Acute orbital inflammation has been induced by injecting bovine serum albumin into the retrobulbar space of rabbits that have been systemically immunized to the same antigen. The principal clinical signs of proptosis, conjunctival chemosis, and lid swelling appear within three hours after injection and are most severe after 24 hours. Signs of anterior chamber reaction, cells and flare, appear as early as two hours after injection.
Histologic changes consist of a polymorphonuclear (PMN) cell infiltration throughout the orbit including muscle, optic nerve sheaths, perivascular and subconjunctival spaces. The optic nerve itself is spared. The choroid and the outer layer of the retina show changes as early as six hours after injection. Maximum reaction of massive PMN cell infiltration occurs by 24 hours after injection.
It is proposed that the widespread inflammation is due to direct diffusion of antigen throughout the orbit and along the vessels into the choroid.
Goodner EK, Aronson SB. Experimental Immunogenic Orbital Inflammation. Arch Ophthalmol. 1974;91(4):303-307. doi:10.1001/archopht.1974.03900060313014