相位对比法磁共振血管造影在诊断颅内静脉窦病变中的应用

目的探讨磁共振血管造影(MRA)的相位对比法(PC)在颅内静脉窦病变的表现及诊断价值。方法颅内静脉窦病变52例,包括硬膜静脉窦血管畸形21例、硬膜动静脉瘘7例其中6例为颈内动脉海绵窦瘘(CCF)]、静脉窦血检5例、脑膜瘤侵犯静脉窦19例。MR检查用Siemens公司1.5T扫描仪。扫描序列用PC和时间飞逝(TOF)两种方法。其中28例同时行DSA血管造影。结果PC显示21例硬膜静脉窦血管畸形的瘤巢、输入动脉、输出静脉及静脉窦均为高信号,但瘤巢信号不均匀。PC和TOF两种方法对其输入动脉显示率均为95.2%(20/21),而对输出静脉显示率90.5%(19/21)及76.2%(16/21)。6例CCF表现为患侧海绵窦扩张,眼上静脉增粗。4例横窦和1例上矢状窦的静脉窦血栓PC表现为窦内信号消失,MRI表现为静脉窦内高信号,还可伴有脑叶出血及水肿。19例脑膜瘤侵犯静脉窦,PC显示为静脉窦移位、狭窄及闭塞。结论MRAPC能很好地显示静脉窦结构及其病变。

Phase-contrast magnetic resonance angiography for assessment of intracranial venous sinus lesions

Objective To review the presentations of intracranial venous sinus lesions in phase-contrast(PC) magnetic resonance angiography(MRA) and discuss the diagnostic value of this imaging modality for these lesions.Methods This study involved 52 patients with intracranial venous sinus lesions,including 21 with dural venous sinus malformation,7 dural arteriovenous fistula(6 caroticocaveneous fistula,CCF),5 venous sinus thrombus and 19 meningioma invading the venous sinuses.All patients underwent PC and time-of-flight(TOF) MRA with a 1.5 Tesla MR scanner,with 28 of them undergoing subsequent digital subtraction angiography(DSA).Results PC MRA showed extensive hyperintense signals that identified the lesions,feeding arteries,deferent veins and venous sinuses in 21 cases of dural arteriovenous fistula,but the lesion signals appeared homogeneous.In these cases,PC and TOF MRA had equally good performance in displaying the feeding arteries with success in 20 of the 21 cases(95.2%),whereas the former resulted in a greater rate of deferent vein display 90.5%(19/21)] than the latter 76.2%(16/21),P<0.05].The 6 CCF cases showed ipsilateral cavernous sinus expansion and upper ophthalmic vein dilations.In the 5 cases of venous sinus thrombis,4 had transverse sinus thrombus and 1 superior suggital sinus thrombus.All the cases presented signal disappearance in the sinuses in PC MRA and hyperintense signals in MRI,and some cases had also cerebral superficial hemorrhage and edema.The 19 cases of meningioma invading the venous sinus displayed sinus shift,stenosis and occlusion in PC MRA.Conclusion PC MRA has great advantages in displaying the anatomical structure and lesions of the venous sinuses.