Comparison of CT venography with MR venography in cerebral sinovenous thrombosis

OBJECTIVE. The purpose of this study was to compare cerebral CT venography with MR venography and determine the reliability of CT venography in the diagnosis of cerebral sinovenous thrombosis. SUBJECTS AND METHODS. Fifty patients who were clinically suspected of having cerebral sinovenous thrombosis, irrespective of age and sex, underwent cerebral CT venography and MR venography. Projection venograms were displayed using maximum-intensity-projection images for both CT venography and MR venography. The CT venograms were also displayed using the integral algorithm, which depicts the average intensity value of the first five voxels deep in relation to the model surface that is nearest the viewer, allowing direct visualization of the thrombus in the sinuses. All CT venograms and MR venograms were independently evaluated by experienced neuroradiologists. RESULTS. Of these 50 patients, 30 patients were diagnosed as having cerebral sinovenous thrombosis on both CT venography and MR venography. The total numbers of sinuses involved were 81 and 77 (CT venography and MR venography). When MR venography was used as the gold standard, CT venography was found to have both a sensitivity and a specificity of 75-100%, depending on the sinus and vein involved. CONCLUSION. CT venography is as accurate as MR venography for diagnosing cerebral sinovenous thrombosis.