Flash Required
     
 
 
 
 
Corneal Dystrophies
     Although there are over twenty different corneal dystrophies, most have these features in common: dystrophies 1) are usually inherited, 2) affect the right and left eyes more or less equally, and 3) are not caused by outside factors such as injury, activity, or diet.  Dystrophies have other similarities: 4) most start gradually and get worse gradually, 5) most usually begin in just one of the five corneal layers and later spread to nearby layers, 6) most are not in any way related to diseases affecting other parts of the eye or the rest of the body, and 7) most can occur in otherwise totally healthy persons of either sex.

   Corneal dystrophies can affect persons of all ages, but each dystrophy has a characteristic time of life when it is first noticed by patients or their ophthalmologists.  For example, the dystrophy keratoconus often affects patients in their teens and 20's; another common dystrophy, called Fuchs' dystrophy, typically is not noticed until patients are in their 50's and 60's.

   Almost all of the corneal dystrophies are inherited in a way that is called autosomal dominant.  Autosomal means that male and female children of a person with a dystrophy are equally at risk of inheriting the dystrophy.  Dominant in this Instance means that It Is likely that one of the patient's parents has the dystrophy and that each and every offspring of the patient has one chance In two of inheriting the dystrophy.  Unfortunately, at present there Is no way of predicting before birth whether or not a child will be affected.

   A few corneal dystrophies have different means of inheritance.  Keratoconus and macular dystrophy are two of these; their means of Inheritance will be explained in the separate books dealing with each of them.

   Often not all family members with the dystrophy have equally severe forms of it.  To give an extreme example, one person with dystrophy might lose useful vision so that he needs a corneal transplant by age 20, whereas his sister who has the dystrophy might see well until she Is In her 30's or 40's.  What controls this variability of severity In a family is not known.

   Corneal dystrophies affect vision in widely differing ways.  A few cause no vision problems at all and are only incidentally discovered during a routine eye examination. 

   Others cause repeated episodes of eye pain without leading to permanent loss of vision; these dystrophies usually affect the epithelium (layer 1) or its basement membrane.  The epithelium does not stick properly to the basement membrane, so that normal actions, such as blinking or s1eeping, can make epithelial cells peel off.  This is called an epithelial abrasion or erosion. (See Fig. 1)  It produces the painful foreign-body sensation that we described In Section 1.  The most common time for patients to get an epithelial erosion in this way is overnight, so that the patient first notices It on awakening in the morning.




   Treatment is readily available for epithelial erosions when they occur; your ophthalmologist will probably treat you with drops, ointment, and/or an eye patch.  (See Fig. 2)  With treatment, these erosions usually heal within 1-3 days.  Unfortunately, in many patients these erosions occur repeatedly; this problem is called recurrent erosion.  In patients with some corneal dystrophies, the erosion can occur quite frequently and can be a problem for many' months or even a few years; in others, the erosions occur infrequently and are much less bothersome.  Recurrent erosions can sometimes be prevented through the use of drops, ointment, or even a soft contact lens.

 

 


   In some other dystrophies, severe loss of vision often occurs from either dense corneal clouding or roughening of the corneal surface.  Some of these dystrophies also cause episodes of foreign-body sensation from recurrent erosions, as we just discussed.  Many patients who have dystrophies in this group will eventually require corneal transplantation in order to see well again. (See Fig. 3.)  Fortunately, corneal transplantation is very often successful for them and enables them to resume full, active lives.

 


 


Visit Us at:

  2068 Palm Beach Lakes Boulevard, West Palm Beach, FL  33409
 
Telephone:  561-684-4773  |  Fax:  561-684-9526
  General Information E-mail: 
Info@Canovision.com

Se habla Español

  Copyright © 1999-2008 by Cano & Manning Eye Center PLLC, All Rights Reserved