Venous Sinus Thrombosis (CVST) +/- Intracranial Hemorrhage

FACTS

  • Pathology: Thrombus in a dural venous sinus and/or cortical veins → impaired venous outflow → venous congestion → edema → venous infarct ± hemorrhagic conversion.
  • Presentations to not miss: New/worst headache, seizure, focal deficit, encephalopathy, papilledema/ICP crisis.
  • Management cornerstone: Therapeutic anticoagulation—even with intracranial hemorrhage— unless clear contraindication; decompressive surgery for malignant edema/herniation.

HPI

Universal ROS
  • Risk factors: Recent pregnancy/post-partum, OCP/HRT, dehydration, infection (sinus/ear), cancer, known thrombophilia, autoimmune disease, trauma, lumbar puncture or intracranial procedure.
  • Vision changes, aphasia, hemiparesis/hemisensory loss.
  • Signs of raised ICP: Nausea/vomiting, transient visual obscurations, diplopia (VI palsy).
  • Anticoagulant/antiplatelet use and bleeding history.

PHYSICAL EXAM

universal neuro exam
  • emphasis on cranial nerves/vision: Papilledema (if ophthalmoscopy available), CN VI palsy.
  • Focal deficits: Aphasia, hemiparesis; compare to vascular territory (often non-arterial pattern).
  • Meningeal signs if infectious suspicion.

IMAGING

CT head (non-contrast):
  • May be normal; hyperdense sinus sign; venous infarcts (often hemorrhagic, cortical–subcortical, not arterial-territory).
CTV (preferred rapid test):
  • Filling defect in dural sinus/cortical vein; absent/defective opacification.
MRI brain with MRV:
  • T1/T2/FLAIR: Venous infarcts, edema; blooming on SWI for hemorrhage.
  • Post-contrast/T1: Empty delta sign (contrast around non-enhancing thrombus in SSS).
  • MRV: Absent flow in involved sinus/veins (confirm extent).

A/P

  • Admit to ICU or step-down if any hemorrhage, edema, seizures, or fluctuating exam.
  • Anticoagulation (even with ICH, unless active uncontrolled bleed/herniation requiring immediate surgery)
    • Start therapeutic heparin:
      • UFH infusion (titrate to anti-Xa/aPTT), preferred if rapid reversal may be needed (OR window).
      • LMWH (e.g., enoxaparin 1 mg/kg BID) acceptable if stable and no planned urgent procedures.
    • Transition to oral anticoagulation after stabilization:
      • DOAC (e.g., apixaban/rivaroxaban) or warfarin (INR 2–3).
      • Duration: 3–6 months if transient risk factor; 6–12+ months if unprovoked or persistent thrombophilia (coordinate with neurology/hematology).
  • Hypercoagulable panel (antiphospholipid, factor V Leiden, prothrombin G20210A, protein C/S, antithrombin) — time with anticoagulation/acute phase in mind; may repeat outpatient.

Empty Delta Sign

If you see a triangular non-opacified area in the posterior superior sagittal sinus surrounded by enhancing dura on contrast CT → think “empty delta = venous clot.”
  • Definition: The empty delta sign is a classic radiologic finding on contrast-enhanced CT or MRI that indicates superior sagittal sinus thrombosis.
  • Appearance: A triangular (delta-shaped) filling defect in the superior sagittal sinus, outlined by contrast-enhancing dura and collateral veins, giving the center an “empty” (non-opacified) appearance.
  • Timing: Usually seen on contrast-enhanced studies (CT or MR venography) after the first few days of thrombus formation, once enhancement of the sinus wall develops.
  • Pathophysiology: The central non-enhancing region represents thrombus, while the enhancing margins represent dural venous collateral circulation.
  • Clinical correlation: Strongly suggestive of cerebral venous sinus thrombosis, most commonly involving the superior sagittal sinus; should prompt immediate anticoagulation unless contraindicated.
Empty Delta Sign
Empty Delta Sign