Cherry eye occurs when the tear-producing gland swells or protrudes from the lid like a red, fleshy mass. When the gland protrudes, called eversion, the usually moist tissue is exposed to air and other irritations, like a paw. This can cause the interruption of blood supply to the gland.
It seems that there is no way of preventing cherry eye. If caught early, cherry eye may be resolved with a closed-eye massage of the affected eye. However, we do recommend an e-collar so that no further injury is caused to the eye.