The Dedicated Venous Sinus Thrombectomy Stent for Endovascular Treatment of Cerebral Venous Sinus Thrombosis.

Endovascular mechanical thrombectomy is reserved for the treatment of refractory cerebral venous sinus thrombosis (CVST) in the scenario of clinical deterioration in spite of appropriate anticoagulant therapy. However, due to the vascular anatomic and pathophysiological differences, the present used devices,such as stent retriever for arterial occlusion ,aspiration system and balloon catheter cannot provide optimal restoration of venous outflow for high load venous sinus thrombosis.This is a prospective, single-center, open-label, randomized, controlled , non-inferiority clinical trial to evaluate the safety and efficacy of the dedicated venous sinus thrombectomy stent ,which is a novel NiTi- braided Stent Retriever compared to balloon catheter used before in our center. Patients are eligible if they have a radiologically proven CVST, a high probability of poor outcome.

The trial aims to randomize 60 patients with a 1:1 allocation to receive the dedicated venous sinus thrombectomy stent or balloon catheter.

The primary outcome is the success rate of immediate recanalization.The most important secondary outcomes are mRS and mortality rate at 90 days. The intracranial hemorrhage and other adverse events after post-operative 24 hours and 7 days are the principal safety outcomes.

Inclusion criteria

• Cerebral venous sinus thrombosis (from onset to randomization less than 28 days) confirmed by cerebral angiography, magnetic resonance venography or computed tomographic venography
• Severe form of CVT with a high chance of incomplete recovery, as defined by the presence of one or more of the following risk factors

• Clinical deterioration or progression despite anticoagulation
• Stupor, Coma (Glasgow coma scale < 9) or mental status disorder
• Involvement of multiple sinus veins results in severe high cranial pressure and rapid vision loss
• Venous infarction or intracranial hemorrhage with high load venous sinus thrombosis
• Thrombosis of the straight sinus
• The subject (or his/her guardian) agrees to participate in this study and signs the informed consent

Exclusion criteria

Age less than 18 years Duration from onset to randomization more than 28 days Recurrent CVST Pregnancy (women in the puerperium may be included) Isolated cavernous sinus thrombosis or isolated cortical vein thrombosis Clinical and radiological signs of impending transtentorial herniation due to large space-occupying lesions and 4th ventricle compression and hydrocephalus, which requires emergency surgery Recent (< 2 weeks) major surgical procedure (does not include lumbar puncture) or severe cranial trauma Contraindication for anti-coagulant or thrombolytic treatment

• documented generalized bleeding disorder
• concurrent thrombocytopenia (<100 x 10E9/L)
• severe hepatic or renal dysfunction, that interferes with normal coagulation
• gastrointestinal tract hemorrhage (< 3 months, not including hemorrhage from rectal hemorrhoids) Any known serious condition (such as terminal cancer) with a poor short term (1 year) prognosis independent Known allergy against contrast used during endovascular procedures or the thrombolytic or anticoagulation drug used Previously legally incompetent prior to CVST No informed consent Other conditions judged by the researcher to be unsuitable for inclusion.