Keratoconus treatments

Friday, November 20th, 2009 at 1:19 pm Post in Eye Diseases

Patients with keratoconus always have a cone-like cornea, which deflects light on its way to retina. In one or both eyes, keratoconus may cause vision distortion.

As a progressive eye disease, keratoconus develops slowly. Since the cornea is always thinning, nearsightedness and irregular astigmatism may develop at certain stages of keratoconus, bringing distorted and blurry vision. Other symptoms of keratoconus include glare, light sensitivity and changing prescription.

Weakening and bulging cornea is always caused by an imbalance of enzymes within it. So that people with keratoconus are more susceptible to oxidative damage from compounds called free radicals. Oxidative damage also comes from a generic predisposition, overexposure to UV rays, excessive eye rubbing, chronic eye irritation etc…

Treatments for keratoconus vary from eyeglasses to corneal transplant, depending on the degree of corneal irregularity. In the slightest form of keratoconus, ordinary eyeglasses or soft contact lenses are enough.

Gas permeable contact lenses can deal with keratoconus that is beyond soft lenses. Their rigid lens material is more competent to replace the irregular corneal shape. Disadvantages of RGPs are clear, such as discomfort, challenging and time-consuming fitting.

A wise way to resolve those disadvantages of RGPs is to use the technology of “piggybacking”. This treatment involves two types of contact lenses: a soft lens directly on the cornea and another GP lens over the soft one. The soft lens performs as a cushioning pad and provides more comfort. It is important to take use of lenses with good oxygen permeability.

Hybrid contact lens uses a soft peripheral “skirt” on a highly oxygen permeable GP lens. With a variety of parameters, these contact lenses offer clear vision from GP lens and comfort from soft lens.

Patients with abnormal functional vision may need intacs or corneal inserts to reshape their corneas. Approved in 2004, these tiny plastic inserts are placed under the eye’s surface in the corneal periphery. Intacs have been reported to improve visual acuity by two lines on a standard eye chart. However, these devices can only delay the progression of keratoconus.

Approved in 1994, Boston Scleral lens Prosthetic Device (PSLPD) contact the eye’s sclera, rather than resting over the cornea. PSLPD maintains a “pool” of fluid on the eye’s surface to help the light focus. The non-profit Boston Foundation for Sight also provides subsidies to low-income patients.

A non-invasive procedure named C3-R places eye drops containing riboflavin on the cornea, which will be activated by UV light so as to enhance corneal tissue links. This procedure for keratoconus has been proved to be promising and is estimated to reduce the need for corneal transplant.

Patients with serious keratoconus that is beyond all of the above treatments can resort to a corneal transplant. Also called penetrating keratoplasty, this last remedy replaces your irregular cornea with another healthy cornea.