Seizure and imaging approach to Cerebral Venous Sinus Thrombosis

Background: Cerebral venous sinus thrombosis (CVST), first reported by Ribes in 1825, is a particular form of ischemic cerebrovascular disease and accounts for 0.5–1% of all cerebrovascular Diseases. Seizures are the presenting feature of cerebral venous sinus thrombosis (CVST) in 12–31.9% of patients. Because the possible causal factors and clinical manifestations of this disorder are many and varied, imaging plays an important role in the diagnosis. The aim of this article is to illustrate the various aspects of CVT on CT scan and MRI. Methods: A literature search using PubMed, Medline, Embase, Scopus, Web of Science, Biomed central, Science Direct, and Google Scholar were completed using the terms ‘cerebral venous thrombosis’,’seizure’,and ‘imaging’. Studies included information on patients with CVT and imaging characteristics. Findings: Unenhanced MRI is a more sensitive technique for detecting CVT than Non-enhanced CT scan (NECT) in patients with seizure. But during late or chronic stages, the presentation pattern in the MRI is more variable. CT venography is considered a good alternative to diagnose CVT, as it is carried out quickly, is accessible and has results that are very similar to those of magnetic resonance imaging (MRI). Studies where CT venography is compared to MRI show a sensitivity and specificity of between 75% and 100% in response to the affected venous sinus. Currently, CVT diagnosis is confirmed with MRI combined with resonance venography (MRV). TOF (time-of-flight) MRV is useful for not only documentation of thrombus but also assessment for recanalization following therapy and in the setting of chronic thrombosis with partial recanalization. Although the results of the research have shown that MRV has a false positive data due to slow venous blood flow without thrombosis. Studies has shown that the venous MRA sequences with injection of gadolinium are now preferred to 2D TOF sequences. MRV with gadolinium allows for a direct assessment of luminal filling similar to that of CTV, with comparable sensitivity and specificity. Moreover, both CTV and contrast-enhanced MRV are superior to the TOF and phase contrast techniques, as complex flow can produce artifact in these sequences. But the most important limitation in contrast-enhanced imaging is patients with severe renal failure. With the aim of removing these limitations, Qi Yang et al (2016), introduced a new technique called Magnetic Resonance Black Blood Thrombus Imaging (MRBTI), as 3D variable-flip-angle turbo spin echo (SPACE), a non-contrast imaging technique which has a very high accuracy in cerebral vein imaging that can overcome the defects of previous protocols. Conclusions: MRBTI technique is free of the risk for allergic reactions and can be used for repeated follow-up exams if necessary. A substantial patient population including pregnant and post-partum women and the elderly with severe kidney insufficiency will greatly benefit from such a radiation free, non-contrast imaging technique. The MRBTI technique can potentially serve as a first-line diagnostic imaging for seizure patients.

کلیدواژه ها:

Seizure ، Cerebral vein thrombosis ، CTV ، MRV ، MRBTI