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.     

磁共振磁敏感加权成像在脑血管性疾病中的应用价值

目的探讨磁敏感加权成像(SWI)在常见脑血管性疾病中的应用价值。资料与方法回顾性分析经临床随访及数字减影血管造影(DSA)证实的26例脑血管疾病患者的MRI资料,与常规T1WI、T2WI、T2-FLAIR序列进行比较,分析各种脑血管性疾病在SWI上的影像学表现,评价SWI在诊断脑血管性疾病中的优势。结果海绵状血管瘤8例,常规MRI检出病灶11处,SWI共发现病灶37处,病灶在SWI图上以低信号为主,部分病灶内可见点状高信号;动静脉畸形2例,SWI对动静脉畸形的血管团及引流静脉能够清晰显示,但对其供血动脉显示欠佳;静脉畸形3例,常规MRI仅显示较粗大的流空血管,SWI清晰显示周围小畸形血管。脑梗死10例,SWI显示2例急性期脑梗死灶内的微小出血灶,常规MRI无异常发现。脑血管淀粉样变性3例,SWI对其引起的微小出血灶及血肿能清晰显示。结论 SWI能够清晰显示低血流量畸形血管及微小出血灶,为MRI诊断脑血管疾病提供更加详细、准确的信息。     

3D-TOF MRA及SWI对脑血管畸形的对照研究

目的:通过分析脑动静脉畸形和海绵状血管瘤的的3D-TOF MRA及SWI磁共振表现,探讨3D-TOF MRA及SWI对脑血管畸形的诊断价值。方法:对我院收治的44例血管畸形进行高场磁共振成像,并加扫3D-TOF MRA及SWI序列,其中26例海绵状血管瘤、18例动静脉畸形。通过分析SW I和3D-TOF-MRA技术对脑血管畸形的显示情况,比较二者对脑血管畸形的检出率以及细微特征的鉴别能力等。结果:3D-TOF MRA可以清晰显示动静脉畸形的部位、大小、输入动脉的来源、输出静脉的去向等;海绵状血管瘤MRA检查均未见异常供血动脉,病灶内无异常流空信号。SWI可清晰显示海绵状血管瘤,病灶的数目及范围较常规序列增大;SWI只能显示动静脉畸形迂曲的小静脉,但不能直观显示畸形血管团的全貌及输入动脉等粗大血管的情况。结论:3D-TOF MRA技术对于AVM之类高流速低阻力的血管畸形的显示具有独特的价值,而SWI技术则对于海绵状血管瘤等小血管或低流速的血管畸形的显示具有明显的优势。     

MR磁敏感成像技术在脑部血管性病变中的应用

目的探讨MR磁敏感成像（SWI）技术在脑部血管性病变中的应用价值。方法搜集23例脑血管性病变患者，其中海绵状血管瘤7例，静脉血管畸形4例，小动静脉畸形（AVM）3例，Sturge-Weber综合征1例，静脉窦血栓形成2例及陈旧性脑梗死6例。行T1WI、T2WI、SWI序列及增强T1WI和MR血管成像（MRA）检查，计算病灶与正常对照区的校正相位值（CP），评价SWI与其他序列及MRA在显示血管性病变细节的优越性。结果病灶与正常对照区的CP值分别为-0．112±0．032及-0．013±0．004，差异有统计学意义（t=2．167，P〈0．05）。7例海绵状血管瘤，SWI能鉴别出血与血管瘤体，发现更多的小出血灶。4例静脉血管畸形，SWI能发现更多细小的髓静脉向粗大的引流静脉集中。3例小AVM，SWI较MRA更好地显示小供血动脉。1例Sturge-Weber综合征，SWI可清晰显示钙化及脑表面异常的静脉血管网。2例静脉窦血栓形成，SWI可清晰地显示深部引流静脉及脑表面静脉网广泛增粗扩张迂曲，其中1例能发现早期脑出血灶。6例陈旧性脑梗死，SWI可更好地显示病变内陈旧性出血。结论SWI对低流量血管畸形及血管瘤、多发细小出血的显示、静脉窦血栓形成后深部静脉的扩张及早期并发出血以及脑梗死并发出血等具有常规MRI及MRA检查无可比拟的优越性，并能提供病变与正常组织的相位对比改变。     

3.0T磁共振高分辨磁敏感成像在血管畸形中的应用价值

目的:探讨高分辨磁敏感成像(HR-SWI)在脑部血管畸形中的应用价值。方法:对45例脑血管畸形的患者行常规MR序列和HRSWI扫描。其中8例同时行MRA检查,31例行增强检查。结果:45例患者均在HR-SWI上清晰显示畸形血管,其中海绵状血管瘤26例,动静脉畸形5例,静脉瘤11例,Sturge-Weber综合征3例。结论:SWI显示血管畸形更清晰,明显优于常规序列,可为临床提供更多有用的信息并有助于脑血管畸形的确诊。     

SWI在脑血管疾病中的临床应用

目的 :探讨SWI在常见脑血管疾病中的应用价值。方法:分析38例脑血管疾病患者的MRI资料,其中海绵状血管瘤5例、动静脉畸形3例、出血性脑梗死18例、脑血管淀粉样变性4例、脑出血8例。与常规MRI序列进行比较,分析SWI在诊断脑血管疾病中临床价值。结果:SWI序列所观察到的海绵状血管瘤、脑血管畸形、出血性脑梗死、脑血管淀粉样变性、脑出血的数量均明显优于常规MRI序列。结论:SWI能够清晰显示畸形血管及微小出血灶,应成为脑血管疾病的常规检查序列。     

磁敏感加权成像在脑部疾病中的研究

目的探讨磁敏感加权成像（SWI）序列在诊断脑部疾病中的临床应用价值。方法回顾性分析45例经临床随访、数字减影血管造影（DSA）或手术病理证实的脑部疾病患者的磁共振成像（MRI）资料。MRI检查包括T1WI、T2WI、T2-磁共振成像液体衰减反转恢复序列（FLAIR）、SWI。分析各种疾病的影像学表现,评价SWI在诊断脑部疾病中的优劣。结果海绵状血管瘤19例,SWI检出19例,检出率100%;T1WI序列检出8例,检出率42%。动静脉畸形出血12例,SWI序列、T2-FLAIR及T2WI序列检出12例,检出率均为100%,T1WI序列检出10例,检出率83%,SWI与其他序列对比无明显差别。静脉窦血栓检出3例,SWI除检出静脉窦血栓外,还可以显示周围引流静脉。急性脑梗死6例,其中3例SWI显示有出血,常规T1WI检查序列仅1例显示。脑肿瘤5例,其中3例SWI较T1WI、T2WI更好地显示其内出血和周围引流静脉。结论SWI能够清晰显示血流缓慢的静脉血管及微小出血灶,在显示病灶的内部结构方面也有独特的优势,能发现常规MRI不能显示的信息。     

CT与MR检查在脑血管畸形诊断中的临床价值

目的 探讨CT、MRI检查在脑血管畸形诊断中的价值.方法 回顾性分析25例经临床或病理诊断的脑血管畸形CT和MRI资料,比较CT和常规MRI序列(T1 WI、T2 WI、FLAIR)、MRA及MRI磁敏感加权成像(susceptibility weighted imaging,SWI)的影像表现、检出率,判断其诊断价值.结果 25例病例中动静脉畸形16例、海绵状血管瘤7例和静脉畸形2例.16例动静脉畸形中3例CT平扫未见异常,13例CT平扫表现为边界不清的混杂密度影和迂曲扩张的血管影.而常规MRI和MRA上均可见扩张迂曲的异常血管团影.在SWI上均可见斑点状、迂曲的条状低信号影.7例海绵状血管瘤4例为单发,3例为多发,共检出病灶73个.CT平扫检出5例19个病灶.常规MRI检出51个病灶,“桑椹”状高低混杂信号及“铁环征”较具有特征性.在SWI像上检出病灶73个,其中69个为低信号,4个为以低信号为主的混杂信号.2例静脉畸形均为单发,CT平扫、常规MRI检查均无特异性表现,SWI表现为放射状异常信号影聚集,呈“水母头”征.结论 CT检查对合并急性出血、钙化的病灶敏感,但对无出血、无钙化及微出血的小病灶检出率低,定性困难.MRI常规序列结合SWI序列扫描能提供更多、更准确的信息,为诊断脑血管畸形的最佳检查方法.     

脑血管畸形在3.0T MR磁敏感加权成像中表现多样性分析

目的:探讨脑血管畸形在3.0T MR磁敏感加权成像(SWI)上表现多样性的病理生理基础.方法:回顾性分析33例具有典型影像学表现或经手术病理证实的脑血管畸形患者.其中海绵状血管瘤24例(2例合并毛细血管扩张症),动静脉畸形(AVM)5例,发育性静脉畸形(DVA)3例,Galen静脉血管畸形合并永存镰状窦1例,毛细血管扩...     

SWI在脑静脉血管畸形诊断中的价值

目的 探讨磁敏感加权成像(SWI)在诊断脑静脉血管畸形(CVM)中的特点,以提高诊断准确率.方法 回顾分析70例CVM患者的影像资料,将SWI与常规MR对比,评价SWI对CVM检出的优越性.结果 70例患者SWI均得到明确显示,T1WI发现病灶55例,T2WI发现病灶59例,常规MR呈管状或条形流空信号,且只显示明显扩张的髓静脉及增粗的引流静脉,而SWI较常规MR更敏感更清晰地显示所有扩张的髓静脉呈放射状汇入增粗的引流静脉,呈现特征性的“水母头”状表现.结论 SWI比常规MR对CVM的检出更为敏感,结合常规MR能够做出CVM的定性诊断,有利于临床治疗及预后.     

Cerebral vascular malformations: applications of magentic resonance imaging to differential diagnosis

Summary Twelve patients with cerebral vascular malformations (5 cavernous angiomas, 1 thrombosed arteriovenous malformation, and 6 venous angiomas) were studied with magnetic resonance (MR) imaging. All lesions were clearly depicted. Characteristic MR findings were obtained mainly on T2-weighted images: a markedly low intensity area was always seen. The margins of arteriovenous malformation (AVM) and venous angioma were irregular while those of cavernous angioma were smooth in all planes on T2-weighted images. Gradient-echo (GrE) pulse sequences were more sensitive than T2-weighted spin echo (SE) in lesion detection. MR imaging could play an important role in the differential diagnosis of cerebral vascular malformations.     

磁敏感加权成像在脑静脉畸形诊断中的应用

目的：探讨磁敏感加权成像（SWI）在脑静脉畸形诊断中的价值。方法：回顾性分析19例脑静脉畸形的常规MRI及SWI表现。结果：19例常规MRI均可显示引流静脉,其中9例可显示髓静脉汇入引流静脉;19例磁敏感加权成像均可清晰显示引流静脉及髓静脉,呈现特征性的＂海蛇头＂或＂蜈蚣＂征。结论：SWI较常规MRI更能清晰和精确地显示脑静脉畸形的影像特征,可作为脑静脉畸形诊断常规序列的重要补充。     

脑血管畸形的MRI及MRA诊断

目的：研究脑动静脉畸形与海绵状血管瘤的ＭＲＩ及ＭＲＡ特征，评价不同的成像方法对脑血管畸形的诊断价值。材料与方法：对２１例脑动静脉畸形及６例海绵状血管瘤分别作了常规ＭＲ成像及ＭＲ血管成像，ＭＲＩ采用ＳＥＴ１和Ｔｕｒｂｏ ＳＥ Ｔ２加权序列，ＭＲＡ采用２Ｄ－ＦＬＡＳＨ及３Ｄ－ＦＩＳＰ序列，６例海绵状血管瘤ＭＲＡ仅使用２Ｄ－ＦＬＡＳＨ序列。所有成像以环形激化头线圈在１．０Ｔ ＭＲ仪上完成。结果：Ｔ１及Ｔ     

Utility of susceptibility-weighted imaging and arterial spin perfusion imaging in pediatric brain arteriovenous shunting

Introduction

The objectives of the study are to investigate the application of susceptibility-weighted imaging (SWI) and arterial spin labeling (ASL) imaging in the assessment of shunting and the draining veins in pediatric patients with arteriovenous shunting and compare the utility of SWI and ASL with conventional MR and digital subtraction angiography (DSA).

Methods

This study is a retrospective study of 19 pediatric patients with arteriovenous shunting on brain MRI who were also evaluated with DSA. We assessed the ability of conventional MRI sequences, susceptibility magnitude images, phase-filtered SWI images, and pulsed ASL images in the detection of arteriovenous (AV) shunting, number of draining veins and drainage pathways in comparison to DSA.

Results

The mean number of detected draining veins on DSA (3.63) was significantly higher compared to SWI phase-filtered image (mean?=?2.72), susceptibility magnitude image (mean?=?2.92), ASL (mean?=?1.76) and conventional MRI (2.47) (p?p?>?0.05). ASL was the only method that correctly identified superficial and deep venous drainage in all patients. Regarding detection of shunting, ASL, SWI phase-filtered, and magnitude images demonstrated shunting in 100, 83, and 84 % of patients, respectively.

Conclusion

SWI depicts a higher number of draining vein compared to conventional MR pulse sequences. ASL is a sensitive approach in showing 100 % sensitivity in the detection of AV shunting and in the diagnosis of the pattern of venous drainage. The present findings suggest the added utility of both SWI and ASL in the assessment of AV shunting.     

磁共振成像对脑血管畸形的诊断

目的 探讨磁共振成像对脑血管畸形(cerebral vascular malformation,CVM)的诊断价值.方法 回顾性分析42例脑血管畸形的磁共振平扫、弥散加权成像(DWI)、增强扫描及其中15例的扰相梯度回波加权成像(T_2~*WI)、10例的磁共振血管成像(MRA)、5例的磁敏感加权成像(SWI)表现,分别评价其对脑血管畸形的显示价值.结果 病灶位于额叶19例,枕叶9例,颞叶6例,顶叶3例,小脑半球2例,脑干1例,环池1例,大小脑及脑干多发病灶1例,其中脑静脉畸形20例,海绵状血管瘤13例,动静脉畸形7例,脑静脉畸形合并海绵状血管瘤2例.结论 各种磁共振成像序列相结合能明确诊断脑血管畸形.     

Heterogeneity of cerebral cavernous hemangiomas diagnosed by MR imaging

The cavernous hemangioma (cavernoma) is increasingly recognized as a vascular malformation of the brain that may present with seizures, hemorrhage, or progressive neurological deficit. Since 1985 we have identified 13 cases of presumed cavernoma of the brain based on the findings on CT, selective angiography, and magnetic resonance (MR) imaging. In each case CT showed a high density lesion that was "occult" or "cryptic" on angiography. However, within all lesions MR revealed a complex internal structure consisting of reticulated patches of high and low intensity signal surrounded by a hypointense rim on T1- and T2-weighted pulse sequences. Of the nine operated cases, five resected specimens were compatible with pure arteriovenous malformations (AVMs), and the other four were mixtures of cavernoma with either AVM or venous angioma. Our experience strongly suggests that the above complex of radiographic findings is not at all specific for the cavernoma. We propose that the major common factor shared by such "cavernomatoid" malformations is low blood flow. We believe low flow lesions follow a relatively benign clinical course, and they readily lend themselves to surgical resection.     

Susceptibility-weighted angiography for the detection of high-flow intracranial vascular lesions: preliminary study

Objectives

Susceptibility-weighted magnetic resonance imaging (MRI) sequences may demonstrate various signal intensities of draining veins in cases of high-flow vascular malformation (HFVM), including arteriovenous malformation (AVM) and dural arteriovenous fistula (dAVF). Our objective was to evaluate susceptibility-weighted angiography (SWAN) for the detection of HFVM.

Methods

Fifty-eight consecutive patients with a suspected intracranial vascular malformation were explored with SWAN and post-contrast MRI sequences at 3 T. The diagnosis of slow-flow vascular malformation (SFVM), including developmental venous anomaly (DVA) or brain capillary telangiectasia (BCT), was based on MRI. Patients with suspected HFVM underwent digital subtraction angiography (DSA). SWAN images were analysed by three blinded readers according to a three-point scale of the venous signal.

Results

Thirty-one patients presented 35 SFVM (26 DVA and 9 BCT) that systematically appeared hypointense on SWAN images. In patients with atypical MRI findings, DSA revealed one patient with an atypical DVA and 26 patients with HFVM (22 AVM and 4 dAVF). SWAN revealed at least one venous hyperintensity in all patients with HFVM. Agreement between readers was excellent.

Conclusions

SWAN appears reliable for characterising blood flow dynamics in brain veins. In clinical practice, SWAN can routinely rule out HFVM in patients with atypical brain veins.

Key Points

? Susceptibility-weighted angiography (SWAN) offers new perspectives for detecting intracranial vascular malformations. ? SWAN sequence provides non-invasive characterisation of blood flow dynamics. ? SWAN can differentiate between high and slow flowing venous blood. ? SWAN can routinely rule out high-flow vascular malformations.