Keratoconus is a degenerative ailment of the eye caused due to structural changes within the cornea from a normal gradual curve to a more conical shape. The Keratoconus contact lenses are the soft or rigid contact lenses to be worn over the eye when the patient is affected with the eye disorder Keratoconus. The rigid Keratoconus contact lenses improves vision by filling the gap between smooth regular inner surface of lens and irregular corneal surface with tear fluid.
The soft hydrophilic keratoconus contact lenses mostly silicon hydro gel lenses may attune to the conical shape of cornea and hence not used much. To overcome this problem the hybrid Keratoconus contact lenses are encompassed by a delicate skirt and are hard in the centre has been developed. Scleral lenses is also a type of Keratoconus contact lenses prescribed for irregular and advanced conditions, as these cover a greater portion of the eye enhancing stability. Some of Keratoconus contact lenses known as mini sclerals have the features of both scleral lenses and hard or rigid contact lenses which is vaulted over the cornea in the limbus region.
- Use of Keratoconus Contact lenses:
In early stages of Keratoconus, the soft keratoconus contact lenses can suffice to correct the mild astigmatism. However, as the condition progresses, the soft Keratoconus contact lenses may no longer provide adequate degree of visual activity and hence the hard rigid keratoconus contact lenses are used. These rigid contact lenses are known as RGP or rigid gas permeable lenses. The rigid gas permeable lenses provide good level of visual correction, but cannot arrest the progression of the disorder. The mini scleral keratoconus contact lenses so far the most comfortable contact lenses as they are light in weight with easy maintenance and high oxygen permeability. The piggy back Keratoconus contact lenses are used occasionally to correct Keratoconus.