Cavernous Sinus Thrombosis Clinical Presentation

Updated: Oct 02, 2023
  • Author: Rahul Sharma, MD, MBA, FACEP; Chief Editor: Barry E Brenner, MD, PhD, FACEP  more...
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The early signs and symptoms of cavernous sinus thrombosis (CST) may not be specific. A patient who presents with headache and any cranial nerve findings should be potentially evaluated for CST. The most common signs of CST are related to the anatomical structures affected within the cavernous sinus, as depicted in the image below.

Anatomy of cross section of cavernous sinus showin Anatomy of cross section of cavernous sinus showing close proximity to cranial nerves and sphenoid sinus.

Patients generally have sinusitis or a midface infection (most commonly a furuncle) for 5-10 days. In as many as 25% of cases in which a furuncle is the precipitant, it will have been manipulated in some fashion (eg, squeezing, surgical incision).

The clinical presentation is usually due to the venous obstruction as well as impairment of the cranial nerves that are near the cavernous sinus.

Headache is the most common presentation symptom and usually precedes fevers, periorbital edema, and cranial nerve signs. The headache is usually sharp, increases progressively, and is usually localized to the regions innervated by the ophthalmic and maxillary branches of the fifth cranial nerve.

In some patients, periorbital findings do not develop early on, and the clinical picture is subtle.

Some cases of CST may present with focal cranial nerve abnormalities possibly presenting similar to an ischemic stroke. [2]

As the infection tracts posteriorly, patients complain of orbital pain and fullness accompanied by periorbital edema and visual disturbances.

Without effective therapy, signs appear in the contralateral eye by spreading through the communicating veins to the contralateral cavernous sinus. Eye swelling begins as a unilateral process and spreads to the other eye within 24-48 hours via the intercavernous sinuses. This is pathognomonic for CST.

The patient rapidly develops mental status changes including confusion, drowsiness, and coma from CNS involvement and/or sepsis. Death follows shortly thereafter.



Other than the findings associated with the primary infection, the following signs are typical for cavernous sinus thrombosis:

Periorbital edema may be the earliest physical finding.

  • Chemosis results from occlusion of the ophthalmic veins.

  • 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. [3]

  • Ptosis, mydriasis, and eye muscle weakness from cranial nerve III dysfunction

Manifestations of increased retrobulbar pressure follow.

Signs of increased intraocular pressure (IOP) may be observed.

  • Pupillary responses are sluggish.

  • Decreased visual acuity is common owing to increased IOP and traction on the optic nerve and central retinal artery.

Hypoesthesia or hyperesthesia in dermatomes supplied by the V1 and V2 branches of the fifth cranial nerve.

Appearance of signs and symptoms in the contralateral eye is diagnostic of CST, although the process may remain confined to one eye.

Meningeal signs, including nuchal rigidity and Kernig and Brudzinski signs, may be noted.

Systemic signs indicative of sepsis are late findings. They include chills, fever, shock, delirium, and coma. [4]



Most cases of septic cavernous sinus thrombosis (CST) are due to an acute infection in an otherwise healthy individual. However, patients with chronic sinusitis or diabetes mellitus may be at a slightly higher risk.

The causative agent is generally Staphylococcus aureus, although streptococci, pneumococci, and fungi may be implicated in rare cases.



Complications of cavernous sinus thrombosis (CST) may include the following:

  • Septic emboli

  • Blindness

  • Cranial nerve palsies

  • Sepsis and shock [4]