Canine Goniodysgenesis

"Canine goniodysgenesis is one of two primary forms for glaucoma that describe a condition where the fluid in the eye is not draining properly. Immediate treatment is necessary to avoid the onset of glaucoma and vision loss. Options for treatment include medications and surgery."

Glaucoma is common in dogs. There are two forms that are considered primary which means that the condition is directly from a problem in the eye vs. from an illness somewhere else in the body that caused a problem in the eye.

The problem occurs when fluid that is naturally produced in the eye by the ciliary body can't pass through the pupil and out the drainage angle that is located at the front of the eye.

If the holes that allow the fluid to flow is not formed correctly, your dog could be at risk for glaucoma which is a build up of fluid pressure (called IOP or intraocular pressure). The two types of primary glaucoma are:

* Narrow angle glaucoma: abnormal narrow opening into the ciliary cleft)
* Goniodysgenesis: presence of an abnormal pectinate ligament which has teeth like a comb. These "teeth" block the fluid

Draining problems can be inherited. Medical science doesn't quite understand why glaucoma and goniodysgenesis occurs later in life vs. at birth although the obvious answer is that the drainage angle may become narrower with age.


A procedure called a gonioscopy can detect changes in the drainage angle. That combined with techniques for measuring fluid pressure in the eye can help form the basis for a definitive diagnosis.

Breeds With an Above Average Incidence of Canine Glaucoma

Many breeds of dog are affected including:

* Cocker Spaniel
* Basset hound
* Arctic circle breeds (Samoyed, Siberian husky, Norwegian elkhound)
* Bouvier
* Terrier breeds
* Miniature poodle
* Chow chow
* Shar pei

Symptoms of Goniodysgenesis

Symptoms of both forms of primary glaucoma include:

* Severe pain
* Sensitivity to light (photophobia)
* Winking spasms (blepharospasm)
* Eye appears to have fallen into the socket (enophthalmos)
* Raised third eyebrow
* Your dog winces when you touch his or her head
* Watery eyes
* Behavioral Change (hiding, refusal to eat)
* Red Eye
* Dilated Pupils


Your veterinarian will look for the follow signs in addition to the symptoms listed above:

* Fluid buildup in the eye (corneal edema)
* Unresponsiveness to light
* Loss of vision

Treatment of Canine Goniodysgenesis

With immediate treatment of the canine goniodysgenesis and early diagnosis you can avoid vision loss or reverse vision loss.

Several medications are available to help lower the pressure in the eye (intraocular pressure), but some drugs are not effective in all breeds. In this case a combination of medications will be tried.

Surgical techniques that might help are:

* Cyclocryotherapy (freezing tissue)
* Laser therapy
* Creation of drainage pathways

If the eyes are painful, they can be removed via a procedure called enucleation.


Glaucome - The Updates
Simon M Petersen-Jones DVetMed PhD DVOphthal DipECVO MRCVS
Associate Professor
Department of Small Animal Clinical Sciences
College of Veterinary Medicine
D-208 Veterinary Medical Center
Michigan State University
East Lansing, MI 48824


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