Ocular discharge is a common sign of eye disease. Abnormal discharge may develop suddenly or gradually. The discharge may be watery, mucoid (gray, ropy), mucopurulent (yellow-green, thickened) or bloody. In general, the more discharge present, the more serious the disease.
Causes Obstruction of tear drainage due to abnormal tear ducts or tear duct openings
Excessive production of tears by the tear glands from irritation or inflammation of the surface structures of the eye, or from pain in or around the eye. Examples include:
Keratitis (inflammation of the cornea)
Conjunctivitis
Blepharitis (inflammation of eyelids)
Defects or abnormalities in the eyelids
Corneal ulcers
Glaucoma
Lens luxation (displacement)
Uveitis (inflammation of the iris and blood vessel layers within the eye)
Trauma
Keratoconjunctivitis sicca or dry eye syndrome
Infection on the surface of the eye, or in association with generalized infections or illness
Diagnosis
Certain diagnostic tests are essential to determine the precise cause of the ocular discharge, including:
Complete ophthalmic examination of the eyelids, cornea, conjunctiva, the front and back chambers of the eye
Schirmer tear test
Fluorescein and possible rose bengal staining of the cornea
Tonometry to measure the pressure within the eye
Additional diagnostic tests are required to diagnose some causes of ocular discharge. These may include:
Complete physical examination
Cytology or complete cell analysis of samples collected from the eyelid margins, cornea or conjunctiva
Flushing of the openings where tears drain away from the eye to ensure they are patent (open)
Culture of discharge from the eye to determine the presence of bacterial infections
Complete blood count (CBC) and serum tests to determine the presence of any related systemic problems
Possibly skull X-rays to determine the presence of a problem in the space behind the eye or in the sinuses
Possibly specialized imaging tests such as dacryocystorhinography, an X-ray study of the tear drainage system), computed tomography (CT) scan, and magnetic resonance imaging (MRI)
Treatment
Successful therapy relies on obtaining an accurate diagnosis. Do NOT use human over-the-counter eye drops that are designed to treat red eyes.
Home Care
Gently clean away any eye discharge with a warm moist cloth as needed until the cause of the problem is identified. Do not allow your pet to rub or self-traumatize the eyes.
Do not delay in bringing your pet to your veterinarian for examination as some causes of excessive ocular discharge are potentially vision threatening and require immediate medical attention. Do not administer human prescription eye medicine or even over-the-counter medicines such as Visine® or other topical solutions intended to reduce eye redness to your pet. The underlying cause for the problem must be properly addressed.
As a temporary measure, the eyes may be flushed or the eyelids cleansed with sterile saline solution.
