磁敏感加权成像对脑静脉(窦)血栓形成的诊断价值

目的 探讨磁敏感加权成像(SWI)对脑静脉(窦)血栓形成(CVST)的诊断价值.资料与方法 回顾性分析18例经MR或DSA确诊的CVST患者的影像资料.18例全部行常规MRI、磁共振静脉成像(MRV)及SWI检查.其中15例同时行T2*WI梯度回波(GRE)检查,10例进行了DSA检查.结果 13例急性期CVST,血栓在T1、WI、T2、WI显示不理想,而在T2*WI GRE呈典型低信号.18例CVST,在SWI检查中均可见引流区小静脉数量增多,管径增粗,信号减低,同时发现更多的微小出血灶.但SWI对血栓本身的显示较困难,其他序列如T1WI、T2WI、T2*GRE或MRV具有优势.在全部MRV中,均可见静脉信号缺失.结论 SWI较常规MR序列能发现更多CVST的征象,有更多的诊断价值.     

静脉性脑梗死的磁敏感加权成像表现

目的 研究静脉性脑梗死的磁敏感加权成像(SWI)表现及其临床应用价值.资料与方法 回顾性分析25例经MR或DSA确诊的脑静脉窦血栓(CVST)患者的影像资料,所有患者均伴有静脉性脑梗死.25例均行T_1WI、T_2WI、2D T_2~*梯度回波(GRE)、SWI及磁共振静脉成像(MRV)检查.其中,18例行DSA检查,22例行CT检查.结果 20例为出血性静脉脑梗死,5例为非出血性静脉脑梗死.SWI示16例(16/20)出血灶的数目较TISE序列增多,显示18例(18/20)的出灶灶较T_2FSE增多,显示12例(12/20)的出血灶较2D T_2~* GRE序列增多.其中,17例(17/25)的SWI最小强度投影(MinIP)图像梗死区可见许多扩张的小静脉,其他序列未见此征象.结论 SWI可以发现静脉性脑梗死中更多的出血灶和扩张的引流静脉,对诊断静脉性脑梗死和判断静脉性脑梗死患者的病情可能会有更大帮助.     

脑磁共振静脉成像

目的：磁共振静脉成像(MRV)已被广泛应用于颅内静脉系统检查，特别是用来评价静脉窦血栓形成。本研究的目的是评价脑MRV描述正常颅内静脉系统解剖和变异的作用，评价它在诊断硬脑膜窦血栓形成过程中潜在的误诊因素。材料和方法：对79例常规磁共振表现正常的MRV图像进行分析，观察硬脑膜窦和主要静脉的表现和缺失情况。其中7例志愿者接受了MRV和3DPCMRA两种方法检查。结果：上矢状窦、直窦、Galen静脉和大脑内静脉显示率为100％，枕窦显示率为10％，基底静脉显示率为92％。横窦血流间隙显示率约为34％，均出现在非优势侧横窦，优势侧横窦没有出现流动间隙。结论：MRV是有效的评价颅内静脉系统方法。常规MR表现正常者中有34％可以发现横窦流动间隙，这些流动间隙不应被误诊为静脉窦血栓形成。     

三维增强磁共振静脉成像评价颅内静脉系统

目的:比较三维增强FLASH序列和2D TOF序列MR静脉成像(MRV)对颅内静脉系统的诊断价值.方法:本组11例中健康志愿者6例(正常组),脑静脉窦血栓形成患者5例(病变组),均同时行3D增强FLASH和2D TOF序列MRV扫描,病变组5例患者同时行DSA检查.将脑内主要静脉(14支)的显示情况分为3级:满意显示,一般显示和未显示.比较两种扫描方法对脑内静脉和静脉血栓的显示情况.结果:正常组中三维增强FLASH和2D TOF序列对所观察的14支脑静脉的满意显示率、一般显示率和未显示率分别为88.10%,5.95%,5.95%和30.95%,53.57%,15.48%.三维增强FLASH未显示结构主要为下矢状窦.病变组5例中DSA共发现12处血管病变,三维增强FLASH显示优于2D TOF 10处,两者相仿2处.结论:三维增强FLASH对脑静脉系统的显示优于2D TOF序列,可以提供高质量的脑内静脉结构的图像,对诊断脑静脉内血栓形成有重要临床价值.     

上矢状窦栓塞大脑髓静脉改变的SWI研究

目的:利用磁敏感加权成像(SWI)技术探讨上矢状窦栓塞后大脑髓静脉的改变。方法:对10例上矢状窦栓塞患者和年龄、性别相匹配的10例健康志愿者行常规MRI、MRV和SWI,应用计算机后处理软件对SWI图像进行处理,得到校正后的磁矩图和相位图,将大脑髓静脉增多扩张脑白质区作为病变组、其对侧镜像正常脑白质区为对照组1,健康志愿者与病变组相同位置脑白质区为对照组2,分别测量相位值,进行比较,统计学分析采用单因素方差分析。结果:病变组选择髓静脉增多扩张脑白质区37处测得相位值为-0.571～0.104,平均-0.051;对照组1相位值为-0.047～0.079,平均0.010;对照组2相位值为-0.045～0.056,平均0.014;病变组相位值低于对照组1和对照组2,差异有统计学意义(P<0.001);对照组1和对照组2相比,二者无显著差异(P=0.790)。结论:磁敏感加权成像(SWI)能明显显示上矢状窦栓塞患者大脑髓静脉的增多、扩张,并可利用相位信息为其提供量化依据。     

3.0T MR磁敏感加权成像在脑梗死伴出血性转变中的应用价值

目的 探讨磁敏感加权成像技术(SWI)在脑梗死伴出血性转变(HT)中的应用价值.方法 对13例HT患者采用3.0T MR行常规MRI及SWI检查,部分行T2*WI、MRA、MRV、MRS.结果 SWI检测出血优于常规MRI序列及T2*WI.Min图能显示出血区血管纹理.8例脑梗死区静脉减少(3例明显减少),1例显示增多.5例示梗死周围静脉扩张.1例示动脉内血栓形成,呈条状低信号.结论 SWI在脑梗死伴HT的诊断、监测和决策临床治疗方案有重要价值.     

磁共振脑静脉系血管成像技术及其临床应用

目的探讨磁共振脑静脉系血管成像的技术方法和最佳扫描方案，评价磁共振静脉系血管成像技术(MR venography，MRV)对静脉系疾病的诊断价值及临床意义。方法采用二维时间飞跃法MR血管造影(2D-TOF-MRA)、二维相位对比血管造影(2D-PCA)和三维对比增强MR血管造影(3D-CE-MRA)3种血管成像技术分别对20例健康志愿者和20例临床或MRI疑有静脉系疾病的患者行MRV成像，并采用最大强度投影(MIP)、多平面或曲面重建(MPR)及数字减影MRA(DSMRA)技术对图像进行后处理，观察脑静脉系在MRV中的显示情况及脑静脉系疾病在MRV中表现形式，制定脑静脉系成像的最佳方案。结果本组经3D-CE-MRA静脉系成像诊断为13例颅内静脉窦血栓形成(CVST)及7例颅内肿瘤累及静脉系的阳性显示率为100％，均经临床治疗复诊及手术证实。2D-PCA及2D-TOF-MRA对细小引流静脉显示欠佳，且2D-TOF-MRA对复杂区域内静脉血管亦显示欠佳。结论3D-CE-MRA结合2D-PCA及2D-TOF-MRA静脉成像技术形成全脑静脉系成像，为脑静脉系的最佳成像方案，对临床术前评估和指导治疗有极其重要的意义。     

颅内静脉系统的时间分辨MR血管成像:另外一种MR静脉成像技术

正摘要目的对照对比剂动力学时间分辨影像(TRICKS)MR血管成像(MRA)与二维时间飞跃(TOF)MR静脉成像(MRV)、三维对比增强(CE)MRV正常脑静脉与硬膜静脉窦的影像显示。方法35例连续病人纳入本前瞻性研究。所有病人均接受TOF MRV、TRICKS MRA与CE MRV检查;单一剂量静脉对比剂注射用于后     

磁敏感加权成像在脑血管畸形疾病中的应用

目的 评价磁敏感加权成像在诊断脑血管畸形性疾病中的应用价值.方法 58例脑血管畸形(海绵状血管瘤、动静脉血管畸形及静脉血管畸形)患者行1.5T MRI检查,包括SE序列,SWI序列,部分还包括MRI增强、DWI、T2*WI、MRA和MRV.SWI所得到图像资料经过工作站进行后处理,获得SWI磁化率加权图、SWI MinIP图和SWI相位图.将所有资料进行对比分析,比较SWI相对于常规序列在脑血管畸形疾病中的诊断价值.结果 30例海绵状血管瘤患者SWI的磁化率加权图像特点表现为完全低信号6个,另24个表现为低信号中伴点状、斑状等或高信号,周围环绕较宽低信号,出现明显的"铁环征".病变范围的显示较常规序列范围大.在14例动静脉血管畸形中,SWI较常规序列多发现7例动静脉血管畸形(AVM),有10例同时显示供血动脉及引流静脉.在14例静脉血管畸形中,SWI较常规序列多发现病变8处,并能同时显示更多细小髓静脉及引流静脉.结论 SWI能够较常规扫描序列更好的对脑血管畸形,尤其是不典型的海绵状血管瘤做出诊断.     

脑静脉性血管瘤的MRI及磁敏感加权成像表现

目的 评价磁敏感加权成像(susceptibility weighted imaging,SWI)在脑静脉血管畸形的诊断价值.方法 回顾性分析16例脑静脉性血管瘤(CVH)的MRI表现.16例均行MRI平扫,其中10例行MR增强扫描,10例行SWI检查.结果 16例中,发生于小脑半球6例,顶叶4例、额叶2例、颞枕叶2例、枕叶1例,侧脑室旁1例,伴发海绵状血管瘤1例.16例中,MRI平扫显示病灶13例,表现为管状、小圆状低信号;10例MR增强检查显示所有病灶,表现为"水母头"样强化;10例SWI均能清晰显示病灶,表现为"水母头"样低信号影;结论 MRI结合SWI是诊断CVH的无创和有效手段.     

The dural entrance of cerebral bridging veins into the superior sagittal sinus: an anatomical comparison between cadavers and digital subtraction angiography

Introduction Intracranial venous structures have received increasing attention due to improved neuroimaging techniques and increased awareness of cerebral venous disease. To date, few studies have attempted to investigate the dural entrance of the cerebral bridging vein (BV). The aim of this study was to use the superior sagittal sinus (SSS) as an example to identify anatomical features of the dural entrance of the BVs into the SSS in both human cadavers and digital subtraction angiography (DSA) images. Methods A total of 30 adult and 7 fetal human cadavers and 36 patients were examined with anatomical dissections, vascular casting and DSA. The number, diameter and angle of the BVs entering the SSS were measured and compared between the cadavers and DSA images. Results The results demonstrated that (1) the way a BV entered the SSS varied in three dimensions, and thus the BV dural entrance was difficult to precisely localize by DSA, (2) the distribution pattern of the dural entrance of the BVs into the SSS was relatively constant and a nontributary segment of the SSS was centered at the coronal suture and was identifiable by DSA, and (3) nearly all the BVs (97%, 561/581) entered the SSS at an angle opposite to the direction of blood flow. Conclusion Unique anatomical features of the dural entrance of a BV into the SSS should be considered in neuroimaging interpretation of the sinus and its associated veins.     

Variations of the superior sagittal sinus and bridging veins in human dissections and computed tomography venography

ObjectivesThe aim of the present study was to examine the superior sagittal sinus (SSS) and bridging veins (BVs) from an anatomical, neurosurgical and radiological perspective.MethodsComputed tomography venographies (CTVs) of 30 patients and 9 cadaveric dissections of human SSS were analyzed.ResultsCTV and cadavers showed most BVs emptying into the SSS close by (±3 cm) and distal to the coronary suture (74% in CTV, 62% in cadavers).ConclusionsImportant anatomical information can be drawn from cerebral CTV for neurosurgical preoperative planning.     

仿真开颅手术显示大脑浅静脉及其与脑膜瘤关系的应用价值研究

目的 评价仿真开颅手术在显示大脑浅静脉及其与大脑凸面、矢状窦旁及大脑镰旁脑膜瘤关系中的作用.方法 应用仿真开颅手术和三维对比增强MR静脉成像技术(3D CE-MRV)前瞻性地检查49例大脑凸面、矢状窦旁及大脑镰旁脑膜瘤,并进行图像后处理.采用t检验比较两种技术对大脑浅静脉显示数量的差异;评价仿真开颅手术重组图像显示脑膜瘤-大脑浅静脉关系的能力;对影响仿真开颅手术重组效果的脑膜强化与否、肿瘤大小和位置等因素采用Wilcoxon符号秩和检验进行分析.结果 仿真开颅手术和3D CE-MRV显示脑膜瘤周围大脑浅静脉分别为(4.4±1.9)和(5.1±2.7)支,差异有统计学意义(t=3.131,P＜0.05).仿真开颅手术能清楚显示脑膜瘤与大脑浅静脉关系,总平均得分为(2.5±0.7)分.有脑膜强化(12例)和无明显脑膜强化(37例)患者的主观评分分别为(1.5±0.5)、(2.8±0.3)分,无脑膜强化的图像质量明显优于有脑膜强化(Z＝-3.093,P＜0.05);小脑膜瘤组(31例)和大脑膜瘤组(18例)的主观评分分别为(2.7±0.5)、(2.2±0.9)分,小脑膜瘤组明显优于大脑膜瘤组(Z=-2.057,P＜0.05);窦镰组(39例)和凸面组(10例)主观评分分别为(2.6±0.6)、(2.2±0.9)分,两组间差异无统计学意义(Z=-0.604,P＞0.05).结论 仿真开颅手术仅显示大脑浅静脉(SCVs),避免了大脑深静脉和头皮静脉的重叠,对大脑浅静脉评价更加准确;仿真开颅手术能较好地显示脑膜瘤与大脑浅静脉的关系,为脑膜瘤术前选择颅骨开窗位置、术中定位以及保护大脑浅静脉提供帮助.     

The anterior medullary–anterior pontomesencephalic venous system and its bridging veins communicating to the dural sinuses: normal anatomy and drainage routes from dural arteriovenous fistulas

Introduction  We evaluated the normal venous anatomy of the anterior medullary/anterior pontomesencephalic venous (AMV/APMV) system and bridging veins connected to the dural sinuses using magnetic resonance (MR) imaging and demonstrated cases of dural arteriovenous fistulas (DAVFs) with bridging venous drainage. Materials and methods  MR images obtained using a 3D gradient echo sequence in 70 patients without lesions affecting the deep or posterior venous channels were reviewed to evaluate the normal anatomy of the AMV/APMV system and bridging veins. MR images and digital subtraction angiography in 80 cases with intracranial or craniocervical junction DAVFs were reviewed to evaluate the bridging venous drainage from DAVFs. Results  MR images clearly revealed AMV/APMV in 35 cases. Fifteen cases showed a direct connection between AMV and APMV, while 15 cases showed an indirect communication via the transverse pontine vein or the bridging vein. In the five remaining cases, the AMV and APMV end separately to the bridging vein or the transverse pontine vein. Bridging veins were identified in 34 cases, connecting to the cavernous sinus in 33, to the suboccipital cavernous sinus in 11, and the inferior petrosal sinus in five cases. In 80 DAVF cases, seven of 40 cavernous sinus DAVFs, two craniocervical junction DAVFs, and one inferior petrosal sinus DAVF drained via bridging veins to the brain stem. Conclusion  The AMV/APMV and bridging veins showed various anatomies and frequently showed a connection to the cavernous sinus. Knowledge of the venous anatomy is helpful for the diagnosis and intravascular treatment of DAVFs.     

Detection of normal spinal veins by using susceptibility‐weighted imaging

Purpose:

To evaluate the visualization of the spinal veins using susceptibility‐weighted imaging (SWI).

Materials and Methods:

A 1.5‐T magnet equipped with a spine matrix coil was used. Axial SWI scans of 20 healthy volunteers were obtained with a three‐dimensional fast low‐angle shot (3D‐FLASH) sequence. Maximum intensity projection (MIP) of the phase images were reconstructed and five MIP images (at the levels of T11, T11/12, T12, T12/L1, and L1) were selected for the evaluation. The anterior median vein (AMV), posterior median vein (PMV), anterior radiculomedullary vein (ARV), posterior radiculomedullary vein (PRV), and sulcal vein (SV) were evaluated using a 4‐grade scale (0, none; 1, weak; 2, moderate; and 3, prominent).

Results:

The AMV was detected in all the subjects (100%). The detection rates of the other veins were lower: PMV, 65%; right ARV, 45%; left ARV, 15%; right PRV, 10%; left PRV, 30%; and SV, 0%. The average scores for AMV, PMV, right ARV, left ARV, right PRV, left PRV, and SV were 0.98, 0.24, 0.20, 0.08, 0.08, 0.14, and 0, respectively.

Conclusion:

SWI of the spine is feasible. The extrinsic spinal veins can be visualized by SWI without using contrast materials. J. Magn. Reson. Imaging 2010;31:32–38. © 2009 Wiley‐Liss, Inc.     

CT scan of dural arteriovenous fistulas

Summary CT was performed on ten cases of dural intracranial arteriovenous fistulas. There were 3 fistulas of the transverse sinus draining directly into the homolateral jugular vein; 2 fistulas of the sinus with distal occlusion of the sinus and back flow into the cortical veins (one was on the transverse sinus, the other on the sagittal sinus); 2 fistulas of the middle fossa; 3 fistulas with direct venous drainage into the cortical veins, one of these forming a tumor process in the posterior fossa. Osseous abnormalities were seen in only one case. Cerebral CT abnormalities, such as patchy or vermicular enhancement, were seen in all the cases with fistulas draining into the cerebral veins. Cerebral CT was normal in cases of fistulas of the sinus without back flow into the cerebral veins.     

The craniocervical venous system in relation to cerebral venous drainage

BACKGROUND AND PURPOSE: Passing from the supine to the upright position favors cerebral venous outflow into vertebral venous systems rather than into the internal jugular veins. We sought to determine venous connections between dural venous sinuses of the posterior cranial fossa and craniocervical vertebral venous systems. METHODS: Corrosion casts of the cranial and cervical venous system were obtained from 12 fresh human cadavers, and anatomic confirmation was made by dissection of three previously injected fresh human specimens. MR venography was performed to provide radiologic correlation. RESULTS: The lateral, posterior, and anterior condylar veins and the mastoid and occipital emissary veins were found to represent the venous connections between the dural venous sinuses of the posterior cranial fossa and the vertebral venous systems. This study revealed the nearly constant presence of the anterior condylar confluent (ACC) located on the external orifice of the canal of the hypoglossal nerve. The ACC offered multiple connections with the dural venous sinuses of the posterior cranial fossa, the internal jugular vein, and the vertebral venous system. All these structures were shown by MR venography. CONCLUSION: The lateral, posterior, and anterior condylar veins and the mastoid and occipital emissary veins connect the dural venous sinuses of the posterior cranial fossa with the vertebral venous systems. These connections are clinically relevant, because encephalic drainage occurs preferentially through the vertebral venous system in the upright position. The ACC is a constant anatomic structure that may play an important role in the redirection of cerebral blood in the craniocervical region.     

3.0T MR磁敏感加权成像对多发性硬化患者脑静脉的研究

目的 探讨磁敏感加权成像(SWI)在检查多发性硬化(MS)患者大脑内静脉及属支和深部髓静脉改变中的价值.方法 对43例MS患者和年龄、性别相匹配的43名健康志愿者行常规了MRI和SWI,在43例MS患者中,5例病程<0.5年,17例病程0.5-2.0年,21例病程>2.0年.SWI所得静脉图像应用MinIP处理后,南2名有经验的医师双盲法评定MS患者大脑内静脉及其主要属支和深部髓静脉的改变,并与对照组比较.统计学分析采用Kruskal Wallis H 检验和Wilcoxon秩和检验.结果 43例MS患者中,23例为活动期,20例为稳定期.(1)大脑内静脉及其主要属支评分:23例活动期、20例稳定期MS患者及43名健康志愿者分别为(1.96±0.71)、(1.25±0.44)及(3.00±0.00)分,三者间差异均有统计学意义(H=67.65,P<0.01);活动期和稳定期MS患者均较对照组降低,差异有统计学意义(Z值分别为-6.67、-7.76,P值均<0.01),而活动期与稳定期MS患者比较差异也有统计学意义(Z=-3.35,P<0.01).(2)侧脑室体旁深部髓静脉改变:38例病程>0.5年的MS患者(17例病程0.5～2.0年、20例病程>2.0年)侧脑室体旁深部髓静脉减少、变短;5例病程<0.5年的MS患者侧脑室体旁深部髓静脉增多、延长.(3)"穿通静脉"表现:23例活动期MS患者中,35个侧脑室体旁强化病灶内"穿通静脉"明显扩张、延长;20例稳定期MS患者中,80个侧脑室体旁末强化病灶内"穿通静脉"变细、变短,但在3例患者中,6个侧脑室体旁未强化病灶内"穿通静脉"扩张、延长.结论 SWI能显示MS患者人脑内静脉及其属支和深部髓静脉改变,对了解MS的发病机制及病理改变具有重要价值.

Abstract：

Objective To explore the value of susceptibility weighted imaging (SWI) in detecting the changes of cerebral internal veins and their tributaries.especially the deep medullary veins,in the patients with multiple sclerosis(MS).Methods Conventional MRI and SWI were performed in 43 MS patients and 43 healthy volunteers(control group).Two groups were matched on gender and age.In the MS patients.the course of disease was less than 0.5 year in 5 paticnts,between 0.5 year and 2.0 years in 17 patients and more than 2.0 years in 21 patients.SWI venograms were obtained by performing minimum intensity projection(MinIP)reconstruction.Comparing with the control group,the changes of the cerebral internal veins,their main tributaries and the deep medullar veins in the MS patients were evaluated by 2 experienced radiologists with double blind methods.Kruskal Wallis H analysis and Wilcoxon rank test were used for statistics.Results In the 43 patients,23 had active MS(active group),20 had chronic MS (chronic group).(1)The mean score of the cerebral internal veins and their main tributaries was(1.96±0.71)for 23 active MS patients,(1.25±0.44)for 20 chronic MS patients and(3.00±0.00)for the control group,respectively.There were significant differences among the three groups(H=67.65,P<0.01).And the mean scores in the active and chronic MS patients were lower than that in the control group (1.96±0.71 vs 3.00±0.00,Z=-6.67.P<0.01:1.25±0.44 vs 3.00±0.00,Z=-7.76,P<0.01),the mean score in the active MS patients was higher than that in the chronic MS patients(Z=-3.35,P<0.01).(2)The deep medullar veins were shortened or diminished in 38 MS patients whose course of disease were more than 0. 5 year, and increased and prolonged in 5 MS patients whose course of disease were less than 0.5 year. (3) The " penetrating veins " were dilated and prolonged in 35 periventricular enhanced lesions in the 23 active MS patients, and thin and short in 80 periventricular non-enhanced lesions in the 20 chronic MS patients. However, in 3 chronic MS patients, slightly expanded and prolonged "penetrating veins" were detected in 6 periventricular non-enhanced lesions. Conclusion SWI can reveal the changes of the cerebral internal veins and their tributaries, especially the deep medullary veins, in different stages of MS patients, providing important information for pathogenesis and pathological study for MS patients.     

Application of susceptibility weighted imaging (SWI) for evaluation of draining veins of arteriovenous malformation: utility of magnitude images

Introduction

The current study evaluated the signal characteristics of susceptibility weighted imaging (SWI) of arteriovenous malformation (AVM), especially for draining veins. For this purpose, we identified the draining veins of the AVM on angiography and evaluated the signal on magnitude image for SWI (SWI-mag) and minimum intensity projection image (SWI-minIP).

Methods

Subjects were 14 cases with angiographically proven AVM. SWI-mag, SWI-minIP, and time-of-flight (TOF) magnetic resonance angiography were acquired. For the draining veins of the AVM identified on angiography, we analyzed signal intensity on the images listed above, and classified it into hyperintensity (hyper), mixed intensity (mixed), hypointensity (hypo), and no visualization.

Results

On the analysis of 27 angiographically proven draining veins, 19 draining veins were classified as hyper, 3 as mixed, 0 as hypo, and 6 as no visualization on SWI-mag. On TOF images, 21 draining veins were classified as hyper, 2 as mixed, 0 as hypo, and 4 as no visualization, while 6 draining veins did not show hyperintensity on TOF, and SWI-mag visualized 3 of these 6 veins as hyper.

Conclusion

SWI-mag depicted most draining veins of AVM as hyperintensity. We speculate that this is mainly due to the higher concentration of oxygenated hemoglobin (oxy-Hb) and inflow effect of the draining vein. SWI-mag seems to be useful in the analysis and follow-up for AVM as the signal on the image may reflect physiological status.