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.
