Editing Sinusitis (section)

==== Orbital complications ====
The Chandler Classification is used to group orbital complications into five stages according to their severity.<ref>{{cite journal|vauthors=Chandler JR, Langenbrunner DJ, Stevens ER|date=September 1970|title=The pathogenesis of orbital complications in acute sinusitis|journal=The Laryngoscope|volume=80|issue=9|pages=1414–28|doi=10.1288/00005537-197009000-00007|pmid=5470225|s2cid=32773653}}</ref> Stage I, known as preseptal cellulitis, occurs when an infection develops in front of the [[orbital septum]].<ref name=":1">{{Citation|last1=Bae|first1=Crystal|title=Periorbital Cellulitis|date=2024|work=StatPearls|url=https://www.ncbi.nlm.nih.gov/books/NBK470408/|access-date=2024-11-13|place=Treasure Island (FL)|publisher=StatPearls Publishing|pmid=29261970|last2=Bourget|first2=Daniele}}</ref> It is thought to result from restricted [[Venous|venous drainage]] from the sinuses and affects the soft tissue of the eyelids and other superficial structures.<ref name=":1"/> Stage II, known as orbital cellulitis, occurs when infection develops behind the orbital septum and affects the [[Orbit (anatomy)|orbits]].<ref name=":1"/> This can result in [[Ophthalmoparesis|impaired eye movement]], [[Exophthalmos|protrusion of the eye]], and [[Chemosis|eye swelling]].<ref name=":1"/> Stage III, known as subperiosteal abscess, occurs when [[pus]] collects between walls of the orbit and the surrounding periosteal structures.<ref name=":1"/> This can result in impaired eye movement and acuity.<ref name=":1"/> Stage IV, known as orbital abscess, occurs when an abscess forms within the orbital tissue.<ref name=":1"/> This can result in severe vision impairment.<ref name=":1"/> Stage V, known as cavernous sinus thrombosis, is considered an intracranial complication. It can occur as bacterial spread progresses, triggering blood clots that become trapped within the cavernous sinus.<ref>{{Citation|last1=Plewa|first1=Michael C.|title=Cavernous Sinus Thrombosis|date=2024 |work=StatPearls|url=https://pubmed.ncbi.nlm.nih.gov/28846357/|access-date=2024-11-13|place=Treasure Island (FL) |publisher=StatPearls Publishing|pmid=28846357|last2=Tadi|first2=Prasanna|last3=Gupta|first3=Mohit}}</ref> This can result in previously described symptoms within the opposite eye and in severe cases, meningitis.<ref name=":1"/>