Complications of surgical procedures are possible suture erosion through the sclera, conjunctiva, or both. Allergic conjunctivitis is inflammation of the conjunctiva due to allergy. Accessory lacrimal glands in the conjunctiva constantly produce the aqueous portion of tears. A deficiency is described by pathologic dryness of the conjunctiva and cornea. Conjunctivitis is identified by irritation and redness of the conjunctiva. Ethyl acetate is an irritant of the conjunctiva and mucous membrane of the respiratory tract. This includes infections of the eyelids, conjunctiva, and cornea. Bacterial conjunctivitis may cause the production of membranes or pseudomembranes that cover the conjunctiva. Blood to the bulbar conjunctiva is primarily derived from the ophthalmic artery. This substance forms a film that protects the cornea and the conjunctiva from pathogenic organisms. A subconjunctival bleeding initially appears bright-red underneath the transparent conjunctiva. Examination of the eyelid conjunctiva is usually more diagnostic than examination of the scleral conjunctiva. Cherry eye is typically diagnosed by examination of the conjunctiva and nictitating membrane. Occasionally they can even lodge in the conjunctiva under the eyelid. Chemosis is the swelling (or edema) of the conjunctiva.