面神经瘤的CT和MRI诊断(附六例报告)

目的 探讨CT,MRI对面神经瘤的诊断价值,方法 回顾分析了6例经手术病理证实的面神经瘤CT,MRI表现,结果 6例面神经瘤中位于颞内段4例（迷路段1例,鼓室段2例,鼓室段＋乳突段1例）,颅,内脑池段,内听段及颞内段（迷路段＋鼓室段）1例,颞内段（鼓室段＋乳突段＿并颅外肋腺段1例,肿瘤的影像学表现与肿瘤的部位有关,CT影像上,颞内段面神经瘤显示受累段面神经管扩大,破坏;中耳腔和（或）乳突软组织肿块及膝状神经窝区内质破坏,如肿瘤扩展到中颅窝或肋腺也可一并显示,1例起源于内听道,桥脑小脑角区的面神经瘤,CT,MRI清楚地显示了桥脑小脑角区肿块,内听道扩大,迷路段面神经管扩大,以及扩展到膝状神经窝区的病灶。结论 CT和MRI能准确地描绘面神经瘤的受累情况,CT在显示骨破坏细节方面极佳,而增强MRI对肿瘤本身的显示优于CT。     

面神经瘤的影像学研究

目的：研究面神经瘤的影像学检查方法和影像学表现,提高诊断准确性。方法：10例经手术病理证实的面神经瘤均行CT检查,6例还进行MR平扫和增强扫描。回顾性分析CT表现和MRI表现,并比较CT和MRI的优缺点。结果：10例面神经瘤中6例面神经鞘瘤和4例面神经纤维瘤,8例累及面神经水平段,6例累及膝部,4例累及乳突段,2例累及迷路段,3例累及内听道段,2例累及腮腺段,1例累及脑池段。主要CT表现：面神经管扩大9例;鼓室内软组织影7例;听小骨破坏5例;乳突蜂房内软组织肿块4例。主要MRI表现：6例均表现面神经增粗,其中2例显示鼓室内=乳突内和颈静脉窝软组织肿块,2例显示鼓室内软组织肿块;3例肿块呈略长T1、略长T2信号,信号不均匀,增强后呈不均匀强化;3例肿块与面神经呈等信号,信号均匀,呈均匀强化;2例面神经瘤累及内听道段面神经,平扫未显示,增强后呈明显强化而显示。比较CT与MRI表现后,发现2例累及面神经内听道段者MRI显示而CT未显示,1例累及面神经鼓室段起始部者MRI亦显示而CT未显示;对于较小的面神经瘤,MRI能直接显示增粗的面神经本身,而CT仅显示面神经管扩大和（或）破坏。结论：CT和MRI,尤其是MR增强扫描能很好地显示面神经瘤的形态、部位、范围和内部结构,有助于定位诊断和定性诊断,为临床制订手术方案和确定手术入路提供依据。     

头颈部副神经节瘤的影像学诊断

目的:结合头颈部副神经节瘤的发生部位,分析其影像学表现和特点.材料和方法:回顾性分析23例头颈部副神经节瘤患者的影像学资料(5例鼓室球瘤,12例颈静脉球瘤,3例迷走体瘤和3例颈动脉体瘤),21例行CT检查(其中1例行动态增强检查),15例行MRI检查.结果:鼓室球瘤较小,多发生于鼓岬区;颈静脉球瘤以颈静脉孔为中心,较大的肿瘤侵犯咽旁间隙、中耳、外耳道、乳突和(或)颅内;颈动脉体瘤位于上颈部颈内外动脉分叉处,伴上述动脉明显分离移位;迷走体瘤位于咽旁颈动脉鞘区,血管移位不一.以上四类肿瘤CT平扫呈中等密度,强化显著,部分肿瘤内见强化的血管和囊性改变;MRI T1WI中低信号,强化显著,T2WI中高信号,部分肿瘤内见囊变,多数肿瘤中可见血管流空"盐和胡椒征"(鼓室球瘤和较小的颈静脉球瘤中不见).鼓室球瘤和颈静脉球瘤边缘不规则,后者侵犯咽旁间隙部分边缘光滑,骨质呈虫咬状破坏;颈动脉体瘤和迷走体瘤边缘光滑,无骨质破坏.结论:多数头颈部副神经节瘤具有特定的发生部位和特征性的CT和MRI表现,可据此确诊;发生于不同部位的肿瘤的影像学表现有所差别.     

外伤性面瘫影像表现与手术对照

目的 分析面神经(管)损伤的CT和MRI表现. 资料与方法 对外伤性面瘫患者的20侧耳进行CT检查,其中6侧耳同时行MRI检查,对照手术结果 回顾性分析影像学表现. 结果 CT显示面神经管鼓室段损伤8耳,迷路段损伤1耳,乳突段损伤1耳,前膝和鼓室段同时损伤3耳,前膝和迷路段同时损伤2耳,迷路段和鼓室段同时损伤1耳,无异常表现4耳.行MRI的6侧耳表现为面神经鼓室段损伤2耳,乳突段损伤1耳,鼓室段和乳突段同时损伤1耳,迷路段、前膝和鼓室段同时损伤2耳. 结论 CT能较准确地显示面神经管的骨折,但不能完全明确面神经损伤的范围,而MRI明确地显示面神经的损伤范围,但不能直接显示骨折本身,两者联合使用可明确诊断面神经损伤范围及骨折.     

正常颞骨斜矢状面CT扫描的解剖学表现

目的 探讨听骨,内耳骨迷路及面神经骨管等结构在CT斜矢状面的影像学表现,方法 利用自制木架固定器对63只正常耳行直接斜矢状面扫描,所得影像与尸体颞骨解剖相对照。结果 显示外耳道,上鼓室,乳突窦,听小骨,面神经管乳突段及内耳骨迷路63只耳（100％）,面神经管鼓室段42只耳（66．7％）,面神经管膝部55只耳（87．3％）,前庭导水管58只耳（92．1％）,结论 直接斜矢状面扫描是继横,冠状面扫描之后的一个重要扫描方法 对耳疾病的诊断和临床手术有重要意义。     

颞骨内面神经病变的影像学表现

目的总结分析面神经病变的影像学检查方法和表现,提高诊断准确性。资料与方法回顾性分析31例经手术病理或临床跟踪随访证实的面神经病变的CT和MRI表现,31例行MR扫描,其中28例行平扫和增强扫描,3例仅行平扫;19例行CT扫描。结果（1）面神经损伤13例,8例行CT扫描,6例显示面神经管骨折,2例表现正常;13例MRI扫描均表现为面神经增粗,其中10例增强扫描显示面神经明显强化。（2）面神经炎14例,7例行CT扫描,1例因岩尖胆脂瘤致面神经管迷路段、前膝部、鼓室段前部骨质破坏,6例面神经管未见异常;14例MRI增强扫描显示面神经节段性异常强化。（3）面神经鞘瘤4例,CT表现为受累面神经管骨质破坏和软组织肿块;MRI表现为面神经节段性增粗,呈长T1、长T2信号,信号不均匀,增强后不均匀强化。经统计学处理,MRI显示颞骨内面神经病变明显优于CT（P＜0．01）。结论HRCT可显示面神经管的异常,MRI尤其是MR增强扫描可显示面神经病变的形态、部位、范围及强化表现,有助于病变的诊断和鉴别诊断。     

面神经瘤的CT和MRI诊断

目的：研究面神经瘤的CT和MRI表现,提高对其的认识。方法：9例面神经瘤中,8例面神经鞘瘤,1例面神经纤维瘤。7例行颞骨高分辨CT扫描,2例常规扫描;6例行MRI检查,其中5例做了增强扫描。结果：本组发生在右侧5例,左侧4例;内听道1例,迷路段4例,膝状神经节6例,鼓突段（降段）6例,茎乳孔5例,腮腺3例。CT表现：面神经管扩大,膝状窝骨壁膨胀,面神经径路上有条索状或结节样软组织影。MRI表现：面神经呈结节样或条索状增粗,呈跨节段性分布,T1WI为等信号,T2WI为等或高信号;有明显强化。结论：面神经径路上出现实质性节段性肿块是面神经瘤的影像特点。MR增强扫描是一种有效的检查手段。     

儿童颞骨横纹肌肉瘤一例

患者男,5岁.2008年12月以右外耳道肿物就诊.无耳痛、溢液,自诉无听力下降.体检:右外耳道浅红色肿物,质软、无触痛,表面光滑,无出血.鼓膜不可见,乳突区无压痛.听性脑干反应(ABR):右耳反应阈60 dB.既往无中耳炎病史.CT平扫示右颞骨溶骨性骨破坏,广泛累及外耳道、乳突、鼓室、岩锥、颈内动脉管、颈静脉球(图1);MRI平扫示病变呈等T1、长T2信号,填充右外耳道、鼓室、乳突,上界紧邻右颞叶下方,下方沿颈动脉向下浸润,呈较均匀等信号,膜迷路形态、信号基本正常.     

面神经鞘瘤的CT和MRI诊断

目的 分析面神经鞘瘤的CT和MRI特征,提高对其的诊断准确率.资料与方法经手术病理证实的面神经鞘瘤患者7例,均行MSCT平扫及增强扫描并三维重组,3例同时行MR平扫及增强扫描.结果 7例中,右侧6例,左侧1例.以膝状神经节为中心(迷路段+鼓室段)4例,鼓室段1例,乳突段2例.6例为小肿瘤,直径＜1.5 cm.CT影像特点:曲面重组(CPR)显示所有肿瘤均位于面神经通路上,受累段面神经管扩大、破坏,局部软组织肿块,增强扫描明显强化.MRI影像特点:面神经通路上的软组织肿块,呈等T1、长T2信号,增强扫描明显强化.结论 MSCT CPR技术结合其增强扫描特点是诊断面神经鞘瘤的关键.     

面神经管多层螺旋CT曲面重建的测量

目的　观察及测量多层螺旋CT曲面重建的面神经管。方法　用多层螺旋CT对 40例 (80耳 )病人行颞骨轴位高分辨率CT扫描 ,在轴面及多平面重建的矢状位、冠状位上行面神经管的曲面重建。观察及测量面神经管。结果　面神经管的平均长度为 (2 9.73± 1.0 7)mm。迷路段、鼓室段及乳突段的平均长度分别为 (5 .6± 0 .74)mm、(10 .66± 0 .79)mm及 (13 .47± 1.0 1)mm。迷路段、膝状神经窝、鼓室段及乳突段的平均直径分别为 (0 .76± 0 .16)mm、2 .3 7± 0 .63 )mm、(1.0 3± 0 .16)mm及 (1.5 7± 0 .3 1)mm。第一膝及第二膝的平均角度分别为 67.0 4°± 9.41°及 114 .2 5°± 8.44°。面神经管鼓室段与外侧半规管壶腹及弓部的平均距离分别为 (0 .5 7± 0 .19)mm及 (1.5 9± 0 .61)mm。鼓室段与外侧半规管成角 10 .63°± 3 .6°。面神经管鼓室段与矢状面平均成角为 3 4.65°± 5 .3 9°。 80耳中 89%可见面神经管的裂缺 ,73 .7%仅位于鼓室段 ,其余 2 6.3 %在鼓室段、乳突段均可见裂缺。结论　面神经管的多层螺旋CT曲面重建是研究面神经管CT解剖的良好影像学方法 ,结合颞骨高分辨率CT的轴面扫描及面神经管的多平面重建 ,能获得更多的信息。     

MR imaging of the intraparotid facial nerve: normal anatomy and pathology

Three normal volunteers, 58 normal patients, and three patients with parotid tumors were studied with a 0.3 T permanent-magnet imaging system to directly image the intraparotid facial nerve. On T1-weighted images the nerve appeared as a curvilinear structure of relatively low signal intensity within the fatty, high-signal parotid parenchyma. Its major divisions and branches could be imaged only with specially angled axial scan planes. To verify our observations MR imaging was compared with whole-organ cryomicrotome sections cut at the same angles. Normal variations in the appearance of the nerve and pitfalls in its visualization are discussed. Three cases of parotid tumors, with surgical confirmation of the relationship of the facial nerve to the tumor, are presented. MR is the only imaging technique capable of direct imaging of the facial nerve in the parotid bed: it may assist materially in the surgical management of tumors of the parotid gland.     

Facial nerve palsy: evaluation by contrast-enhanced MR imaging

AIM: The purpose of this study was to investigate the value of contrast-enhanced magnetic resonance (MR) imaging in patients with peripheral facial nerve palsy. MATERIALS AND METHODS: MR imaging was performed in 147 patients with facial nerve palsy, using a 1.0 T unit. All of 147 patients were evaluated by contrast-enhanced MR imaging and the pattern of enhancement was compared with that in 300 control subjects evaluated for suspected acoustic neurinoma. RESULTS: The intrameatal and labyrinthine segments of the normal facial nerve did not show enhancement, whereas enhancement of the distal intrameatal segment and the labyrinthine segment was respectively found in 67% and 43% of patients with Bell's palsy. The geniculate ganglion or the tympanic-mastoid segment was enhanced in 21% of normal controls versus 91% of patients with Bell's palsy. Abnormal enhancement of the non-paralyzed facial nerve was found in a patient with bilateral temporal bone fracture. CONCLUSION: Enhancement of the distal intrameatal and labyrinthine segments is specific for facial nerve palsy. Contrast-enhanced MR imaging can reveal inflammatory facial nerve lesions and traumatic nerve injury, including clinically silent damage in trauma.     

原发性面神经瘤的CT诊断与鉴别诊断(附13例分析)

目的:探讨原发性面神经瘤CT诊断及鉴别诊断价值。方法:搜集临床资料完整的原发性面神经瘤13例,每例患者均经手术病理证实。结果:共发现病灶15处,2例面神经瘤位于颅内桥小脑角区(CPA),面神经管内9例,2例位于腮腺实质内,其中多发病灶者2例病灶均位于乳突段和腮腺实质内。结论:CT检查对原发性面神经瘤的诊断及鉴别诊断有较大价值。     

Preoperative facial muscle imaging predicts final facial function after facial nerve grafting

BACKGROUND AND PURPOSE: Our goal was to determine whether preoperative MR imaging of facial muscles predicts facial function after facial nerve grafting. METHODS: A retrospective review of all patients undergoing facial nerve grafting between 1997 and 2001 revealed 26 patients. Twelve of the patients had adequate preoperative MR images available for review and had undergone clinical follow-up for at least 12 months. Eight had malignant parotid tumors, and four had benign skull base or parotid tumors. Preoperative facial muscle MR imaging appearance was categorized as symmetrical or asymmetrical. The asymmetrical images were further classified into mild or pronounced asymmetry. Preoperative facial function was classified by using the House-Brackmann scale. Postoperative function was graded with the May scale. RESULTS: Four patients had symmetrical facial muscles shown by preoperative MR imaging, three had mild asymmetry, and five had pronounced asymmetry. No or mild asymmetry had an 86% positive predictive value for good to excellent functional outcome. Eighty percent of patients with pronounced asymmetry experienced poor functional outcomes. Six of eight patients with malignant and perineural tumors at surgery had asymmetrical facial muscles revealed by preoperative MR imaging studies. CONCLUSION: Symmetrical or mildly asymmetrical facial muscles are predictive of good facial function after nerve grafting. Pronounced asymmetry of facial muscles on MR images is predictive of poor facial function after grafting. Asymmetric facial muscles on preoperative MR images are associated with perineural tumor spread in patients with malignant disease.     

3 T MR三维稳态进动快速成像序列显示腮腺肿瘤及其与腮腺内面神经和腮腺导管的关系

目的 探讨3 T MR三维稳态进动快速成像(3D-FIESTA)序列显示腮腺良性肿瘤及其与腮腺内面神经和腮腺导管关系的价值.方法 对22例腮腺良性肿瘤患者采用8通道头部线圈行3T常规MR序列T_1 WI、T_2 WI及3D-FIESTA序列扫描,并进行图像后处理.腮腺良性肿瘤与腮腺内面神经和腮腺导管的关系与手术结果相对照.结果 不同类型的腮腺良性肿瘤3 T MRI表现具有各自的特点.22例腮腺肿瘤在T_1WI主显示为低信号,在T_2WI上为高信号,其显示结果分别为21、22例;3D-FIESTA序列上则根据腮腺肿瘤类型的不同表现为低信号(10例)或高信号(12例)为主.腮腺内面神经主要分支在T_1WI、T_2WI及3D-FIESTA序列图像均显示为线样低信号结构,T_1、T_2WI对面神经主干的显示分别为16、18例;而3D-FIESTA对面神经主干、颞面支、颈面支的显示分别为22、21、22例.腮腺导管及其主要分支在T_1WI上呈线条低信号,T_2WI及3D-FIESTA序列图像显示为条状高信号结构,其显示分别为14、20、22例.与手术结果相对照,腮腺内面神经主干的显示结果为22例;腮腺主导管20例与3D-FIESTA序列的显示情况相一致,另2例因肿瘤推压移位,手术解剖未发现.结论 3 T MR 3D-FIESTA序列可以正确显示腮腺内面神经和腮腺导管及其与腮腺肿瘤的关系,对腮腺肿瘤手术计划的制定有重要的应用价值.     

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。     

颅骨骨巨细胞瘤的影像诊断

目的 探讨颅骨骨巨细胞瘤(GCT)的CT、MRI征象, 提高对本病的认识.方法 回顾性分析经手术病理证实的5例颅骨GCT的CT、MRI表现, 5例患者均行普通CT平扫,2例行CT增强扫描;3例以颞骨破坏为主的病例,均行颞骨MRI平扫、增强扫描及HRCT扫描及听骨链、面神经计算机重建.结果 5例均单侧发病, 右侧4例、 左侧1例.CT平扫显示广泛的膨胀性骨质破坏、残存骨嵴及骨包壳.肿瘤信号多变,在T1WI呈低-等信号;在T2WI肿瘤呈不均匀的高信号,病灶周边T2WI呈现特征性的低信号,增强扫描:实性部分表现为不均匀强化.结论 颅骨GCT的CT平扫显示广泛的膨胀性骨质破坏不伴硬化边、残存骨嵴及骨包壳,T2WI病灶周边低信号是本病的特征性影像学表现;颞骨HRCT扫描及听骨链、面神经CPR重建为术前评估听小骨、面神经受累情况,为临床制定治疗策略提供更准确的影像信息.     

Intratemporal vascular tumors: detection with CT and MR imaging

The diagnostic contributions of computed tomography (CT) and magnetic resonance (MR) imaging were compared in 12 patients with benign intratemporal vascular tumors (hemangioma or vascular malformation). The tumors included six in the internal acoustic canal and six in the geniculate ganglion region. Clinical and histologic correlations were made. Two of the six patients with tumors in the internal acoustic canal underwent CT, and both required gas cisternography to show the tumor. Five patients in that group underwent MR imaging, and all five studies showed the tumor. All six patients with geniculate ganglion tumors underwent CT. Results in one study were questionable, and five showed the tumor. Five patients in this group underwent MR imaging, but the MR findings were positive in only two cases. MR imaging should therefore be performed before CT in the evaluation of facial nerve dysfunction, as it demonstrated all tumors in the internal acoustic canal and some in the geniculate ganglion region. If MR findings are negative, CT should then be performed to rule out a possible geniculate ganglion lesion.     

Traumatic facial nerve injury: A case of facial nerve avulsion at the cerebellopontine angle

Post-traumatic facial nerve paralysis is a common disease, but intracranial facial nerve injury after blunt injury has rarely been reported. We report a case of facial nerve avulsion at the cerebellopontine angle. A 23-year-old female with incomplete right-sided facial nerve palsy and facial spasms presented to our hospital. She had a history of traumatic injury, having fallen off a table and hit her head at the age of 2 years. After the accident, she developed complete right-sided facial nerve palsy and underwent conservative treatment with steroids. A magnetic resonance imaging examination performed 21 years later showed avulsion of the facial nerve at the cerebellopontine angle. Magnetic resonance imaging targeting the facial nerves might provide additional information to computed tomography in cases with poor recovery with conservative treatment.