67-year-old male with a past medical history of lung cancer and chronic sinusitis presents to the emergency room with left-sided eye pain. He also reports a moderate headache, for which he has taken ibuprofen without relief. On exam, he is noted to have left-sided proptosis (Figure A) and decreased occular range of motion. An MRI is performed, and he is found to have a cavernous sinus thrombosis (Figure B). Which of the following group of nerves run through the cavernous sinus?
1. III, IV, V-1, V-2, and VI
2. III, IV, V-2, V-3, and VI
3. IV, V-1, V-3, VI, and IX
4. V-1, V-2, V-3, VII, and VIII
5. VII, VIII, IX, XI, and XII
Figure A: shows a presentation of severe cavernous sinus thrombosis, with noted proptosis.
Figure B: shows an MRI of a 65-year-old woman presenting with double vision and retro-orbital pain, found to have a cavernous sinus thrombosis
CORRECT ANSWER: 1. III, IV, V-1, V-2, and VI
DISCUSSION: The cavernous sinus contains cranial nerves III, IV, V-1, V-2, and VI. The internal carotid artery also runs through this space.
Cavernous sinus thrombosis occurs when a clot forms in the cavernous sinus, which is a space in the skull in which blood drains from the brain towards the heart. Common symptoms of cavernous sinus thrombosis include proptosis, headache, and decreased ocular range of motion due to impingement of cranial nerves III, IV, and VI. Risk factors for developing a cavernous sinus thrombosis include hypercoagulability, as well as sinus, dental, ear, and nasal infections. S. auerus, and S. pneumococcus are the most common causal organisms, although sometimes no organism is identified. The mainstay of treatment is antibiotics, with or without surgical drainage.
Fiore et. al, discuss the differential diagnosis of pain in the non-red eye. They mention several intracranial processes, including cavernous sinus thrombosis, as well as acute angle-closure glaucoma and giant cell arteritis. They note that cavernous sinus thrombosis typically presents with "rapid onset of unilateral periorbital swelling, photophobia, chemosis [swollen conjunctiva], proptosis, headache, or cranial nerve palsies." The infection often spreads to the contralateral eye within 48 hours.
Desa and Green discuss current recommendations for treatment of cavernous sinus thromboses. They recommend urgent, surgical drainage, as well as a broad-spectrum antibiotic regimen that includes a cephalosporin, nafcillin, and metronidazole, until cultures and sensitivities are returned. The use of steroids was found to be harmful, and the use of anticoagulation is still under debate.
http://www.medbullets.com/step1-neurology/13069/cavernous-sinuses
