What are the signs and symptoms of cavernous sinus thrombosis?

Signs and Symptoms of Cavernous Sinus Thrombosis

Cavernous sinus thrombosis presents with a distinct triad of fever, headache, and ocular manifestations (chemosis, periorbital edema, ptosis, ophthalmoplegia, vision changes), with cranial nerve VI palsy causing lateral rectus dysfunction being the most characteristic finding. 1

Key Clinical Features

Cardinal Presenting Symptoms

• Fever is one of the most prevalent presenting signs, distinguishing cavernous sinus thrombosis from other forms of cerebral venous thrombosis 1
• Headache may be present but is notably less prominent than in other cerebral venous thrombosis syndromes where it dominates in 90% of cases, which can delay recognition 2
• Ocular manifestations are the hallmark features and include:
  • Chemosis (conjunctival swelling) 1
  • Periorbital edema 1
  • Ptosis (drooping eyelid) 1
  • Ophthalmoplegia (paralysis of eye movements) 1
  • Vision changes or loss 1, 3

Cranial Nerve Involvement

• Cranial nerve VI (abducens) is most commonly affected, resulting in lateral rectus palsy and inability to abduct the eye 1
• Cranial nerves III (oculomotor), IV (trochlear), and V (trigeminal) may also be involved 1
• The pattern of cranial nerve deficits reflects the anatomic course of these nerves through the cavernous sinus 1

Associated Infectious Signs

• Constitutional symptoms including fever and malaise are typical 4
• History of preceding facial infection, particularly sphenoid or ethmoid sinusitis, is common 2, 1
• Middle ear infection, odontogenic sources, or pharyngeal infections may precede the thrombosis 5, 6
• Infections of the "dangerous triangle" (nose and upper lip) are classic precipitants 3

Important Clinical Distinctions

Differences from Other Cerebral Venous Thromboses

Unlike superior sagittal sinus or lateral sinus thrombosis where headache dominates the presentation 4, cavernous sinus thrombosis is distinguished by:

• More prominent infectious/septic features with fever being a key differentiator 1
• Predominance of ocular signs rather than increased intracranial pressure symptoms 1
• Bilateral involvement may occur due to communication between the two cavernous sinuses 1

Temporal Progression

• Symptoms typically develop over several days following the initial facial or sinus infection 1, 5
• The disease may progress rapidly once established, requiring urgent recognition 5, 6
• In the preantibiotic era, mortality was 80-100%; current mortality remains 20-30% despite treatment 5, 6

Critical Pitfalls to Avoid

• Do not dismiss the diagnosis based on absence of severe headache—unlike other cerebral venous thromboses, headache may not be prominent in cavernous sinus thrombosis 2
• Unilateral ocular findings can progress to bilateral involvement due to venous communication between the sinuses 1
• High index of suspicion is required in any patient with facial/sinus infection who develops ocular symptoms or cranial nerve palsies 1, 5
• Permanent neurological sequelae including blindness can occur even with treatment, emphasizing the need for early intervention 5, 3

Systemic Manifestations

• Pulmonary complications may develop 1
• Central nervous system involvement beyond the cavernous sinus can occur 1
• Blood cultures are positive in up to 70% of cases, with Staphylococcus aureus being the most common pathogen 1, 6, 3
• Laboratory testing typically reveals elevated inflammatory markers 1