Related Subjects:
Thrombophilia testing
|Antiphospholipid syndrome
|Protein C Deficiency
|Protein S Deficiency
|Prothrombin 20210A mutation
|Factor V Leiden Deficiency
|Antithrombin III deficiency (AT3)
|Cerebral Venous Sinus thrombosis
|Budd-Chiari syndrome
Post-partum period is a risk factor of cortical vein and sinus thrombosis. The combination of CVST and thrombocytopenia had been identified very rarely in those receiving COVID vaccination
About
- Likely underdiagnosed and many cases go untreated
- Headache, papilloedema and a normal CT may mean CVST
- Consider in pregnant or recent pregnancy
Aetiology
- Any procoagulant condition or localised infections
- OCP, Pregnancy or postpartum period
- Hyperviscosity syndromes, smokers
- Dehydration, ecstasy tablets,
- Behcet's disease, Ulcerative colitis, Crohn's disease
- Localised mastoid, ear or sinus infections
- Malignancy: Adenocarcinoma
- Haematological: polycythemia vera, thrombocythemia, leukemia, sickle cell disease
- Direct cranial trauma, neurosurgical procedures in the area of a venous sinus
- Bacterial meningitis
- Antiphospholipid antibody syndrome
- Factor V Leiden, protein S and protein C deficiency
- Prothrombin mutation, and hyperhomocysteinemia.
Venous Anatomy
Anatomy of the thrombosis in order of occurrence
- Superior sagittal sinus: raised ICP, headaches
- Lateral sinuses, Straight sinus and galenic system: can cause bilateral massive deep infarction affecting thalami with akinetic mutism
- Thrombosis of small cortical veins (cortical vein thrombosis)
- Cavernous sinus
- Cortical veins: localised venous infarction and focal cortical signs
- These all drain down into the right and left internal jugular veins
Pathophysiology
- Venous thrombosis leads to oedema and infarction
- Reduced CSF drainage with increased ICP
- Congested oedematous haemorrhagic infarcts
- Subarachnoid bleeding may be seen
Clinical
- Isolated headache or increased ICP (present in ~90% of cases)
- Focal neurological presentations, Subacute encephalopathy
- Cavernous sinus syndrome/multiple cranial neuropathies
- Headache, Nausea, Vomiting, Neck stiffness, malaise
- Cortical vein occlusion gives expected localising signs.
- Dural sinuses ? raised ICP, Sudden headache
- Declining consciousness, Coma, Seizure,
- Neurological deficit like stroke, Papilloedema, VI nerve palsy
- Atypical - psychosis, SAH, cranial nerve palsies, TIA and migraine
Differential
- Idiopathic intracranial hypertension need to exclude CVST especially if
male or non obese
Investigations
- FBC: Thrombocytopenia consider post COIVD vaccine or other haematological condition ? HITT
- D Dimer is usually elevated as it would be for a DVT
- CT: May be normal or maybe wedge-like (haemorrhagic) infarcts not corresponding to the arterial territory. Increased contrast enhancement of falx and tentorium. Cord sign-on non-contrast CT due to fresh clot along falx. Subarachnoid blood may be seen. Empty ? (delta) sign on CT with contrast identifying clot.
- CT with contrast or MRV can show empty delta sign and absence of flow in lumen of sagittal sinus occluded by a venous clot
- MRI and MRV: Can show the extent of infarcts, haemorrhage and evidence of venous thrombosis
- CSF: Raised pressure and protein. LP may help reduce CSF pressure. May be a rise in CSF WCC
- Thrombophilia screen: polycythemia, sickle cell anaemia, deficiencies of proteins C and S, factor V Leiden mutation (resistance to activated protein C), antithrombin III deficiency, homocysteinemia, and the prothrombin G20210 mutation
Worse Prognosis
- Involvement of the Deep vein thrombosis is worse
- Males
- Right lateral sinus thrombosis also worse
Inherited Procoagulant Conditions
| Name | Frequency |
|---|
| Factor V Leiden mutation | 3-7% |
| Prothrombin gene mutation | 1-2% |
| Antithrombin deficiency | 3 |
| Protein C deficiency | 0.3% |
| Protein S deficiency | 0.1% |
Management
- If recent COVID vaccine see below
- LMWH is the standard of care and may be given in a BD formulation to minimise bleed risk. Unfractionated heparin should be used in patients with renal insufficiency or in patients requiring very rapid reversal of anticoagulation (eg, imminent neurosurgical intervention)
- Although their alarming radiological appearance can cause anxiety, haemorrhagic venous infarction, intracranial haemorrhage or isolated subarachnoid haemorrhage are not contraindications for anticoagulant treatment in CVT. See References below.
- Cortical vein thrombosis is also usually treated with anticoagulation (and is our practice) though there are no randomised controlled trials. In a series of 116 patients, most (80%) were treated with anticoagulation, with good outcomes (6% in-hospital mortality)
- Current guidelines recommend using oral vitamin-K antagonist (usually warfarin in the UK) at standard-intensity (target internationalised normalised ratio (INR) 2.5, range 2.0–3.0) for between 3 and 12 months
- Interventional radiology with thrombolysis or clot removal has been done
- Warfarin for 3-6 months followed by antiplatelets. Prolonged Warfarin course e.g. 12 months if no cause found
References