Symptoms of Dog Nasal Duct Obstruction: What to Look Ou

Symptoms of Dog Nasolacrimal Duct Obstruction:

The eyes exhibit a persistent discharge of pus at the inner canthus, accompanied by a constant flow of tears. The fur beneath the eye corners appears red due to prolonged exposure to tears, leading to some hair loss in the area. Despite these symptoms, the affected dog does not show signs of pain, and there is no noticeable decline in vision or symptoms like photophobia or cloudy eyes.

Causes:

Congenital: This condition can be caused by congenital narrowing or displacement of the nasolacrimal duct, as well as the presence of conjunctival folds covering the duct, lacrimal duct atresia, or eyelid abnormalities such as entropion.

Acquired: It is often associated with conjunctivitis, dacryocystitis, and trauma. Upper respiratory infections and dental issues with the maxilla can lead to secondary inflammation of the nasolacrimal duct. Chronic inflammation can stimulate the swelling of lacrimal duct epithelial cells, tissue proliferation, and scar formation, resulting in narrowing or obstruction of the duct.

Differential Diagnosis:

Congenital nasolacrimal duct anomalies typically appear in puppies a few weeks to several months after weaning, affecting one or both eyes. There may be staining and a persistent presence of puslike discharge in the eye corners without pain or photophobia. In cases of dacryocystitisinduced obstruction, in addition to the overflow of tears, the dog may exhibit pain, swelling, and inflammatory discharge. Severe cases can show symptoms of purulent conjunctivitis or eyelid abscesses.

Treatment:

First, the dog is anesthetized using a general anesthetic. A dose of 0.5mL of Xianshenxin, administered intramuscularly at a rate of 0.1mL/kg body weight, is used. The dog is then placed on its side with the affected eye facing upwards. Locate the lacrimal punctum on the thicker part of the upper eyelid, approximately 25mm from the canthus, and insert a nasolacrimal duct irrigation needle along the nasal direction. Upon reaching about 1cm depth, attach an syringe filled with a premixed 1% procaine penicillin solution and flush repeatedly. The procedure should be gentle to avoid rough handling. Continue until resistance decreases and fluid slowly starts to drain from the nostril on the affected side, transitioning from a dotlike to a linear flow. This indicates that the nasolacrimal duct is clear and the irrigation is successful. Afterward, the dog is placed in a contact restraint and administered 0.5mL of a wakeup drug intravenously.

Given the delicate nature of the dog's nasolacrimal duct, the irrigation process must be done with extreme care to prevent rupture. The incidence of this condition is higher during autumn and winter. The increased rainfall and humidity in autumn, along with the proliferation of mosquitoes and flies, can lead to infections. In winter, the dry climate and abundant dust and sand can also trigger the disease. Therefore, it is crucial to maintain good hygiene for both the dog and its environment to prevent this condition.