What is the grading of dural venous sinus stenosis in radiology?

From the Guidelines

Dural venous sinus stenosis grading is crucial for determining the appropriate treatment approach, with severe stenosis (>75%) potentially benefiting from stenting procedures, as suggested by the most recent guidelines 1. When evaluating dural venous sinus stenosis, radiologists should assess the location of stenosis, the percentage of luminal narrowing, presence of collateral vessels, and pressure gradients if available.

• The most commonly used grading system categorizes stenosis as mild (0-50% narrowing), moderate (50-75% narrowing), or severe (>75% narrowing) 1.
• Radiological assessment is primarily performed using magnetic resonance venography (MRV), computed tomography venography (CTV), or digital subtraction angiography (DSA), with DSA considered the gold standard due to its superior spatial resolution and ability to measure pressure gradients across stenotic segments.
• A pressure gradient of >8 mmHg across a stenotic segment is generally considered hemodynamically significant. The clinical significance of stenosis grading relates directly to treatment decisions, as patients with severe stenosis and corresponding symptoms like intracranial hypertension may benefit from stenting procedures, while those with milder stenosis might be managed conservatively, as noted in the guidelines for idiopathic intracranial hypertension management 1.
• Accurate measurement techniques include comparing the diameter at the stenotic segment to the normal adjacent segment or to established normal values for that particular venous sinus.
• The role of neurovascular stenting in IIH is not yet established, but it has been reported to lead to an improvement in symptoms of intracranial hypertension, with complications including short-lived ipsilateral headache, stent-adjacent stenosis, and rare cases of vessel perforation or thrombosis 1.
• Long-term antithrombotic therapy is required for longer than 6 months following neurovascular stenting treatment, highlighting the need for careful patient selection and management 1.

From the Research

Dural Venous Sinus Stenosis Grading

• Dural venous sinus stenosis is a condition that can lead to increased intracranial pressure, and its grading is crucial for determining the appropriate treatment options 2.
• The grading of dural venous sinus stenosis is not explicitly mentioned in the provided studies, but it is implied that the severity of stenosis can affect the treatment outcomes 3, 4.

Radiology and Treatment Options

• Radiological imaging plays a crucial role in diagnosing and grading dural venous sinus stenosis, and endovascular treatment options such as stenting are becoming increasingly popular 5, 6, 2.
• The studies suggest that anticoagulation is the initial treatment option, followed by local thrombolysis or rheolytic thrombectomy in cases where anticoagulation is not effective 5, 6.
• Stenting is also considered a viable option for treating dural venous sinus stenosis, especially in cases where medical therapy fails 2, 3, 4.

Complications and Considerations

• The presence of a dural sinus septum can lead to complications during stenting procedures, and anatomical and clinical considerations are essential for successful stent placement 3.
• The duration of dual antiplatelet therapy after venous sinus stenting is also an important consideration, and the studies suggest that longer durations may not necessarily be better 4.