Accuracy of Noncontrast CT Brain in Detection of Cerebral Venous Sinus Thrombosis

Background and Purpose: Increasing concern of cerebral venous thrombosis due to treatable and curable causes of stroke. The diagnosis of cerebral venous sinus thrombosis is challenged due to nonspecific clinical symptomatology. Patients may present at an emergency room with a variety of neurological conditions such as severe headache, weakness, seizure, etc. Neuroimaging, particularly noncontrast cranial computed tomography (NCCT), is an investigation of choice in differentiation and triage the patients for further treatment. CT is sensitive in the detection of acute thrombosis or blood clots in all regions of the body. We hypothesize that NCCT might be sensitive to diagnose cerebral venous thrombosis immediately. Materials and Methods: Retrospectively review the electronic database of our patients, there are 27 patients with cerebral sinus venous thrombosis (SVT) and 4 patients with cerebral deep venous thrombosis (DVT). Other 79 patients present with clinically diagnosed cerebral venous thrombosis but the final result can exclude cerebral venous thrombosis. We use MR imaging and CT venography as the gold standard. Independently reviewed by two neuroradiologists for CT direct sign and CT indirect signs that suggest SVT or DVT. CT direct signs for SVT and DVT are the presence of hyperdensity in the sinus venous or deep venous system (cord sign, attenuated vein sign) and CT indirect signs are the changes in brain parenchyma (brain edema, hemorrhagic infarction). Results: Sensitivity and specificity of NCCT in detection attenuated vein sign and diagnosis DVT are 75% and 100% whereas the sensitivity and specificity of NCCT in detection cord sign and diagnosis SVT are 43.8% and 99.7% as respectively. Conclusions: NCCT might not sensitive in detection of SVT without CT direct sign which needs further investigation. However, NCCT might beneficial for emergency conditions such as DVT patients, cortical vein thrombosis and also in SVT patients with the positive CT direct sign.