You can tell at the first glance that the dog's conjunctivitis is inflammation of the dog's conjunctiva. The symptoms may be manifested as inability to open the eyes, tears, and red eyes. Because the conjunctiva is a protective film covered with the eye surface that blocks external stimulation, the first symptoms of the conjunctiva are also caused by external stimulation.
There has always been a saying that the eyes are the window of the soul, and the cornea is the glass of the window. There are many cases of keratitis caused by stimulation of trauma, and there are also complications caused by infectious diseases such as canine distemper. The cornea should be transparent and clear. When keratitis occurs, the dog's cornea will become cloudy, which will also cause pain and tears in the dog's eyes. But the difference from conjunctivitis is that the eyes of dogs should not look so red, and the main symptom is concentrated in the corneal part in the middle of the eyeball.
Introverting the eyelids sounds like a serious disease, but to put it bluntly, it is what we often call "inverted eyelids". The innermost side of the dog's upper eyelid is turned to the inside of the eyes, causing the eyelashes to thorn into the eyes. Many dogs have this problem, and can be solved by having a double eyelid surgery. Eyelid inversion will cause dogs to cry when they are always blinking. If eyelashes irritate their eyes for a long time, they will cause keratitis and conjunctivitis.