Senior Report 6.23

Case Presentation by Dr. Deshon Moore

A 40 year old man, smoker with no past co-morbids presented to DRH with left facial swelling, sudden loss of vision, HA, and nausea. Symptoms started 10 days prior with mild headache and otalgia. There was no history of trauma. He was treated with analgesics but symptoms worsened. No prior history of otitis media or sinusitis could be elicited. You see him in mod 2 and notice a well built man with obvious swelling of left face, severe proptosis and chemosis of left eye, left mastoid swelling and left complete ophthalmoplegia. He also had a low-grade fever. Visual Acuity was diminished. The pt had little perception of light with relative afferent pupillary defect.

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1) What is the best imaging modality to confirm this diagnosis?

a) CT scan w/o contrast

b) X-ray orbit

c) CT scan w contrast

d) MRI

e) Cerebral angiography

2) Which cranial nerve deficit would be the first expected with this condition?

a) CN VIII & X

b) CN VI only

c) CN VII

d) CN, III,IV, V & VI

e) All of the above

3) What antibiotic regimen would you use for coverage?

a) Erythromycin ophthalmic

b) Clindamycin and vancomycin

c) Vancomycin, Cefotaxime & Flagyl

d) Gentamycin Ophthalmic

e) Ceftriaxone & Flagyl

f) No abx needed

Answers & Discussion:

Cavernous sinus thrombosis (CST) is life threatening but thankfully rare disorder that can affect a person at any age.

This condition happens when a blot clot blocks a vein that runs through a hollow space located underneath the brain and behind the eye sockets. The cavernous sinuses are the most centrally located of the dural sinuses and lie on either side of the sella turcica. These sinuses are just lateral and superior to the sphenoid sinus and are immediately posterior to the optic chiasm.  There is a picture below to depict this. This venous system carries blood from the face and head back to the heart. CST is usually caused by an infection that spreads from the face, teeth or sinuses. It can happen from ear or eye infections but less commonly. Studies show that 25% of the time CST was a result of a furuncle that was either removed surgically or squeezed by a patient and it’s contents spread intracranial. The body creates a blood clot to close off the infection, which creates the CST.

When it happens there is a high mortality rate of about 30-50%. Prompt recognition and treatment is essential.

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There are many symptoms of CST.  Some include severe headache, proptosis, periorbital edema, APD, fever, vision loss, seizures, and chemosis among others. There are mimics of this condition including acute angle glaucoma, subdural hematoma, spinal epidural abscess and others but history and physical should guide you in your diagnosis of CST.

 

1) D

In current practice, computed tomography (CT) scan or magnetic resonance imaging (MRI) with contrast is the modality of choice to confirm the diagnosis of CST and to differentiate it from alternatives such as orbital cellulitis, which may have a similar clinical presentation.

MRI with MR venogram (MRV) is the preferred imaging choice as the MRV will show the absence of venous flow in the affected cavernous sinus.

With non-contrast CT, thrombosis of the cavernous sinus can be appreciated as increased density. The introduction of intravenous contrast can reveal filling defects within the cavernous sinus as well as thickening of the superior ophthalmic vein. Nevertheless, CT scan findings may be subtle, and a negative CT scan cannot rule out CST reliably when the clinical suspicion is high.

Carotid angiography can demonstrate narrowing or obstruction of the inter-cavernous segment of the carotid artery. MRI and CT scan can also show this narrowing and/or obstruction of the carotid artery. Carotid angiography is not ideal in the emergency department as it takes about the same amount of time to get an MRI if not longer and the sensitivity of an MRI is better.

Lab analysis is generally nonspecific but the best supporting labs would be CBC w diff showing leukocytosis w left shift, blood cultures likely showing causative organism and maybe LP which would show inflammatory cells. Fungal cultures would reveal fungal source, which is less likely than bacterial except in diabetics or those with chronic sinusitis. PE and imaging are the primary diagnostic tools of this disease.

2) B

Lateral gaze palsy (isolated cranial nerve VI) is usually seen first since CN VI lies freely within the sinus in contrast to CN III and IV, which lie within the lateral walls of the sinus. Eventually the disease can spread if not treated and one can get contralateral findings. Eventually CN III and IV deficits can happen including mydriasis, ptosis, eye muscle weakness and superior oblique muscle paralysis.

3) C

Staphylococcus aureus accounts for approximately 70% of all infections. Streptococcus pneumoniae, gram-negative bacilli, and anaerobes can also be seen. Fungi are a less common pathogen and may include Aspergillus and Rhizopus species.

Empiric antibiotic therapy should include a penicillinase-resistant penicillin plus a third- or fourth-generation cephalosporin. If dental infection or other anaerobic infection is suspected, an anaerobic coverage should also be added. Recommended treatment is with IV antibiotics for at least 3-4 weeks.

Anticoagulation for cavernous sinus thrombosis is recommended at DRH according to our Neuro Intensivist. There has been controversy over anti-coagulation for this disorder. There are no prospective trials looking at the use of anticoagulation for CST.  This is likely because the condition is so rare. Some retrospective studies have shown a decrease in mortality and clot further clot formation by anticoagulation. A Cochrane review found 2 small trials involving 79 patients who were treated with anticoagulants. Limited evidence suggests anticoagulant drugs are probably safe and may be beneficial for people with sinus thrombosis. Accordingly, we should consider anticoagulation (especially since our Neuro Intensivist recommend it) with heparin since the goal is to prevent further thrombosis and reduce the incidence of septic emboli. Before starting heparin just make sure the patient does not have an intracerebral hemorrhage or other bleeding diathesis.

Corticosteroids may help reduce inflammation and edema and should be considered as an adjunctive therapy.

 

References:

-Duong DK, Leo MM, Mitchell EL. Neuro-ophthalmology. Emerg Med Clin North Am. Feb 2008; 26(1):137-80, vii.

-Karlin RJ, Robinson WA. Septic cavernous sinus thrombosis. Ann Emerg Med. Jun 1984;13(6):449-55

-Rosen’s, Emergency Medicine, 7th edition Volume 2

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