Medial Canthal Pocket Syndrome in Dogs: Causes, Symptoms & Treatment

Medial Canthal Pocket Syndrome (MCPS) is an ocular condition in dogs caused by an abnormality in the eyelid structure, particularly around the medial canthus – the inner corner of the eye. This anomaly creates a conjunctival pocket where dirt and debris accumulate, causing chronic irritation and inflammation of the cornea and conjunctiva.

Breeds Most at Risk of Developing Medial Canthal Pocket Syndrome

MCPS primarily affects brachycephalic breeds with their distinctive facial shape and deep-set eyes. However, it also occurs in dogs with shallow eye orbits or large orbits relative to eye size, such as the Afghan Hound. These physical traits lead to debris being trapped in the conjunctival pocket, causing persistent irritation.

Breeds especially prone to MCPS include:

• Dobermann puppies
• Standard Poodle puppies
• Afghan Hound puppies
• Rough Collie puppies
• Lurchers
• Weimaraner puppies
• Golden Retriever puppies
• Labrador retriever puppies
• Great Dane puppies
• Rottweiler puppies

Symptoms Associated with Medial Canthal Pocket Syndrome

MCPS often goes unnoticed as the symptoms can be mild initially. Common signs include chronic conjunctivitis caused by the accumulation of debris in the conjunctival pocket. Dogs may have watery or thick, sticky discharge and swollen or weepy eyes, especially noticeable in the morning.

Affected dogs often rub their eyes upon waking, which can worsen irritation, leading to soreness and redness in the eyes. Although discomfort may appear limited, ongoing inflammation may increase the risk of painful secondary eye conditions, such as corneal ulcers or pigmentary keratitis.

When Does a Dog Start To Show Symptoms?

Dogs typically present symptoms of MCPS between 6 and 18 months of age. Owners may notice persistent eye discharge that does not seem to distress the dog greatly but requires regular cleaning to maintain eye hygiene.

Diagnosing Medial Canthal Pocket Syndrome

A veterinary examination focuses on observation of the eye structure, conjunctival pocket, and presence of debris. Additional tests may include:

• Neurological tests to rule out other causes of eye discomfort
• Schirmer tear test to assess tear production
• Swab tests of eye discharge for bacterial culture and sensitivity

Treatment Options for MCPS

In mild cases, treatment may not be necessary beyond regular cleaning and monitoring. For more severe cases, topical medications such as anti-inflammatories and antibiotics may be prescribed to control infection and inflammation.

Flushing of the nasolacrimal ducts under topical anaesthesia or sedation may be performed to clear blockages. In advanced or refractory cases, surgical correction by medial canthoplasty (blepharoplasty) may be recommended. This procedure shortens the eyelid fissure, eliminating the conjunctival pocket and improving eye comfort and health.

Prognosis

With appropriate veterinary care, including surgery when indicated, dogs with MCPS can experience significant improvement in eye comfort and reduced risk of secondary complications. Early diagnosis and ongoing management are key to maintaining quality of life and ocular health.