Neurology · Cerebrovascular Disease
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Suspect in a young woman on oral contraceptives or with a hypercoagulable state presenting with progressive severe headache.
MR venography (MRV) or CT venography (CTV) is the diagnostic test of choice; contrast-enhanced imaging classically shows the empty delta sign.
First-line treatment is anticoagulation with LMWH or unfractionated heparin, even when a hemorrhagic venous infarct is present.
Headache plus seizures and focal deficits that cross arterial territories point to venous rather than arterial infarction.
Non-contrast CT may show a hyperdense cord sign but is frequently normal, so it cannot exclude the diagnosis.
A false-localizing CN VI palsy and papilledema reflect elevated intracranial pressure from impaired CSF absorption.
Severe intracranial hypertension can cause fatal transtentorial herniation if pressure is not controlled.
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A 28-year-old woman taking combined oral contraceptives presents with a progressively worsening headache over 5 days, now accompanied by a generalized seizure. Examination reveals papilledema and a left abducens nerve palsy. Non-contrast head CT shows a small right parietal hemorrhage that does not conform to an arterial territory.
Which of the following is the most appropriate next step in management?
Initiate anticoagulation with low-molecular-weight heparin.
This is cerebral venous sinus thrombosis, and anticoagulation is indicated even in the presence of a hemorrhagic venous infarct because treating the venous congestion prevents further bleeding. The non-arterial hemorrhage, papilledema, and false-localizing CN VI palsy are classic clues, and MRV or CTV would confirm the diagnosis.
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Etiology / Epidemiology
Rare cause of stroke primarily affecting young women, strongly linked to hypercoagulable states, oral contraceptives, and pregnancy.
Clinical Manifestations
Presents with a progressive, severe headache, focal neurologic deficits, seizures, and signs of elevated intracranial pressure like papilledema.
Diagnosis
MR Venography (MRV) or CT Venography (CTV) is the diagnostic test of choice, classically showing the empty delta sign.
Treatment
Immediate anticoagulation with Low Molecular Weight Heparin (LMWH) or unfractionated heparin, even in the presence of hemorrhagic infarction.
Prognosis
Favorable if treated early, but transtentorial herniation from severe intracranial hypertension or massive hemorrhage can be fatal.
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Epidemiology & Etiology
Primarily affects women of childbearing age due to hypercoagulability from oral contraceptive pills (OCPs), pregnancy, or the postpartum period. Other key triggers include inherited thrombophilias like Factor V Leiden, malignancies, and regional parameningeal infections such as mastoiditis. Prothrombotic states are ultimately identified in over 85% of adult cases.
Pertinent Anatomy
The superior sagittal sinus, transverse sinus, and sigmoid sinus are the most frequently thrombosed dural structures. These venous sinuses lack valves, allowing bidirectional flow and facilitating the dangerous spread of infection from the face or middle ear directly into the cranial vault. Occlusion prevents cerebrospinal fluid (CSF) absorption at the arachnoid granulations, directly driving elevated intracranial pressure.
Pathophysiology
Thrombosis of the cerebral veins or dural sinuses causes a dual mechanism of injury. First, venous occlusion increases capillary hydrostatic pressure, leading to cytotoxic and vasogenic edema. Second, impaired CSF absorption at the arachnoid granulations results in profound intracranial hypertension. The severe venous congestion frequently ruptures fragile venules, causing a paradoxical hemorrhagic venous infarction that does not respect classic arterial territories.
Clinical Manifestations
The most common symptom is a gradually worsening, severe headache that mimics idiopathic intracranial hypertension. Patients frequently develop papilledema, visual field deficits, and diplopia due to a false-localizing CN VI (abducens) palsy. Focal neurologic deficits and focal or generalized seizures are highly characteristic of cortical vein involvement. Progression can rapidly lead to altered mental status, coma, and transtentorial herniation if intracranial pressure remains uncontrolled.
Diagnosis
Non-contrast head CT is often the initial test and may show the hyperdense cord sign representing clotted blood in a sinus, but it is frequently normal. The gold standard for diagnosis is MR Venography (MRV) or CT Venography (CTV). Contrast-enhanced imaging classically demonstrates the empty delta sign, a central filling defect surrounded by enhancing dura within the superior sagittal sinus. A normal D-dimer can help rule out the condition in low-risk patients but cannot safely exclude it in high-risk scenarios.
Treatment
The first-line therapy is rapid anticoagulation with Low Molecular Weight Heparin (LMWH) or unfractionated heparin, followed by a transition to oral anticoagulants for 3 to 12 months. Anticoagulation is mandatory even if a hemorrhagic venous infarct is present on imaging, as treating the underlying venous congestion prevents further bleeding. If patients rapidly deteriorate despite adequate anticoagulation, endovascular mechanical thrombectomy is indicated. Seizures should be managed with targeted antiepileptics, but prophylactic use is not routinely recommended unless a cortical hemorrhagic lesion is present.
Prognosis
Complete recovery occurs in the majority of patients treated promptly, though chronic headaches or visual field deficits may persist. Severe cases complicated by status epilepticus, deep venous system involvement, or massive hemorrhage carry a significantly higher mortality rate. Patients require long-term monitoring for recurrent venous thromboembolism (VTE) and targeted screening for underlying inherited thrombophilias.
Differential Diagnosis
Idiopathic Intracranial Hypertension: Presents with progressive headache and papilledema in young obese women, but MRV/CTV imaging is completely normal.
Arterial Ischemic Stroke: Causes sudden-onset focal deficits that strictly respect a single arterial vascular territory, unlike venous infarcts.
Subarachnoid Hemorrhage: Manifests as a sudden thunderclap headache rather than progressive pain, with hyperdense blood visible in the basal cisterns on CT.
Meningitis: Features headache and altered mental status but prominently includes fever, nuchal rigidity, and inflammatory CSF changes.