Venous Sinus Stenosis Diagnosis

Venous sinus stenosis (VSS) is a narrowing of the major dural venous sinuses, typically the transverse and/or sigmoid sinuses, often associated with idiopathic intracranial hypertension (IIH). Diagnosis is based on clinical features and confirmatory imaging and pressure studies.

• Headache (daily, pressure-like)
• Pulsatile tinnitus
• Visual disturbances (transient obscurations, diplopia, papilledema)
• Elevated intracranial pressure (ICP) signs

• First-line, non-invasive
• Findings:
  • Transverse/sigmoid sinus narrowing
  • Collateral venous channels
  • Optic nerve sheath distension
  • Posterior globe flattening

• High-resolution anatomical detail
• Useful at bone-venous interfaces (e.g., transverse-sigmoid junction)

• Gold standard
• Allows dynamic assessment of:
  • Sinus anatomy
  • Trans-stenotic pressure gradient
    • A gradient ≥ 4 mmHg = hemodynamically significant stenosis

• Functional stenosis requires:
  • Anatomical narrowing on imaging AND
  • Elevated trans-stenotic gradient on manometry

• Arachnoid granulations (benign filling defects)
• Sinus hypoplasia (anatomic variant)
• Cerebral venous thrombosis
• Secondary sinus collapse due to raised ICP