This, however, requires puncture of the femoral artery with a sheath and advancing a thin tube through the blood vessels to the brain where radiocontrast is injected before X-ray images are obtained. It is therefore only performed if all other tests give unclear results or when other treatments may be administered during the same procedure. D-dimer
There is an association between the D-dimer blood test and cerebral venous sinus thrombosis. This association however is not strong enough to rule out the diagnosis alone. Further tests
In most cases, the direct cause for the cerebral sinus thrombosis is not readily apparent. Identifying a source of infection is crucial; it is common practice to screen for various forms of thrombophilia (a propensity to form blood clots). Pathogenesis
The veins of the brain, both the superficial veins and the deep venous system, empty into the dural venous sinuses, which carry blood back to the jugular vein and thence to the heart. In cerebral venous thrombosis, blood clots usually form both in the veins of the brain and the venous sinuses. The thrombosis of the veins themselves causes venous infarction (damage to brain tissue due to a congested and therefore insufficient blood supply). This results in cerebral edema (both vasogenic and cytotoxic edema), and leads to small petechial haemorrhages that may merge into large haematomas. Thrombosis of the sinuses is the main mechanism behind the increase in intracranial pressure due to decreased resorption of cerebrospinal fluid (CSF).
Clinical practice guidelines now recommend heparin or low molecular weight heparin in the initial treatment, followed by warfarin, provided there are no other bleeding risks that would make these treatments unsuitable. Some experts discourage the use of anticoagulation if there is extensive hemorrhage; in that case, they recommend repeating the imaging after 7–10 days. If the hemorrhage has decreased in size, anticoagulants are started, while no anticoagulants are given if there is no reduction.The duration of warfarin treatment depends on the circumstances and underlying causes of the condition. If the thrombosis developed under temporary circumstances (e.g. pregnancy), three months are regarded as sufficient. If the condition was unprovoked but there are no clear causes or a "mild" form of thrombophilia, 6 to 12 months is advised. If there is a severe underlying thrombosis disorder, warfarin treatment may need to continue indefinitely.Heparin and platelet transfusions should not be used as a treatment for any form of cerebral venous thrombosis caused by immune thrombotic thrombocytopenias including Heparin induced thrombocytopenia (HIT), auto-immune heparin induced thrombocytopenia (aHIT) or vaccine induced immune thrombotic thrombocytopenia (VITT) due to unpredictable effects of heparin on anti-platelet factor-4 antibodies (PF-4). In cases of VITT, intravenous immune globulins (IVIG) are recommended as they block the anti-PF4 antibody interaction with platelets and a non-heparin anticoagulant. In refractory cases, plasma exchange may be used.Thrombolysis (removal of the blood clot with "clot buster" medication) has been described, either systemically by injection into a vein or directly into the clot during angiography.