The formation of large blisters inside the eyeballs is usually considered to be caused by conjunctival lymphocysts or conjunctival edema. 1. Conjunctival lymphocysts: patients of any age may develop the disease, which will form relatively small cysts at the beginning, and with the gradual stagnation of lymphatic fluid, the size of the cysts will gradually increase, and even form multiple cysts. Surgery is usually needed to remove them to eliminate the symptoms. 2. Conjunctival edema: usually due to inflammatory stimulation, rubbing the eyes, allergies and other factors, and may be accompanied by conjunctival congestion, you can use cold compresses to promote the edema to subside, but at the same time should also be actively treating the cause of the edema of the original disease, to avoid the formation of edema again. When large blisters appear in the eyeballs and are accompanied by discomfort, it is recommended to consult a doctor for examination to clarify the cause, and treat the blisters under the doctor’s guidance, and do not squeeze or rub on your own.