Cerebral venous sinus thrombosis
Thrombosis of the dural venous sinuses or cortical veins that impairs cerebral venous drainage and CSF absorption, producing headache, papilledema, focal deficits, or seizures; MRI/MRV or CT venography establishes the diagnosis, and anticoagulation is first-line even when hemorrhagic venous infarction is present.
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What this article covers
- Overview
Definition: cerebral venous sinus thrombosis (CVST) is occlusion of one or more dural venous sinuses (most often the superior sagittal or transverse sinus) or cortical veins by thrombus, impairing venous outflow and CSF resorption.
- Epidemiology
Sex and age skew: disproportionately affects women of reproductive age, reflecting pregnancy, the puerperium, and oral contraceptive exposure as major precipitants.
- Risk factors
Hormonal and reproductive: pregnancy and the puerperium; oral contraceptive or other estrogen-containing therapy.
- Pathophysiology
Outflow obstruction: thrombus occludes a dural sinus or cortical vein, raising venous and capillary pressure upstream of the occlusion.
- Clinical features
Headache: the most common and often only symptom; typically diffuse, progressive over days, worse with Valsalva, and unremitting, though it can also present with sudden severe onset mimicking subarachnoid hemorrhage.
- Differential diagnosis
Subarachnoid hemorrhage: thunderclap headache with meningismus; noncontrast CT and, if negative, lumbar puncture with xanthochromia distinguish it, whereas CVST headache is more often subacute and…
- Diagnosis
Establishing the diagnosis: MRI of the brain with MR venography, or CT venography, showing a filling defect or absence of flow in a dural sinus or cortical vein, confirms CVST; noncontrast CT is…
- Management
Anticoagulation is first-line and should be started as soon as the diagnosis is confirmed: low-molecular-weight heparin, enoxaparin 1 mg/kg subcutaneously every 12 hours; preferred when renal…
- Complications
Venous infarction and hemorrhage: parenchymal injury that can produce permanent focal deficits.
- Prognosis
Generally favorable: most patients recover well with anticoagulation, and partial or complete sinus recanalization is common over subsequent months.
- Prevention
Avoid known precipitants when possible: maintain hydration, especially in children and in illness with vomiting or diarrhea; treat mastoiditis, sinusitis, and dental infections promptly to prevent septic extension.
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Related articles
- Ischemic stroke
Ischemic stroke is sudden focal neurologic deficit from arterial occlusion confirmed by infarction on neuroimaging. Diagnosis relies on urgent noncontrast head CT to exclude hemorrhage; treatment is IV alteplase within 4.5 hours and mechanical thrombectomy for large-vessel occlusion within an extended window, followed by antiplatelet therapy and risk-factor control.
- Subarachnoid hemorrhage
Subarachnoid hemorrhage is sudden bleeding into the subarachnoid space, most often from a ruptured saccular (berry) aneurysm, presenting as the worst headache of a patient's life. Diagnosis is noncontrast head CT, then lumbar puncture if CT is negative, then catheter angiography to define the aneurysm; management is early aneurysm securement, blood pressure control, and nimodipine to reduce delayed cerebral ischemia from vasospasm.
- Idiopathic intracranial hypertension (pseudotumor cerebri)
Idiopathic intracranial hypertension (formerly pseudotumor cerebri) is raised intracranial pressure of unclear cause, without a mass lesion or hydrocephalus, occurring mainly in obese women of childbearing age and presenting with headache, papilledema, and visual symptoms. Diagnosis requires an elevated lumbar puncture opening pressure with normal CSF and normal or empty-sella imaging; treatment centers on weight loss and acetazolamide to protect vision, with surgery reserved for medically refractory disease.
- Increased intracranial pressure
Sustained intracranial pressure above 20-22 mmHg from mass effect, edema, hydrocephalus, or venous outflow obstruction, diagnosed by clinical signs plus invasive monitoring and treated stepwise with head elevation, hyperosmolar therapy (mannitol or hypertonic saline), CSF diversion, and decompressive surgery when refractory.
- Seizure (first, single, or provoked)
A first or provoked seizure requires a focused history to distinguish it from syncope or a nonepileptic event, urgent glucose and electrolyte testing, brain MRI, and outpatient EEG; an unprovoked seizure with normal imaging and EEG usually does not require antiepileptic drug therapy, since epilepsy is defined only after a second unprovoked seizure or a high-risk first one.