Cerebral venous sinus thrombosis

Question 1

What is another way of referring to cerebral venous sinus thrombosis?

Answer 1

intracranial venous thrombosis

Question 2

What is intracranial venous thrombosis?

Answer 2

occlusion of venous vessels in the cranial cavity

Question 3

What proportion of all types of stroke does intracranial venous thrombosis represent?

Answer 3

0.5-3%

Question 4

Which gender and age group are more commonly affected by venous sinus thrombosis?

Answer 4

most common in neonates. women>men, age 20-35 years

Question 5

Which factors are thought to cause increased risk of intracranial venous thrombosis in younger women?

Answer 5

pregnancy, use of COCP

Question 6

What are 7 risk factors for venous sinus thrombosis?

Answer 6

1. COCP
2. Pregnancy and puerperium
3. Prothrombotic haematological conditions: factor V Leiden, protein C deficiency, antiphospholipid syndrome
4. Systemic disease: dehydration, sepsis
5. Cancer
6. Dural AV fistulae
7. ENT infections

Question 7

What are 4 common symptoms of intracranial venous thrombosis?

Answer 7

1. Headache
2. Confusion/ drowsiness
3. Impaired vision (visual obscurations)
4. Nausea/ vomiting

i.e. features of increased ICP

Question 8

What are 5 less common features of the presentation of intracranial venous thrombosis?

Answer 8

1. Seizures
2. Reduced consciousness
3. Focal neurological deficits - hemiparesis, dysphasia, seizures
4. Cranial nerve palsies (CNVI)
5. Papilloedema

Question 9

What are 2 key investigations to perform in cerebral venous sinus thrombosis?

Answer 9

1. Non-contrast CT: hyperdensity in affected sinus
2. CT venogram: filling defect (empty delta sign)

or MRI and MR venogram

Question 10

What will non-contrast CT show in intracranial venous thrombosis?

Answer 10

hyperdensity in the affected sinus

Question 11

What will CT venogram show in cerebral venous thrombosis?

Answer 11

if superior sagittal sinus thrombosis: empty delta sign

Question 12

What is the most common form of dural venous thrombosis?

Answer 12

super sagittal sinus (50% of cases)

Question 13

What 2 forms of intracranial venous thrombosis form the remainder of venous thromboses, after superior sagittal thrombosis?

Answer 13

lateral sinus thromboses and cavernous sinus thromobses

Question 14

What is typically the cause of cavernous sinus thrombosis?

Answer 14

spreading sinus infection

Question 15

What are 4 features of the presentation of cavernous sinus thrombosis?

Answer 15

1. chemosis (oedema of the conjunctiva)
2. exophthalmos
3. peri-orbital swelling
4. cranial nerve palsies (3, 4, 5_a, 6)

Question 16

What is the mainstay of treatment for intracranial venous thrombosis?

Answer 16

LMWH

Address underlying cause

Question 17

What type of cranial nerve palsy is most likely to be seen in cerebral sinus thrombosis generally and why?

Answer 17

CNVI: false localising sign due to raised ICP

Question 18

What type of cranial nerve palsies will be seen in cavernous sinus thrombosis?

Answer 18

CNIII, CNIV, CNV₁, CNVI

Question 19

When would a lumbar puncture be performed in suspected cerebral sinus thrombosis?

Answer 19

if diagnosis not definitive after imaging (not necessary otherwise)

Question 20

What finding on LP is supportive of a diagnosis of cerebral sinus thrombosis?

Answer 20

opening pressure >20cm CSF, after exclusion of a mass lesion

Question 21

What are 5 specific elements of the treatment of cerebral sinus thrombosis?

Answer 21

1. Treat associated infection
2. Anticoagulation with heparin followed by warfarin for 6 months
3. Local thrombolysis therapy- consider if not responding/deteriorating
4. Treat raised ICP (repeated LP/drain/mannitol/decompression craniectomy)
5. Seizures: IV phenytoin or valproate

Question 22

How should anticoagulation be given in cerebral sinus thrombsis?

Answer 22

low molecular weight heparin, followed by warfarin for 6 months/lifelong if prothrombotic conditions exist

Question 23

When should local thrombolysis therapy be considered in cerebral sinus thrombosis?

Answer 23

if not responding to previous measures or deteriorating

Question 24

What are 6 options for treatment of persistent raised ICP in cerebral sinus thrombosis?

Answer 24

1. Repeated lumbar puncture
2. External lumbar drain
3. Lumboperitoneal shunt
4. Mannitol
5. still not resopnding or deteriorating under sedation: ventilation and decompression craniectomy
6. seizures: IV phenytoin or valproate