磁敏感加权成像及其PV值测定对不同时期脑静脉窦血栓的诊断价值

目的比较不同序列磁共振成像对不同时期脑静脉窦血栓形成(CVST)的敏感性,探讨磁敏感加权成像(SWI)序列及其相位值(PV)测定对CVST的诊断意义。方法采用3.0 T磁共振系统,对30例患者进行轴位T1WI、T2WI、T2*WI、SWI及MRV序列检查,其中20例患者进行DSA检查。观察不同序列静脉窦血栓的信号特点,定量测量静脉窦血栓的PV值变化,并比较不同序列对不同时期CVST检出的敏感性。结果正常静脉窦PV值为+0.136±0.022,SWI呈高信号。急性期(≤5d)静脉窦血栓PV值为-0.642±0.024,SWI呈低信号;亚急性期(6～15d)静脉窦血栓PV值为+0.146±0.021,SWI呈高信号或以高信号为主的混杂信号;慢性期(≥16d)静脉窦血栓PV值为-0.842±0.015,SWI呈低信号。静脉窦血栓PV值与正常静脉窦PV值差异有统计学意义(P<0.05)。急性期、亚急性期及慢性期静脉窦血栓PV值差异有统计学意义(P<0.05)。SWI序列对急性期和慢性期(97.20%,92.30%)静脉窦血栓的检出率高于T1WI(63.80%,38.40%)和T2WI(0.00%,30.70%)序列,对亚急性静脉窦血栓(48.00%)的检出率低于T1WI(100%)和T2WI(72.00%)序列。SWI和T2*WI对静脉窦血栓的检出率差异有统计学意义(P﹥0.05)。结论 SWI序列对急、慢性期CVST的检出有较高的敏感性,PV值测定能够为CVST的诊断提供客观的量化标准。

The value of susceptibility weighted imaging in diagnosis of cerebral venous thrombosis of different stages

Objective To compare the sensitivety of different sequences on MR in cerebral venous thrombosis(CVST) of different stages,and investigated the value of susceptibility weighted imaging(SWI) in the diagnosis of CVST.Methods All the patients with CVST were performed with axial T1WI,T2WI,T2*WI,SWI and MRV sequences on 3.0T MR system.In these cases,20 patients were examined by DSA.The signal features in thrombosis of different stage were observed,and the phase value(PV) of thrombosis and normal dura sinus were measured on SWI.The sensitivity of T1WI,T2WI,T2*WI and SWI in detecting venous thrombosis of different stages were compared.Results The PV of acute thrombosis(≤5d)was-0.642±0.024 and presented hypointense signal on SWI.The PV of subacute thrombosis(6-15d)was +0.146±0.021 and presented hyperintense signal or the mixed signal dominated by hyperintense signal on SWI.The PV of chronic thrombosis(≥16d)was-0.842±0.015 and presented hypointense signal or the mixed signal dominated by hypointense signal on SWI.The PV of normal dura sinus was +0.136±0.022 and presented hyperintense signal or the mixed signal dominated by hyperintense signal.The PV of sinus thrombosis was different from that of normal dura sinus(P<0.05).The PV of acute,subacute and chronic thrombosis was different respectively(P<0.05).The detection rate of SWI in acute and chronic thrombosis(97.20%,92.30%) was higher than that of T1WI(63.80%,38.40%)and T2WI(0.00%,30.70%).The detection rate of SWI in subacute thrombosis(48.00%) was lower than that of T1WI(100%) and T2WI(72.00%)(P<0.05).It had not significantly different from that of T2*WI(P>0.05).Conclusion The sensitivity of SWI is significantly higher than that of T1WI,T2WI and T2*WI in detecting CVST.SWI especially was important applied value in diagnosis of early CVST.