Intracranial venous thrombosis

Question 1

What are the two main types of intracranial venous thrombosis? What are some of the signs of both?

Answer 1

Dural venous sinus thrombosis: symptoms come on gradually over days or weeks.
cortical vein thrombosis: stroke-like focal symptoms develop over days, headache may be sudden, seizures are common

Question 2

What are the common locations of a dural venous sinus thrombosis? What are some of the signs for each?

Answer 2

Sagittal sinus: most common, headache, vomiting, seizures, decreased vision, pappiloedema
transverse sinus: second most common, headache, +/- mastoid pain, focal CNS signs, seizures, papilloedema
sigmoid sinus: cerebellar signs, lower cranial nerve palsies
inferior petrosal sinus: V and VI cranial nerve palsies, which with temporal and retro-orbital pain, comprise Gradenigo’s syndrome
cavernous sinus: often due to spread from facial pustules or folliculitis, causing headache, chemosis, oedematous eyelids, proptosis, painful ophthalmoplegia, fever

Question 3

What are the signs of a cortical vein thrombosis?

Answer 3

encephalopathy
focal seizures
headache (thunderclap)
slowly evolving focal deficits

Question 4

What is the differential diagnosis for an intracranial venous thrombosis?

Answer 4

subarachnoid haemorrhage
meningitis
encephalitis
intracranial abscess
arterial infarction

Question 5

What are the investigations that should be ordered for an intracranial venous thrombosis?

Answer 5

Exclude SAH if thunderclap headache
check for signs of meningitis
CT/MRI
Lumbar puncture - if raised open CSF Pa with persistent headache and SAH excluded. CSF may be normal or show RBCs and xanthochromia