Corneal dystrophy is a group of rare hereditary disorders characterised by bilateral abnormal deposition of substances in the transparent front part of the eye called the cornea. Signs and symptoms
Corneal dystrophy may not significantly affect vision in the early stages. However, it does require proper evaluation and treatment for restoration of optimal vision. Corneal dystrophies usually manifest themselves during the first or second decade but sometimes later. It appears as grayish white lines, circles, or clouding of the cornea. Corneal dystrophy can also have a crystalline appearance.There are over 20 corneal dystrophies that affect all parts of the cornea. These diseases share many traits:
They are usually inherited. They affect the right and left eyes equally. They are not caused by outside factors, such as injury or diet. Most progress gradually. Most usually begin in one of the five corneal layers and may later spread to nearby layers. Most do not affect other parts of the body, nor are they related to diseases affecting other parts of the eye or body. Most can occur in otherwise totally healthy people, male or female.Corneal dystrophies affect vision in widely differing ways. Some cause severe visual impairment, while a few cause no vision problems and are diagnosed during a specialized eye examination by an ophthalmologist. Other dystrophies may cause repeated episodes of pain without leading to permanent loss of vision. Genetics
Different corneal dystrophies are caused by mutations in the CHST6, KRT3, KRT12, PIP5K3, SLC4A11, TACSTD2, TGFBI, and UBIAD1 genes.
Superficial corneal dystrophies do not need a penetrating keratoplasty as the deeper corneal tissue is unaffected, therefore a lamellar keratoplasty may be used instead.Phototherapeutic keratectomy (PTK) can be used to excise or ablate the abnormal corneal tissue. Patients with superficial corneal opacities are suitable candidates for this procedure. See also
Recurrent corneal erosion
Keratoconus
Keratoglobus
Corneal dystrophies in dogs
Dyskeratosis corneal and photophobia in XLPDR


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