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Cavernous sinus thrombosis

Cavernous sinus thrombosis is a blood clot in an area at the base of the brain.


The cavernous sinus receives blood from veins of the face and brain. The blood drains it into other blood vessels that carry it back to the heart. This area also contains nerves that control vision and eye movements.

Cavernous sinus thrombosis is most often caused by a bacterial infection that has spread from the sinuses, teeth, ears, eyes, nose, or skin of the face.

You are more likely to get this condition if you have an increased risk of blood clots.


Symptoms include:

  • Bulging eyeball, usually on one side of face
  • Cannot move the eye in a particular direction
  • Drooping eyelids
  • Headaches
  • Vision loss

Exams and Tests

Tests that may be ordered include:

  • CT scan of the head
  • Magnetic resonance imaging (MRI) of the brain
  • Magnetic resonance venogram
  • Sinus x-ray


Cavernous sinus thrombosis is treated with high-dose antibiotics given through a vein (IV).

Sometimes surgery is needed to drain the infection.

Outlook (Prognosis)

Cavernous sinus thrombosis can be deadly if left untreated.

When to Contact a Medical Professional

Call your health care provider right away if you have:

  • Bulging of your eyes
  • Drooping eyelids
  • Eye pain
  • Inability to move your eye in any particular direction
  • Vision loss



Durand ML. Periocular infections. In: Bennett JE, Dolin R, Blaser MJ, eds. Mandell, Douglas, and Bennett's Principles and Practice of Infectious Diseases. 8th ed. Philadelphia, PA: Elsevier Saunders; 2015:chap 118.

Nath A, Berger J. Brain abscess and parameningeal infection. In: Goldman L, Schafer AI, eds. Goldman's Cecil Medicine. 25th ed. Philadelphia, PA: Elsevier Saunders; 2016:chap 413.

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Review Date 2/27/2016

Updated by: Amit M. Shelat, DO, FACP, Attending Neurologist and Assistant Professor of Clinical Neurology, SUNY Stony Brook, School of Medicine. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.

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