Lattice dystrophy type I is one of the more common hereditary disorders of the cornea and occurs throughout the world. Unlike type II, it does not seem to affect the rest of the body tissues and the main clinical problem is that of reduced vision.
The cornea (clear windshield of the eye) seems to be the only tissue affected. Little strings of opacities resembling cotton threads appear in the cornea beginning in childhood. Sometimes the cornea develops surface defects that are painful like a scratched cornea. This is a progressive disorder and the corneal clouding steadily increases and vision becomes more blurred. Some individuals benefit from a corneal transplant in their 40s and 50s although the deposits in the cornea tend to recur over a long period of time.
This type of corneal degeneration is inherited in an autosomal dominant pattern and parents can directly pass it on to their children.
The cloudiness of the cornea can be seen by direct inspection but an eye professional is required to make the proper diagnosis as it superficially resembles other forms of corneal disease. Prognosis varies from one individual to another but generally vision remains normal or near normal throughout life. In some people, however, the cloudiness significantly interferes with vision in midlife and a corneal transplant is necessary to restore good vision.