“…Complicated rhinosinusitis is defined as the sequelae of direct extension of acute rhinosinusitis to adjacent structures [ 1 , 2 ]. Sequelae of complicated rhinosinusitis include orbital complications, such as preseptal cellulitis, subperiosteal abscess, orbital cellulitis, orbital abscess, and cavernous sinus thrombosis [ [1] , [2] , [3] , [4] ]. Intracranial complications also can occur, resulting in meningitis, epidural abscess, subdural abscess, intracerebral abscess, and osteomyelitis of the frontal bone [ 5 ].…”