Contact lens fitting in keratoconus.

VISSUM/ Instituto Oftalmologico de Alicante, Alicante, Spain.
Comprehensive ophthalmology update 7(2):47-52.
Source: PubMed

ABSTRACT The treatment of keratoconus can be implemented by the use of spectacle lenses, contact lenses of various kinds, and surgery. In this article, we deal with the procedures of contact lens fitting in patients diagnosed with keratoconus. The different types of specific contact lenses and the methodology of fitting these contact lenses for keratoconus are described. To select a contact lens for the individual patient depends upon the severity of keratoconus and the amount of corneal ectasia. Pending these criteria, a contact lens is chosen, which will give the best visual acuity and tolerance. At present, many designs of special contact lenses exist in oxygen-permeable materials; in addition, other systems, such as piggy-back, SoftPerm, semi-scleral, and scleral contact lens types are used. Contact lens fitting on a conical cornea will smooth out the highly irregular optical surface of the cornea and improve visual acuity considerably. Contact lenses are one of the better solutions to correct refractive errors induced by pathology, and they should be prescribed as soon as the keratoconus is detected to avoid development of amblyopia. The quality and quantity of vision is far better than with spectacle lens correction.

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