A<unk> , also known as a<unk>  contact<unk> , is a large contact<unk>  that rests on the<unk> and creates a tear-filled vault over the cornea.<unk> es are designed to treat a variety of eye conditions, many of which do not respond to other forms of treatment.
Scleral lens
Corneal button
Optic cup 
Intraocular lens
Optic pit
Corneal limbus
Optic vesicle
Lacrimal sac