Scleral lenses are designed to treat a variety of eye conditions, many of which do not respond to other forms of treatment.

Scleral lenses may be used to improve vision and reduce pain and light sensitivity for people with a growing number of disorders or injuries to the eye, such as severe dry eye syndrome, microphthalmia, keratoconus,[1] corneal ectasia, Stevens–Johnson syndrome, Sjögren's syndrome,[2] aniridia, neurotrophic keratitis (anesthetic corneas), complications post-LASIK, higher-order aberrations of the eye, complications post-corneal transplant and pellucid degeneration.

[3] Sclerals may also be used in people with eyes that are too sensitive for other smaller corneal-type lenses, but require a more rigid lens for vision correction conditions such as astigmatism.

[4] A variant of scleral lenses that do not use reservoirs are commonplace as practical effects in films and television shows, and are used as part of costume design to represent characters with unusually-coloured eyes.

The liquid, which is contained in a thin elastic reservoir, conforms to the irregularities of the deformed cornea, allowing vision to be restored comfortably.

Unlike regular contact lenses, many sclerals can be stored dry when unused for longer periods of time.