Keratonconus: New Technology Available
Keratoconus is a non-inflammatory eye condition in which the normally round dome-shaped cornea progressively thins causing a cone-like bulge to develop. This results in significant visual impairment. Eyeglasses or soft contact lenses may be used to correct the mild nearsightedness and astigmatism caused in the early stages of keratoconus. As the disorder progresses and the cornea continues to thin and change shape, rigid gas permeable contact lenses are often prescribed to correct vision more adequately. The contact lenses must be carefully fitted, and frequent checkups and lens changes may be needed to achieve and maintain good vision and corneal health. This can sometimes be a frustrating process.
However, new technology has enabled the development of new hybrid contact lenses. One lens design has a gas permeable lens core and a skirt of soft lens material. Another design is called a scleral lens–these are large diameter gas permeable lenses that do not rest on the cornea but on the outlying sclera instead. These lens designs are intended to vault over the central cornea and not rest on the cornea at all. This results in greater comfort and better vision.
New technology is also playing a role in the fitting of these contact lenses, as well as more traditional types of contacts. Ophthalmologists and optometrists have traditionally used a corneal topographer to map the shape of the cornea. It gives information that is very similar to a topographical map for hiking. The topographer is a necessary part of the process of evaluating the shape of the cone, simulating corneal curvature and monitoring progression of the disease. Now doctors have a new tool to add to their arsenal–the Optical Coherence Tomographer (OCT). This instrument has been used to generate a cross-sectional image of the layers of the retina similar to the image of an MRI. Due to improved technology, the OCT can also be used to image the the cornea with the contact lens in place. This will be a great help in assessing where the lens rests on the eye and whether or not the vault of the lens is adequate for corneal health. This will help with even the most challenging contact lens fittings and give those with keratoconus better vision and greater comfort.