Twenty patients with orbital cellulitis were treated over a seven-year period. All patients had a CT scan for localization and categorization of the disease. Fourteen of sixteen patients with post-septal involvement underwent surgical drainage and orbital exploration via an external ethmoidectomy approach. Two of these fourteen patients also had an optic nerve decompression. Clinical signs were found to be accurate in differentiating pre-septal from post-septal cellulitis tut were inadequate for further categorization of the type of post-septal cellulitis. All ten patients with pre-septal cellulitis or a post-septal subperiosteal abscess recovered with preservation of vision. Mild to moderate degrees of visual loss could be reversed with emergent surgical treatment even after 10 days from the onset of visual loss. Post-septal intraperiosteal orbital cellulitis and orbital abscess however resulted in significant permanent visual disability in eight of ten cases.