This is one of a number of progressive and degenerative disorders of the cornea (window of the eye) known as dystrophies. A gradual clouding of the cornea occurs which, of course, reduces sharpness of vision.
In this corneal dystrophy, the onset of symptoms is usually in the 6th or 7th decade of life although an eye examination can reveal early changes by the 4th or 5th decades. The disease begins in the posterior layer of the cornea which helps regulate the amount of fluid in the cornea. When this layer with its cells begins to fail, more fluid enters the corneal tissue accounting for the glassy, cloudy appearance and causing scattering of light and cloudy vision. In late stages patients may experience painful erosions of the anterior layer, the epithelium.
There are usually no systemic symptoms but a few patients have reported some hearing impairment. This may simply be an association but since the mutated gene responsible for the corneal disease has also been reported to cause a form of deafness further work will be required to determine the relationship.
This is an autosomal dominant condition in which the disease often passes from parent to child leading to a vertical distribution of affected individuals within a family tree.
The diagnosis is usually made by an ophthalmologist by age 50 or 60 years. The disease gradually progresses and vision becomes more blurred as the cornea becomes cloudier. A corneal transplant is the treatment of choice and provides a good prognosis. The painful erosions on the corneal surface often require patching and the use of drops on the eye.