Venous sinus thrombosis

Venous sinus thrombosis can occur in any of the venous sinuses, but occur most commonly in the superior sagittal and lateral sinuses (70% of cases). The other famous location for venous sinus thrombosis is the cavernous sinus.

Aetiology may be aseptic or septic.

Aseptic venous sinus thrombosis is associated with

Haematological causes

polycythaemia rubra vera
inherited prothrombotic disorders
Factor V Leiden
Protein S/C deficiency
Antithrombin III deficiency

Post surgical causes
Drugs

OCP
Androgens
Ecstasy

Pregnancy - most commonly postpartum
Inflammatory conditions

Behcet's disease
Sarcoidosis
Inflammatory bowel disease

Malignancies

Septic venous sinus thrombosis is associated with sinusitis, otitis media, bacterial meningitis and also facial/orbital/dental infections.

Presentation of venous sinus thrombosis includes:

headache
focal seizures
paresis
papilloedema
impairment of consciousness

Features suggestive of cavernous sinus thrombosis include

Headache
Ophthalmoplegia
Proptosis
Eyelid swelling
Decreased visual acuity
Chemosis

Investigations

MR-V/CT-V - classically look for empty delta sign - but this is only present in 20%. A CT head without contrast will only show signs of a venous sinus thrombosis in a third of cases.
LP – is not a recommended investigation but if performed may show raised opening pressure, raised protein, pleocytosis

Treatment is to treat cause and anticoagulation.

Complications include PE and in the case of cavernous sinus thrombosis hypopituitarism.

The diagram below is a brief reminder of the anatomy of the cavernous sinus: