DIAGNOSTIC VALUE OF D-DIMER MEASUREMENT IN PATIENTS SUSPECTED TO HAVE CEREBRAL VENOUS THROMBOSIS

Among the causes of headache, cerebral venous and/or dural sinus thrombosis (CVT) is an important challenge because of its variable clinical presentation, having negative brain CT in up to 30% of cases and unavailability of MRI in some situations. On the other hand as D-Dimer (DD) test has been reported to be a sensitive test for the exclusion of venous thromboembolism, we sought whether it could be useful in the diagnosis of cerebral venous thrombosis. A prospective study of 104 consecutive patients with headache or unusual ischemic stroke (infarction in brain CT, but not compatible with any brunch of cerebral arteries), suggesting CVT was conducted between 2003 and 2005. D-Dimer test determined for all patients in the emergency ward before MRI or MRV was performed. Titers above 500 ng/ml were regarded as positive test. From a total 104 patients, 21 cases (20.2%) were confirmed (by MRI and/or MRV) to have CVT, 20/21 (95.7%) of whom had positive DD test. In the remainder 83 (without CVT) it was only positive in 16.8% (14/83), which was statistically meaningful (P < 0.001). Specificity, sensitivity, negative and positive predictive values of DD test were 83.1, 95.2, 98.6 and 58.8%, respectively, so application of this test would be useful in the diagnosis of CVT and values below 500 ng/ml make acute thrombosis unlikely.