Keratoconus is a thinning disorder of the cornea that causes visual distortion. The cornea loses its natural round shape and becomes distorted with cone-like bulging, progressive thinning, and a reduction in vision quality.
Symptoms include ghosting, multiple images, glare, halos, starbursts around lights and blurred vision even with vision correction. The exact cause is unknown, although it is believed that genetics, environment, and hormones play a role.
1. Rigid Gas-Permeable lenses (RGPs) = small-diameter contact lenses made of oxygen permeable rigid materials, they are designed to mask the corneal irregularity and provide better vision.
2. Scleral contacts = large-diameter gas permeable (rigid) contact lenses specially designed to vault over the entire corneal surface and rest on the “white” of the eye (sclera). In doing so, scleral lenses functionally replace the irregular cornea with a perfectly smooth optical surface to correct vision problems caused by keratoconus and other corneal irregularities. Also, the space between the cornea and the back surface of a scleral lens acts as a fluid reservoir to provide comfort for people with severe dry eyes who otherwise could not tolerate contact lens wear.
3. Intacs = Intacs are micro-thin plastic, semi-circular rings inserted into the mid layer of the cornea. When inserted in the keratoconus cornea they flatten the cornea, changing the shape and location of the cone. The placement of Intacs remodels and reinforces the cornea, eliminating some or all of the irregularities caused by keratoconus in order to provide improved vision. Glasses or contact lenses may still be needed for functional vision.
4. Corneal Cross-Linking (CXL) = works by increasing collagen crosslinks which are natural “anchors” within the cornea. These anchors are responsible for preventing the cornea from bulging out and becoming steep and irregular. CXL is not a cure for keratoconus but the aim is to arrest the progression and prevent further deterioration in vision and the need for corneal transplantation. Glasses or contact lenses would still be needed following the treatment.
5. Corneal Transplant = only about 15-20% of those with keratoconus ultimately require corneal transplant surgery. A transplant is warranted when the cornea becomes dangerously thin or when sufficient visual acuity to meet your needs can no longer be achieved by other methods such as contact lenses.