What they are

Unlike standard contact lenses that sit on the cornea, scleral lenses are bigger and rest on the sclera, the white part of the eye. They arch over the cornea, trapping a layer of sterile saline between the lens and the eye. This vault can mask an irregular cornea for sharper vision and bathe the surface in fluid for people with severe dry eye who cannot tolerate ordinary lenses.

Who they help

Scleral lenses are often used when glasses or standard soft lenses cannot give adequate vision or comfort.

• Keratoconus or other corneal irregularity where glasses are not enough
• Severe dry eye, including after surgery or with conditions such as Sjögren syndrome
• Post-corneal transplant or other cases where the corneal surface is uneven

Fitting and daily use

Fitting takes several visits with a contact lens specialist who maps the eye and orders a custom lens.

• Corneal imaging to design a lens that vaults safely over the cornea
• Practice inserting and removing the lens with a plunger or fingers
• Filling the bowl of the lens with saline before placing it on the eye
• Daily cleaning and storage with solutions recommended by your fitter

What to expect

Vision is often much clearer and more stable than with glasses in keratoconus, and many people with dry eye find comfort improves dramatically. Adaptation can take time, and lenses need replacing periodically as the eye or prescription changes. Poor hygiene raises the risk of infection, so follow your fitter's care instructions closely.