The first contact lenses used were haptic or scleral lenses. Both terms are used interchangeably. These lenses are about 20 to 25 mm in diameter. They cover the whole cornea and rest of the sclera.
The first scleral lenses were
fluid lenses. The lens vaulted the
cornea with a significant gap
between the cornea and the back
of the lens. The lens was filled
with fluid (usually saline although
many different solutions were
tried) to prevent a bubble from
covering the pupil. The first
haptic lenses used in the early 1900ΓÇÖs were first made of glass and later of a plastic (about 1936).
Fluid lenses caused corneal swelling (edema) because the cornea did not receive sufficient oxygen although at the time the reason was not known. The patientΓÇÖs vision would become cloudy after a few hours of wear.
