Performance of spin-echo and gradient-echo T1-weighted sequences for evaluation of dural venous sinus thrombosis and stenosis.

摘要

Dural venous sinus abnormalities are clinically important but can potentially be overlooked using various MRI techniques. This study evaluates the diagnostic accuracy of spin-echo (SE) T1-weighted imaging, 3D gradient-recalled echo (GRE) T1-weighted imaging, and contrast-enhanced MR venography (MRV) for the detection of dural venous sinus thrombosis and transverse sinus (TS) stenosis.Seventy-three patients underwent MRI evaluation with unenhanced and contrast-enhanced axial SE T1-weighted imaging, contrast-enhanced sagittal 3D GRE T1-weighted imaging, and contrast-enhanced MRV sequences. Three neuroradiologists each evaluated these 219 total datasets in a randomized blinded fashion for the presence or absence of TS stenosis and for dural venous sinus thrombosis in each of 10 venous sinus segments (730 total segments). Diagnostic performance characteristics and kappa statistics were calculated for each technique.Thirteen patients (37 segments) had suspected dural venous sinus thrombosis by one or more readers; of those 13 patients, nine (23 segments) were thought to have definite thrombosis on contrast-enhanced MRV. Compared with contrast-enhanced MRV, the positive predictive value (PPV) and negative predictive value (NPV) for thrombosis were 60% and 97%, respectively, for both unenhanced and contrast-enhanced SE T1-weighted imaging and 100% and 98% for 3D GRE T1-weighted imaging. Kappa values calculated per venous segment were as follows: 0.41 for SE T1-weighted imaging, 0.72 for 3D GRE T1-weighted imaging, and 0.95 for contrast-enhanced MRV. Thirty patients (58 segments) had TS stenosis suspected by one or more readers; of those 30 patients, TS stenosis was deemed to be definite on contrast-enhanced MRV in 25 patients (50 segments). Compared with contrast-enhanced MRV, the PPV and NPV were 75% and 80%, respectively, for SE T1-weighted imaging and 91% and 92% for 3D GRE T1-weighted imaging for the detection of stenosis. Kappa values calculated per patient were -0.038 for SE T1-weighted imaging, 0.58 for 3D GRE T1-weighted imaging, and 0.98 for contrast-enhanced MRV.Contrast-enhanced 3D GRE T1-weighted imaging is superior to SE T1-weighted imaging for the detection of dural venous sinus thrombosis and TS stenosis but does not substitute for dedicated MRV. Hyperintensity on unenhanced SE T1-weighted imaging is unreliable for the detection of dural venous sinus thrombosis.