What are the reasons for a dog's eye corner growing red nodules?

A dog with red nodules growing on its eye corner is likely suffering from prolapse of the third eyelid. There are many causes for third eyelid prolapse, such as genetic factors, eye diseases, and systemic autonomic nerve abnormalities. Among these, eye diseases are the main cause. With timely treatment, surgery is usually not required.

Several possible causes of third eyelid prolapse or prominence include eye diseases, which are the most common. When a dog's eyes become inflamed, if not treated promptly, the dog will constantly scratch its eyes due to discomfort, exacerbating the inflammation. Combined with the primary cause of inflammation, the third eyelid begins to proliferate and prolapse from the ordinary inflammation. It is best to take the dog to the hospital for examination and treatment when inflammation occurs, and to have the dog wear a head collar daily to prevent scratching.

In addition to eye diseases causing third eyelid prolapse or retraction, genetic factors can also lead to this condition. Dogs with a large eyeball and oversized third eyelid are more susceptible to prolapse due to genetic factors. Since the third eyelid is constantly exposed, it is more prone to damage or stimulation. This specific eye structure can be inherited by future offspring.

Another cause is systemic autonomic nerve abnormalities, which result in decreased sympathetic nerve tension. This condition is most commonly seen in Horner's syndrome and is the least common cause of third eyelid prolapse.