Vitreous Degeneration Study

 
 


The vitreous is the largest physical structure in the eyeball.  It is located inside of the eyeball just behind the lens but in front of the retina.  It is a firm jelly like structure and crystal clear.  All of the light that enters the eye to be shown on the retina must first pass through the vitreous.  Over time there is a normal age related degradation of this structure that changes its physical character.  This change is called degeneration.  Degeneration of the vitreous humor of the eye is a normal aging change in all dogs and normally does not progress to any significant degree (doesn't cause a problem); however there appears to be an over-representation and increased degree of severity of this condition in the Whippet and Italian Greyhound breeds based upon data from CERF (Canine Eye Registry Foundation). There is no detailed information about the clinical course or possibly heritable nature of this problem at this time in the dog.

The actual change is one that results in the vitreous to become more fluid in consistency and cloudy.  These physical changes have a potential to lead to serious sight threatening consequences.  Movement of the vitreous into the anterior chamber could block the outflow of aqueous humor fluid and lead to glaucoma.  The change of the vitreous to a more fluid state could result in lens movement and subsequent lens luxation as well as retinal detachment.

Therefore the specific GOALS of this project are:

•Determine the incidence and age of occurrence of vitreous degeneration in the Whippet and Italian Greyhound.

•Characterize how vitreous degeneration changes over time by examining all ages of animals starting at 8 weeks of age and continuing to examine each animal yearly for its full life.

•Look for any negative consequences of vitreous degeneration over time and characterize the severity.

•Identify characteristics of the condition that predict the advent of serious complications.

Investigate and characterize familial relationships of affected animals.

•Consider possible therapeutic options.

  1. Use the initial AKC 3 year grant and subsequent examination findings as a spring board for securing additional funds to carry the study out capturing the full-life of some of the animals examined.


And the specific Tasks of this project are:

•Enroll as many individual animals as possible.

•Enroll all parents and offspring of these animals.

•Examine all of these animals once each year for their life time according to a specific protocol.

•Look at Familial Association of all of those affected with Vitreous Degeneration.

•Analysis of data to determine outcome or consequences of having vitreous degeneration.

•This knowledge will then help determine strategies not only for breeding but for therapeutic interventions.

Current # of Whippets entered in Database

642

Current # of Whippet Eye Exams

550

Current # of Whippets Examined

417

Current # of Italian Greyhounds entered in Database

60

Current # of Italian Greyhound Eye Exams

43

Current # of Italian Greyhounds Examined

40

Current % of Whippets Affected with VD

16.6%

Current % of Italian Greyhounds Affected with VD

51%

 

 What is Vitreous Degeneration and What are the Goals of this Study?

Please down load one copy of each of the two study forms before coming for the examination. Please fill out the forms (excluding the examiner’s portion of course) before coming to the clinic since you will need to research the familial background to complete the forms.

CLICK EACH TO DOWNLOAD FORMS: DATA-2.pdf, FAMILY-F.pdf