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     

脑动静脉畸形的MRA初步研究

目的：分析脑ＡＶＭ３Ｄ－ＴＯＦ及３Ｄ－ＰＣ法ＭＲＡ表现,探讨其诊断意义。材料和方法：使用美国ＧＥＳｉｇｎａ１．５ＴＭＲ超导扫描仪对１４例患者分别行ＳＥ序列,３Ｄ－ＴＯＦ及３Ｄ－ＰＣＭＲＡ检查。结果：１４例患者ＡＶＭ位于颞顶叶２例,顶叶２例,颞枕叶２例,顶枕叶１例,枕叶３例,额叶３例,脑干１例;供血动脉来自大脑中Ａ５例,大脑前Ａ３例,大脑后Ａ１例,联合供血５例;引流Ｖ中６例引流入大脑深Ｖ,２例引流入乙状窦。结论：ＭＲＡ能准确显示畸形血管团及异常供血Ａ、引流Ｖ,结合ＭＲＩ可大大提高其诊断准确率,为临床筛选及术后随诊的首选方法。     

烟雾病的磁共振成像诊断

目的：回顾分析８例烟雾病的磁共振成像表现，探讨磁共振成像对烟雾病的诊断价值。方法：８例烟雾病中男女各４例。年龄４～４９岁，平均２０．４岁。磁共振成像应用Ｓｉｅｍｅｎｓ１．０ＴＭＲ系统和头表面线圈。均有ＳＥ序列Ｔ１ＷＩ和Ｔ２ＷＩ，７例有三维时间飞跃法磁共振血管造影（３Ｄ－ＴＯＦＭＲＡ），１例有ＤＳＡ。结果：ＳＥ序列ＭＲＩ均见丘脑－基底节区（单侧２例，双侧６例）有扩张的烟雾血管，其中以Ｔ１ＷＩ显示更为清楚直观。７例３Ｄ－ＴＯＦＭＲＡ和１例ＤＳＡ均见ＩＣＡ上端、ＭＣＡ和ＡＣＡ近端闭塞以及丘脑－基底节区的烟雾血管。这些病理血管分布侧别与ＳＥ序列磁共振成像所见一致。结论：ＳＥ序列磁共振成像和３Ｄ－ＴＯＦＭＲＡ是诊断烟雾病的有效方法。Ｔ１ＷＩ显示丘脑－基底节区烟雾血管优于Ｔ２ＷＩ。３Ｄ－ＴＯＦＭＲＡ尚适用于烟雾病血管旁路术后随诊及其高危人群普查。     

Moyamoya病的MRI和MRA诊断(附15例报告)

探讨ＭＲＩ和ＭＲＡ对Ｍｏｙａｍｏｙａ病的诊断价值。材料与方法；１５例Ｍｏｙａｍｏｙａ病患者中男６例，女９例。年龄４－４９岁２０岁以下者１１例。应用 Ｓｉｅｍｅｒｎｓ １．０Ｔ超导型ＭＲ系统行ＳＥ序列ＭＲＩ和三维时间飞跃法ＭＲＡ。均有ＳＥ序列Ｔ１Ｗ１和Ｔ２ＷＩ，１４例有３Ｄ－ＴＯＦ ＭＲＡ，１例有ＤＳＡ，６例有平扫ＣＴ。     

脑静脉血管瘤的MRI及MRA

目的：探讨颅内静脉血管瘤的ＭＲＩ和ＭＲＡ影像学表现及诊断和鉴别诊断。材料和方法：应用ＳｉｅｍｅｎｓＭｅｇｎｅｔｉｏｎＶｉｓｉｏｎ１．５Ｔ超导系统对诊断静脉血管瘤（ＶＡ）２０例进行分析。ＭＲＩ扫描用ＳＥＴ１和ＴｕｒｂｏＳＥＴ２加权序列。ＭＲＡ采用ｔｏｆ－ｔｉ３Ｄ－ｍｕｌｔｉ－ｓｌａｂ－ｔｒａ－ｔｕｎ序列。１６例作增强Ｔ１加权及ＭＲＡ检查。血管重建采用ＭＩＰ技术。有１１例曾行ＣＴ检查，１例行手术治疗。结果：所有病例均由ＭＲ检查作出首诊。Ｔ１加权１８例显示扩张引流静脉呈点条状低信号影，有２例未显示，经增强后显示，并有部分髓静脉显示。Ｔ２加权引流静脉多呈高信号，个别呈低信号。较大的ＶＡ亦可显示髓质静脉。ＭＲＡ１５例显示异常血管，典型的表现为脑实质内见为数不等的髓质静脉呈伞状汇入一根异常扩张的引流静脉，整个形态似“水母头”。１例ＭＲＡ未显示病灶。结论：ＭＲ是诊断ＶＡ最好的影像方法，ＭＲＡ有助于确诊本病。增强ＭＲＩ及ＭＲＡ可提高ＶＡ的检出率     

获得性胸主动脉病变的MRI诊断

目的：评价ＭＲＩ对获得性胸主动脉病变的诊断价值。材料和方法：共３０例,２１例在ＧＥＶｅｃｔｒａ０．５Ｔ上行ＳＥ和ＣｉｎｅＭＲＩ检查,９例在ＧＥＳｉｇｎａ１．５Ｔ上行ＳＥ、ＣｉｎｅＭＲＩ、ＧａｔｅｄＴＯＦ和３Ｄ动态增强ＭＲＡ检查。成像采用横断面、主动脉长轴和左室长轴观,部分加扫矢状面和冠状面。结果：共发现升主动脉瘤１０例、主动脉夹层１０例、主动脉扩张９例和降主动脉溃疡１例。经对照表明ＣｉｎｅＭＲＩ对合并的瓣膜病变、夹层真假腔、血栓和瘤内异常血流方式的显示较ＳＥ为佳,而ＧａｔｅｄＴＯＦ和３Ｄ动态增强ＭＲＡ对整个胸主动脉形态及头臂血管的显示最佳。结论：多种ＭＲＩ技术综合运用诊断获得性胸主动脉病变可基本达到心血管造影效果。     

磁共振成像在主动脉疾病中的应用(附29例分析)

目的：评价ＭＲＩＳＥ序列，梯度回波（ＧＲＥ）及磁共振血管成像（ＭＲＡ）对主动脉疾病的诊断价值。材料和方法：２９例主动脉疾患，其中主动脉夹层２１例，胸、腹主动脉瘤８例。全部病例采用ＭＲＩＳＥ常规序列及ＧＲＥ技术，４例行ＭＲＡ检查。结果：在ＳＥ及ＧＲＥ序列上２１例胸、腹主动脉夹层均显示真假两腔，其内膜片分别为１９和２１例。破口分别为５和８例。ＭＲＩ及ＭＲＡ能清晰地显示主动脉瘤和瘤体内结构。结论：ＭＲＩ对主动脉疾患具有肯定的诊断价值。以常规ＳＥ序列为基础，辅以ＧＲＥ及ＭＲＡ技术将能对主动脉疾病提供更多的诊断信息。     

MR T_1WI抑脂及MR胰胆管造影术用于梗阻性黄疸的诊断

目的：探讨Ｔ１ＷＩ抑脂技术（ＦＴ１ＷＩ）和ＭＲ胰胆管造影术（ＭＲＣＰ）对梗阻性黄疸的诊断价值。方法：回顾４７例不同病因所致梗阻性黄疸的ＭＲＩ征象。应用ＧＥＳｉｇｎａ１．５Ｔ超导ＭＲ机,除常规的Ｔ１ＷＩ、Ｔ２ＷＩ序列外,还采用ＦＴ１ＷＩ和ＦＭＰＳＰＧＲ造影增强及ＭＲＣＰ技术。结果：恶性病变均可见大小不等的肿块,ＦＴ１ＷＩ序列对肿块的显示最清楚,为明显的低信号。良性病变均无肿块。ＭＲＣＰ可以明确梗阻的部位及阻塞端的形态。结论：根据ＭＲＣＰ所示胆道梗阻的部位和形态,结合轴位各序列,尤其是ＦＴ１ＷＩ显示的病灶特点,能更加准确地诊断梗阻性黄疸的病因。     

正常胰腺快速MR成像序列的比较研究

目的选择最适当的胰腺快速ＭＲ成像序列。材料与方法对２０例胰腺正常者行六种快速ＭＲ成像序列检查,其中包括四种快速自旋回波序列（ＴＳＥ—Ｔ１ＷＩ、Ｔ１ＦＳ、Ｔ２ＷＩ、Ｔ２ＦＳ）和二种梯度回波序列（ＧＲＥ—ＴＦＥ、ＦＦＥ）,然后对所得图像进行定量、定性分析。结果定量分析表明,Ｔ１ＦＳ有最高的胰腺信噪比。定性分析表明,Ｔ１ＷＩ显示脾静脉最好,且能同时清楚显示肠系膜上血管、门静脉和腹腔动脉。Ｔ１ＦＳ的伪影最少,且能同时清楚显示胰——十二指肠分界、胰一胃分界及肠系膜上静脉。Ｔ２ＷＩ的图像质量及对胰一十二指肠分界显示最好,且能同时清楚显示胆总管、肠系膜上血管、门静脉和腹腔动脉。Ｔ２ＦＳ显示胆总管最好,显示胰一十二指肠分界的能力同Ｔ２ＷＩ,同时能清楚显示门静脉。ＴＦＥ和ＦＦＥ无明显的优点。六个序列中任何一个,均不能使正常胰管成像。结论在正常胰腺快速ＭＲ成像序列中,Ｔ１ＦＳ和Ｔ２ＷＩ优于其它序列。     

主动脉夹层几种磁共振影像的评价和比较

目的：评价和比较ＭＲＩＳＥ常规序列、电影（ｃｉｎｅ）ＭＲＩ及ＭＲ血管造影（ＭＲＡ）对主动脉夹层的诊断价值。材料和方法：对２５例主动脉夹层进行了３１人次ＭＲ检查。其中包括胸腹主动脉ＳＥ序列３１人次，胸主动脉ｃｉｎｅＭＲＩ２３人次及腹主动脉二维时间飞跃（２ＤＴＯＦ）ＭＲＡ２１人次。将ｃｉｎｅＭＲＩ及ＭＲＡ分别与其相应ＳＥ序列ＭＲ表现进行比较。结果：胸主动脉ｃｉｎｅＭＲＩ２３例与相应ＳＥ序列比较，两者所有病例均显示内膜片及真假两腔，但显示破口分别为１４和９例。显示头臂血管受累分别为７和２条。腹主动脉ＭＲＡ２１例与相应ＳＥ序列比较，两者均显示内膜片和真假两腔，但显示破口或再破口者分别为４和２例，腹主动脉分支血管受累分别为３９和１４条。结论：ＭＲ是诊断主动脉夹层的最佳影像学方法之一。在常规ＳＥ序列基础上，辅以ｃｉｎｅＭＲＩ和ＭＲＡ技术将大大提高ＭＲ总体观察夹层范围、内膜破口以及分支受累的能力，给临床提供更多的信息。     

蛛网膜下腔出血患者的MRA和DSA的对照研究

目的：研究ＭＲ血管造影（ＭＲＡ）在蛛网膜下腔出血（ＳＡＨ）患者病因诊断中的应用准确性和可靠性。材料和方法：回顾性分析３３例ＳＡＨ患者的ＭＲＡ资料，并与ＤＳＡ作了对比分析，ＭＲＡ采用三维时间流逝（３Ｄ－ＴＯＦ）法。结果：ＭＲＡ上显示了２６例血管病变中的２２例，包括１５个动脉瘤中的１３个，８例动静脉畸形中的６例和３例血管狭窄闭塞性病变。１个完全血栓形成的右颈内动脉瘤ＭＲＡ上未显示。但常规ＭＲＩ和ＭＲＡ原始图像上显示，ＭＲＡ结合ＭＲＩ和ＭＲＡ原始图像可以对９１％的患者做出正确诊断和评价，动脉瘤和周围血管的关系及ＡＶＭ的供血动脉和畸形结节能在ＭＲＡ上被准确评价。结论：作为一种非损伤性的血管成像方法，ＭＲＡ具有安全、可靠和方便的优点，可以做为常规用于ＳＡＨ患者的筛选检查。     

磁共振成像和磁共振血管造影对脑动静脉畸形的诊断评价

目的 探讨MRI和MRA,尤其后者对脑动静脉畸形（AVM）诊断价值和限度。材料与方法,对16例AVM者行MRI和MRA检查并与DSA进行对照研究,分别观察供血动脉,血管巢和引流静脉情况。结果 与DSA对照,显示供血动脉,MRA与其无显著差异（P＞0．05）,MRI有其极显著差异（P＜0．001）;血管巢大小,MRI,MRA与其均无显著差异（P＞0．05）,引流静脉,MRI与其有显著差异（P＜0．001）。结论 MRA与MRI联合应用可准确显示供血动脉,血管巢和部分引流静脉,是一种评价AVM血管内治疗,手术切除或立体定向放疗及效果观察的有效无创性检查方法。随着MRA新技术的不断开发,完善,将部分取代有创性DSA检查。     

Cerebrovascular pathology. Comparison of magnetic resonance and magnetic resonance angiography]

After making the visualization of the intracranial circulation possible without contrast media, the radiologist is now evaluating the diagnostic role of the different techniques of MRA. Attempts are also being made to characterize the main patterns of intracranial vascular diseases. The authors examined, with 3D TOF MRA, 40 patients presenting with 50 vascular lesions on MRI scans. Twenty of 40 patients were also studied with angiography. Seventeen aneurysms were detected, together with 3 stenoses of the cerebral arteries, 13 arteriovenous malformations, 12 dolichobasilar arteries, 3 postoperative and 2 post-embolization controls. MRI was performed with a superconductive magnet (1.5 T), a dedicated coil and gradient-echo 3D TOF FT sequences. The refocused sequence for flux, FISP 3DFT, required the following parameters: TR = 0.04 s, TE = 10 ms, flip angle = 15 degrees, 256 x 256 matrix, 1 acquisition. The 64-80 mm volume along the axial plane was divided so that an actual 1-mm thickness was excited. In post-processing, the maximum-intensity projection was employed on the axial plane 0 degrees-90 degrees (15 degrees interval). In the various conditions, the results obtained with MRA were correlated and compared with MRI findings. MRA provided useful additional information in 27.4% of cases in the study of aneurysms, arteriovenous malformations, vascular occlusion and dolichobasilar arteries, as well as in the follow-up of these lesions. MRA is currently suggested in the evaluation of cerebral circulation and is considered a complementary technique to MRI. MRA is also to be used preliminary to angiography.     

Intracranial artery dissections: serial evaluation with MR imaging,MR angiography,and source images of MR angiography

BACKGROUND AND PURPOSE: To assess chronological change in intracranial artery dissections with magnetic resonance imaging (MRI), MR angiography (MRA), and source images of MRA, and to determine whether the source images of MRA provide additional useful information to the combined evaluation of MRI and MRA. MATERIALS AND METHODS: Seven consecutive patients with intracranial artery dissections who were diagnosed by clinical history and conventional angiography were followed sequentially with MRI and MRA (mean follow-up duration, 8.8 months). Two observers independently reviewed the signal intensity of the arterial wall on T1-weighted images, luminal structures on MRA, and source images of MRA. RESULTS: In three (43%) of seven patients, the affected arterial wall had high signal intensity area from 4 to 62 days after onset on T-weighted images. Double lumen on MRA wasobserved only in one patient during the course of the study, whereas a definite low-intensity linear area in the lumen on source images of MRA was seen from 0 to 773 days after onset in all patients. When information from the source images of MRA was added to evaluation with both MRI and MRA, detectability increased to 100% from day 0 to day 3 and 67% from day 4 to day 30. CONCLUSION: The signal intensity of the dissected wall and the luminal structures on MRA and its source images vary according to chronological age. The use of source images from MRA in addition to the combined evaluation of MRI and MRA may provide more accurate diagnosis and follow-up study of intracranial artery dissections.     

MRA在诊断颅内动脉瘤中的应用

目的：研究MRA诊断颅内动脉瘤的原理与方法，优势与不足以及临床价值。方法：选择经DSA证实为颅内动脉瘤的息者30例，行三维MRA及MRI检查，全部病例均经手术证实。结果：MRA对颅内动脉瘤的敏感性为90％，结合原始断层图像和MRI，敏感性则高达97％，较准确显示了3mm以上动脉瘤的形态、大小及与载瘤动脉的关系。对于检测血栓性动脉瘤MRA优于DSA影像。结论：MRA是一种无创伤的血管检查技术．可准确显示动脉瘤。对于Willis环区动脉瘤，MRA可取代常规血管造影。     

流动伪影在颅内动脉瘤MRI诊断中的价值

目的 评价流动伪影对颅内动脉瘤的诊断价值。资料与方法 搜集经DSA(10例)或手术(5例)证实的15例同时合并有流动伪影的颅内动脉瘤的MRI和MRA资料进行回顾分析。使用Siemens Impact1．0T超导型MR扫描仪。全部患者均行脑MRSE序列扫描，13例行3D TOF MRA动脉期扫描。结果 15例颅内动脉瘤共显示29个流动伪影，在所有MR序列图像上均表现为动脉瘤残腔水平的不规则条带状影，且均位于相位编码方向上。T2WI较T1WI上所显示的伪影更为粗大、明显。结论 合理地应用流动伪影有助于颅内动脉瘤的诊断和鉴别诊断。     

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。     

Comparison of magnetic resonance angiography,magnetic resonance imaging and conventional angiography in cerebral arteriovenous malformation

Summary 10 patients with an AVM of the brain were examined by magnetic resonance angiography (MRA), magnetic resonance imaging (MRI) and conventional cerebral angiography (CCA). From MRA in 7/10 patients important information about vascular supply could be provided; in 3 patients, all with small AVM's it could be only suspected. CCA revealed the vascularisation of the AVM's in all patients and showed additional hemodynamic aspects better than MRA. With MRI in all cases the AVM could be diagnosed, but only the involvement of the main cerebral vessels could be demonstrated; however, MRI is superior to MRA and CCA in showing the nidus and the involved brain structures.     

MR angiography of the intracranial vessels: technical aspects and clinical applications

Evaluation of the intracranial circulation provides valuable information in the diagnosis and prognosis of various intracranial abnormalities and may influence patient management. Technical advances in magnetic resonance angiography (MRA) have improved the accuracy of this technique in various clinical situations, such as aneurysms, arterial and venous steno-occlusive diseases, vascular malformations, inflammatory arterial diseases, preoperative assessment of the patency of dural sinuses, and congenital vascular abnormalities. In many centers, MRA has replaced conventional digital subtraction angiography in screening for intracranial vascular disease, because of its non-invasive and non-ionizing character. Several MRA techniques have been developed for the imaging of the intracranial vascular system, such as time-of-flight MRA (TOF MRA), phase-contrast MRA (PC MRA), and more recently contrast-enhanced MRA (CE MRA). In the evaluation of steno-occlusive disease, the three-dimensional (3D) TOF-MRA technique is recommended for arterial evaluation, and the 2D TOF or 2D PC-MRA technique for venous evaluation. For the evaluation of aneurysms and arteriovenous malformations (AVMs), we recommend the 3D CE-MRA technique, especially dynamic sequences in case of AVM. In this review, the technical aspects, limitations, and optimization of these MRA techniques will be discussed together with their indications in intracranial disease.