Both PC and OC can present with unilateral ocular erythema, edema, warmth, and tenderness . Fever and other systemic signs may also be seen. Other symptoms specific to OC, related to its invasiveness and potential to increase intraorbital pressure, include chemosis, blurred vision, impaired ocular movements, and proptosis. In general, markers for an inflammatory response are more robust in OC, manifested as higher fevers, greater elvation of C-reactive protein, and a more dramatic left shift