Synechiae

Adhesions of the Iris of the Eye in Cats

Synechiae are adhesions between the iris and other structures in the eye. They are the result of inflammation in the iris and are particularly common with anterior uveitis (inflammation of the dark tissues of the eye) and trauma to the eye. Synechiae can occur in both dogs and cats.

Symptoms and Types

Synechiae may be anterior or posterior.

Anterior synechiae is defined as an adhesion between the iris and the cornea. The cornea is the transparent cover of the front of the eye.

Posterior synechiae is the adherence of the iris to the capsule surrounding the lens of the eye.

Symptoms seen with synechiae include:

Squinting

Corneal lesions, such as ulcers

Excessive tearing

Glaucoma

Variation in the color of the iris

Opacity of the lens

Uveitis

Decreased papillary reaction to light

Causes

Cat fight injury

Chronic infection

Corneal ulcer

Foreign body injury to the eye

Hyphema (bleeding in the front part of the eye)

Penetrating wounds to the eye

Surgery

Diagnosis
Diagnosis is based on an ophthalmic examination, which involves examining the structures of the eye. In addition, dyes may be used on the cornea to detect corneal injuries. Tonometry may be performed to measure the intraocular pressure (the pressure within the eyeball.)

Treatment
In many cases, no treatment is necessary. If an underlying cause is diagnosed, it should be treated appropriately. In cases where glaucoma is present, laser surgery to repair the synechiae may be attempted.