Corneal dystrophies

Corneal dystrophies are abnormal developments affecting the cornea of the eye.

The clearness (transparency) of the cornea is affected, though without necessarily any inflammation, infection, or other eye disease being present in the same eye. Vision through the affected eye may or may not be affected.

Corneal dystrophies are quite rare eye conditions that usually occur early in life (by the time a person reaches his or her twenties). The first cause considered is genetic, that is inherited, passed-on through familes.

There are many types of corneal dystrophy. They are described in different ways, in some cases referring to the particular layer of the cornea that is affected.

Types of corneal dystrophy include epithelial dystrophies and stromal dystrophies. Specific examples include :

• Epithelial basement membrane dystrophy - which is the most common epithelial dystrophy.
• Meesman's dystrophy - very rare, usually affects both eyes equally, may be diagnosed in infancy without symptoms developing until early adulthood or later. (Cause unknown.)
• Reis-Bücklers dystrophy - affects both eyes equally. Symptoms include light sensitivity and 'foreign body' sensations. Vision is adversely affected by the surface of the cornea becoming hazy and irregular.
• Thiel-Behnke dystrophy - is rare and usually diagnosed in childhood when individual crumb-like granules can be seen in the anterior stroma.
• Lattice dystrophies - initial symptoms include 'foreign body' sensations and mild deterioration in vision. When viewed using a microscope, very fine lines can be seen in the cornea.
• Granular dystrophy - vision does not deteriorate initially grey-ish dots on the cornea are visible through a microscope. Slowly, the dots become larger and more numerous. Eventually they become visible to the naked eye.
• Fuchs' endothelial dystrophy - generally occurs (sometimes intermittently) later in life, when small whitish spots may be seen on the inner surface of the cornea.