Magnetic resonance imaging and angiography in hemifacial spasm

Summary We used magnetic resonance imaging (MRI) and magnetic resonance angiography (MRA) to investigate 14 patients with unilateral hemifacial spasm (HS) and 20 controls. The relationship of the seventh and eighth cranial nerves to adjacent vessels was best visualized on the contiguous flow sensitive 3D-FISP images. Reconstruction of projectional MRA was helpful to assess the complex architecture of the vertebrobasilar system. Neurovascular contact in the facial nerve root exit zone was present in 4 of 20 controls and in 12 of 14 patients, in whom it predicted the affected side. These results support previous findings of surgical and electrophysiological investigations that local irriation of the facial nerve is the most possible explanation for HS. MRI and MRA provide vascular and brain tissue diagnosis in a single non-invasive examination and should be recommended as primary neuroradiological procedure in HS.     

磁共振体层血管造影在面肌痉挛病因诊断中的价值

目的 评价磁共振体层血管造影成像技术（MRTA）在面肌痉挛病因研究中的价值,方法 面肌痉挛病人共121例,均行双侧面神经多平面成像MRTA检查,其中23侧面神经随后接受了面神经微血管减压术（MVD）,结果 242侧受检面神经有面肌痉挛症状者123侧,其中MRTA检查显示面神经出脑干段（RFZ）有血管压迫者116侧,敏感性94．3％,无症状者119侧,其中MRTA检查显示REZ无血管压迫者112侧,特异性94．1％,23侧面神经接受MVD手术,有21侧术中所见与术前MRTA所示相吻合。结论 多平面成像MRTA检查方法有助于明确面肌痉挛的病因,对MVD的术前评估有重要意义。     

Three-dimensional MRI of hemifacial spasm with surgical correlation

MRI was used to investigate 100 patients with hemifacial spasm, using 3D-FT T2-weighted (CISS) and contrast-enhanced 3D-FT T1-weighted (turbo-FLASH) sequences in all cases. MR angiography was performed in 54 patients, using 3D-MT FISP images. Decompression of the facial nerve through a retromastoid craniotomy was performed in all patients. Hemifacial spasm caused by tumours in the cerebellopontine angle was not included. Vascular contact with the facial nerve root-exit zone or at the internal auditory canal was present in 96 of 100 patients with hemifacial spasm. The vessel responsible was the vertebral artery (VA) in 18 cases, the posterior inferior cerebellar artery (PICA) in 23, the anterior inferior cerebellar artery (AICA) in 22, the VA and PICA in 24, VA and AICA in 3, PICA and AICA in 1, VA, PICA and AICA in 4, and a vein in 1 case. CISS images showed compressive vascular loops better than contrast-enhanced turbo-FLASH images alone. The sensitivity of MRI was high, since only one false-negative case was found among the 100 patients who underwent surgery. Received: 10 July 1995 Accepted: 4 June 1996     

面肌痉挛的3.0T3D-TOF MRA表现分析及病因诊断

目的 探讨面肌痉挛的3.0T 3D-TOF-MRA表现及病因诊断.方法 回顾性分析48例面肌痉挛患者术前3D-TOF-MRA图像,观察血管与面神经的毗邻关系,判明责任血管,并与术中所见血管与面神经的毗邻关系进行对照分析.结果 48例患者术中均找到责任血管:术前3D-TOF-MRA判明责任血管46例(95.8％),与术中所见相一致;2例(4.2％)责任血管来源不明;面神经受压位置在神经根出脑干处(REZ)44例(91.7％),在面神经中1/3段1例(2％),在外1/3段3例(6.3％);患侧与健侧均有血管压迫者31例,邻近血管的粗细和血管是否成袢是引起面肌痉挛的主要因素,对是否产生症状具有统计学意义(P ＜0.05).结论 MRA发现有血管与面神经毗邻未必一定产生面肌痉挛的症状,只有将MRA所见责任血管与面神经的毗邻关系同临床症状相结合,才能对显微外科血管解压术(MVD)的成功实施提供重要的指导意义.     

磁共振3D-FIESTA在面肌痉挛诊断中的应用

目的 探讨MR三维稳态进动快速成像（3D-FIESTA）序列在面肌痉挛（HFS）中的诊断价值.方法 23例临床怀疑HFS的患者行3D-FIESTA序列成像并多平面重建,以临床表现为诊断标准,同时检查每一例的每一侧面神经与邻近血管关系.结果 面神经血管接触分别为真阳性20侧,假阴性3侧,假阳性11侧;真阴性12侧,3D-FIESTA诊断有无HFS的差异有统计学意义（P＜0.05）.结论 MR 3D-FIESTA序列可以清晰显示面神经与邻近血管的关系,为临床治疗提供更准确、更全面的影像学诊断依据.     

MR血管成像Hosoya评分对面肌痉挛病因诊断中血管压迫程度的量化研究

目的对面肌痉挛（hemifacial spasm，HFS）患者面神经根部血管压迫的程度进行量化研究，评价Hosoya评分在面肌痉挛病因诊断中的价值并对其进行改良。方法对20例正常人及36例偏侧面肌痉挛患者进行脑十部位三维时间飞跃法MR血管成像（3D—TOFMRA）检查，采用Hosoya评分及改良Hosoya评分对轴面、冠状面原始图像面神经根部的血管压迫进行量化评分，对改良Hosoya评分≥1．5分的27例患者进行血管减压治疗。术后复查MR血管成像（MRA），并重新进行改良Hosoya评分。结果20例正常人Hosoya评分，仅有3例为1．0分，无一例≥1．5分，判断为无血管压迫；36例HFS患者中，患侧Hosoya评分≥1．5分者27例，阳性率81．8％，按改良Hosoya评分，患侧≥1．5分者33例，阳性率91．7％；有6例小血管骑跨在面神经根部，Hosoya评分无法评价，通过改良的Hosoya评分方可确定量化；患者手术前后改良Hosoya评分经秩和（等级分组）检验，差异有统计学意义（H=27．192，P〈0．001）。结论Hosoya评分能对面肌痉挛患者面神经出脑干处的血管压迫情况进行量化，但对小血管压迫有一定局限性，改良Hosoya评分可以弥补这一缺陷。     

Three-dimensional-MRI of neurovascular compression in patients with hemifacial spasm

We prospectively studied 30 patients to assess the usefulness of three-dimensional (3D) contrastenhanced MRI in patients with hemifacial spasm. In all patients neurovascular compression of the facial nerve could be detected. Microvascular decompression was performed in 14, and vascular compression of the root exit zone of the facial nerve and the offending artery were exactyl as predicted by MRI in all but 2. We also retrospectively studied whether the symptomatic side could be defined only by enhanced 3D MRI in 55 randomised individuals (30 with and 25 without hemifacial spasm). All symptomatic sides were correctly identified, and the false-positive rate was 13.8%.     

Magnetic resonance tomographic angiography: diagnostic value in trigeminal neuralgia

A combination of MRI, MR angiography and MR tomographic angiography (MRTA) was used to study the relationship to the root exit zone of the trigeminal nerve to surrounding vascular structures in seven patients with trigeminal neuralgia (TN) and ten patients with no evidence at a lesion in this region. MRTA is the technique for showing the relationship between vessels, cranial nerves and brain stem. MRTA clearly demonstrated the presence of a vessel at the root exit zone of the trigeminal nerve in all patients with TN. In the ten other patients, examination of 20 trigeminal nerves revealed that only one nerve (5%) was in contact with a vessel at the root exit zone. This study supports vascular compression of trigeminal nerves as a cause of TN, and demonstrates the value of MRTA as noninvasive technique for demonstrating compression.     

烟雾病的MRI、MRA诊断价值

 目的探讨MRI、MRA对烟雾病(Moyamoya病)的诊断价值.方法对11例Moyamoya病患者行MRI和MRA检查,MRI包括横轴位和矢状位T1WI、T2WI、FLAIR;MRA采用3D TOF法,3例行增强MRA.结果MRI表现为:(1)Moyamoya血管:双侧3例,单侧8例;(2)脑梗死和脑软化灶11例;(3)局部脑萎缩3例.MRA表现为3例双侧颈内动脉狭窄,双侧大脑中、前动脉闭塞,大脑后动脉形成异常血管网;6例右侧颈内动脉、大脑中动脉狭窄;2例左侧颈内动脉、大脑中动脉狭窄.结论MRI能良好的显示脑内病变,MRA能较完整的显示异常血管,MRI与MRA相结合可作为烟雾病诊断的首选检查方法.     

3D-VIBE序列对血管压迫性三叉神经痛和面肌痉挛诊断价值

目的探讨3.0 T磁共振3D扰相梯度回波(3D-VIBE)序列对于三叉神经痛和面肌痉挛责任血管的诊断价值。方法利用3D-VIBE的原始图像重建,从不同的角度观察神经与血管的走行关系,发现责任血管,并与临床微血管减压术(MVD)进行比对。结果进行3D-VIBE序列扫描后发现责任血管,与术中所见基本符合。血管呈高信号,神经呈等信号,对比良好,能够直观显示血管与神经的解剖结构。三叉神经痛的症状侧的血管压迫阳性符合率为90.6%(29/32),面肌痉挛的症状侧的血管压迫阳性符合率为89.4%(17/19)。结论 3D-VIBE序列对于发现血管压迫性三叉神经痛和面肌痉挛责任血管,明确血管与神经的关系有诊断价值。     

磁共振断层血管造影诊断面肌痉挛的临床应用评估

目的 探讨磁共振断层血管造影(MRTA)以及MRTA评分诊断法对于偏侧面肌痉挛(HFS)的病因诊断价值。资料与方法 回顾性分析78例HFS患者MRI表现及手术结果。结果 MRTA评分法诊断结果显示78例HFS患者中患侧面神经出脑干段受压迫69例，其中面神经受血管压迫或与之关系密切者61例，血管对面神经有可疑压迫者7例，1例为小脑扁桃体疝压迫面神经。9例未见异常。手术结果显示面神经根部受血管压迫75例，1例为小脑扁桃体疝压迫面神经，另有2例手术未见异常。与MRTA评分法诊断结论基本一致。压迫血管为小脑前下动脉(AICA)、小脑后下动脉(PICA)、椎动脉(VA)、不知名血管。结论 多平面MRTA成像可清楚显示VA、AICA、PICA、面神经出脑干段。同时采用MRTA评分法对诊断HFS病因及制定手术方案有很大帮助。     

磁共振血管成像对血管压迫性面肌痉挛的诊断价值

目的:分析神经血管压迫性面肌痉挛患者3D-TOF MRA表现,探讨其临床诊断价值。方法:回顾性分析32例面肌痉挛患者3D-TOF MRA表现与手术结果。结果:32例面肌痉挛患者共64侧面神经,3D-TOF MRA检查发现症状侧血管压迫或接触,经统计学分析,患者症状与是否存在血管压迫或接触有显著性意义(P<0.01)。32例患者症状侧行手术治疗,术中证实均有血管压迫或接触者,3D-TOF MRA诊断血管与手术不符者6例。结论:3D-TOF MRA能清晰显示面神经与毗邻血管之间的关系,对面神经血管压迫或接触的正确诊断具有重要价值,能够为面神经显微血管减压术提供手术依据。     

Magnetic resonance imaging and angiography of the brain in embolic left atrial myxoma

Summary A case of left atrial myxoma presenting exclusively with neurological symptoms, studied with magnetic resonance imaging (MRI) combined with cerebral angiography and computed tomography (CT) is reported. Typical angiographic findings suggested the diagnosis of myxoma. MRI showed multiple ischemic lesions disseminated throughout the entire brain, some of which had been clinically asymptomatic. Because of its sensitivity in identifying small cerebral infarcts, MRI should prove in the future to be a first-choice technique in the evaluation of the presence of and extent of cerebral involvement in embolic left atrial myxoma.     

MRI在三叉神经痛和半侧面肌痉挛病因诊断中的价值

目的 探讨MRI在诊断三叉神经痛与半侧面肌痉挛中的价值.方法 将51例三叉神经痛与23例半侧面肌痉挛患者的术前MRI资料与手术结果进行对照分析.结果 ①74例患者中,MRI诊断患侧桥小脑角胆脂瘤8例,听神经瘤7例,三叉神经瘤4例,脑膜瘤3例,患侧神经微血管压迫49例(66.21％),MRI未见异常者3例(4.05％);②手术病理结果:胆脂瘤8例,听神经瘤7例,三叉神经瘤4例,脑膜瘤3例,三叉神经或面神经根部异常血管压迫者46例(62.16％),术中未见异常者6例(8.11％).结论 MRI在三叉神经痛和半侧面肌痉挛病因诊断中具有很高价值,是术前首选的检查方法.     

Magnetic resonance angiography of intracranial aneurysms: comparison with intra-arterial digital subtraction angiography

Summary Magnetic resonance angiography (MRA) with flow rephased gradient-echo sequences is a new non-invasive method for vascular imaging. We compared MRA and intra-arterial digital subtraction angiography in 18 patients with intracranial aneurysms to test whether MRA presently provides an alternative to cerebral angiography for the diagnosis of these anomalies. MRA showed 19 of the 22 aneurysms detected (86.4%). However, problems, especially with turbulent or slow flow, resulted in 6 studies (27.3%) with limited and 2 with questionable demonstration of an aneurysm, and 1 false negative study. At present, MRA is definitely inferior to angiography for the demonstration of intracranial aneurysms, due to its lower resolution and other limitations.     

Magnetic resonance angiography in meningovascular syphilis

Meningovascular neurosyphilis (MN) is an unusual cause of stroke in young adults. The clinical manifestations include prodromal symptoms weeks or months before definitive stroke. The diagnosis is based on clinical findings and examination of the serum and cerebrospinal fluid. We report a case of MN with basilar artery irregularities demonstrated by magnetic resonance angiography.     

磁共振体层血管造影对三叉神经痛诊断价值的研究

目的：探讨磁共振体层血管造影（MRTA）对三叉神经痛的诊断价值。方法：回顾性地分析120例经手术治疗的三叉神经痛患者的MRTA表现及手术结果。结果：120例症状侧MRTA检查有血管压迫者为79侧，接触者为28侧，共107侧，敏感性为89．17％。120例症状侧行手术治疗，手术发现有血管压迫或接触者76侧，MRTA检查诊断神经血管压迫和接触的特异性分别为96．2％和82．14％。结论：MRTA成像作为一项新的影像学检查技术，能较好地显示三叉神经根与周围血管之间的关系，从而为三叉神经痛的病因诊断及临床的治疗提供可靠的影像学依据。     

Magnetic resonance angiography and selective angiography following extra-intracranial bypass operations

Magnetic resonance angiography (MRA) was compared with conventional angiography in 14 patients following extra-intracranial arterial anastomosis. In 13 patients the bypass was shown by MRA and confirmed by conventional angiography. In five of these, the anastomosed vessels, in particular the superficial temporal artery, was of the same calibre or smaller than the same vessels on the contralateral, healthy side. In one patient no anastomosis could be shown by MRA, and occlusion of the bypass was confirmed by conventional angiography. Absence of dilatation of the anastomotic vessels may indicate insufficient bypass function due to stenosis or an incorrect indication for surgery.     

Magnetic resonance angiography compared to intra-arterial digital subtraction angiography in patients with subarachnoid haemorrhage

Summary In order to evaluate the sensitivity and specificity of magnetic resonance angiography (MRA) in spontaneous subarachnoid haemorrhage, 14 patients with recent haemorrhage verified by CT or lumbar puncture were investigated with both selective intra-arterial digital subtraction angiography (IA-DSA) and MRA by two independent teams, each having the same preangiographic information. The results were compared with each other and whenever possible (all positive cases except one) with those of surgical intervention. Seven patients were identified by MRA and IA-DSA as having a single aneurysm on the circle of Willis, 1 an aneurysm of the posterior inferior cerebellar artery 1 an aneurysm of the internal carotid artery (siphon) and 2 patients with two aneurysms on the circle of Willis. MRA and IA-DSA both failed to demonstrate aneurysms in 2 cases. Three patients had negative results on both methods and no surgical intervention was attempted. The aneurysms ranged from 0.3 to 1.5 cm in size. In most cases there was agreement between MRA and DSA, leading us to believe that, if the proper protocols are followed, MRA is a powerful alternative to other established methods in the detection of intracranial aneurysms. At this stage it will not replace IA-DSA prior to surgery, but the ability to obtain various projections using 3D MRA may improve surgical planning.