Value Of Susceptibility Weighted Imaging In Diagnosing Cerebral Venous Thrombosis On 3T MR

Objective:To investigate the value of susceptibility weighted imaging(SWI)in the diagnosis of cerebral venous thrombosis(CVST).Methods:Radiographic findings were evaluated retrospect- Tively in 30 patients with CVST proved by MR or DSA . All the patients were performed with axial T1WI-FLAIR, FSE-T2WI,conventional T2*GRE,SWI and MRV sequences on 3.0T MR. In these cases, 20 patients were examined with DSA. The signal features of thrombosis were observed, at the same time,the phase value (PV) of thrombosis and normal dura sinus on SWI was measured and compared.The sensitivity of T1WI-FLAIR,FSE-T2WI,T2*GRE and SWI in detecting venous thrombosis and secondum cerebral hemorrhage was analyzed statistically.Comparing dilated draining venous detected on T1WI-FLAIR, FSE-T2WI, conventional T2*GRE and SWI.Results:The average phase value (PV) of acute thrombosis(<5d)was -0.642±0.024 and presented hypointense signal on SWI. The average phase value (PV) of subacute stage thrombo- sis(6～15d)was +0.146±0.021 and presented hyperintense signal or the mixed signal dominated by hyperintense signal on SWI. The average phase value (PV) of chronic phase thrombosis ( >16d ) was -0.842±0.015 and presented hypointense signal or the mixed signal dominated by hypointense signal on SWI. The average phase value (PV) of normal dura sinus was +0.136±0.022 and presented hyperintense signal or the mixed signal dominated by hyperintense signal. The average phase value (PV) of sinus thrombosis was different from that of normal dura sinus (P<0.05), The average phase value (PV) of acute,subacute and chronic phase sinus thrombosis was different respectively (P<0.05) .The detection rate of SWI for acute and chronic phase thrombosis was higher than that of T1WI-FLAIR and FSE-T2WI.The detection rate of SWI for subacute thrombosis was lower than that of T1WI-FLAIR and FSE-T2W(IP<0.05).It was not significantly different from that of T2*GRE (P>0.05). There were 94 hemorrhagic lesions at different stages detected on SWI, 74 on T1WI-FLAIR and 67 on FSE-T2WI, 85 on T2*GRE. Dilated draining venous were defected in 18 patients on MinIP of SWI , 5 patients on T2*GRE, 2 patients on FSE-T2WI, There were not dilated draining venous defected on T1WI-FLAIR.Conclusions:SWI was very sensitive to defect venous thrombosis. The sensitivity of SWI in detecting secondum cerebral hemorrhage and dilated draining venous of CVST was significantly higher than that of T1WI-FLAIR, FSE-T2WI and T2*GRE.