贝尔面瘫的MRI表现及术中对照研究

目的探讨贝尔面瘫的MRI表现及诊断价值。资料与方法回顾性分析14例贝尔面瘫患者的MRI表现,并就其中8例与术中所见对照。结果 71%(10/14)患侧面神经内耳道底段强化,93%(13/14)患侧面神经迷路段强化,而健侧面神经未见此两段强化;93%(13/14)患侧面神经膝状神经节强化,43%(6/14)健侧面神经膝状神经节强化;43%(6/14)患侧面神经鼓室段强化,21%(3/14)健侧面神经鼓室段强化;79%(11/14)患侧面神经乳突段强化,71%(10/14)健侧面神经该段强化。手术8例中不同节段神经肿胀范围与MRI增强表现符合率较高。结论贝尔面瘫患者内耳道底段及迷路段的明显强化具有一定特异性和敏感性,而乳突段强化特异性最差。MR增强扫描能够客观地反映面神经的病变范围,有助于临床诊断及鉴别诊断,并且可以为面神经减压术提供重要信息。     

Ramsay Hunt综合征的MRI表现

目的　探讨RamsayHunt综合征的MRI表现及诊断价值。 方法　 5例临床确诊的单侧RamsayHunt综合征患者 ,男 3例 ,女 2例 ,年龄 2 9～ 5 4岁 ,行MR平扫及钆喷替酸葡甲胺 (Gd DTPA)增强检查 ,其中 3例增强前后对面神经颞骨内各节段分别测量信号强度。 5例均进行面神经各节段信号强度的双侧对比及增强前后对比。结果　 4例患侧面神经节段性异常强化 (双侧信号强度增强差值 >2 0或评分相差 1级或以上 ) ,1例双侧面神经强化无差别。膝状神经节 (4/ 4 )和迷路段(3/ 4 )的异常强化相对多见 ,内听道末段、鼓室段和乳突段各有 2例异常强化。结论　对于单侧患病者来说 ,只有患侧面神经节段性强化高于健侧相应节段才有诊断意义。RamsayHunt综合征较易累及迷路段和膝状神经节。Gd DTPA增强MRI能够客观地反映面神经的病变节段 ,有助于临床诊断及鉴别诊断 ,具有一定的临床实用价值。该项检查结果与临床表现的关系还需进一步研究。     

MR增强扫描在Bell面瘫患者复查中的应用

目的 纵向观察Bell面瘫患者面神经的MR强化特征变化与预后的关系。方法 本研究为纵向观察性研究，前瞻性连续纳入本院神经内科住院的26例临床诊断为单侧Bell面瘫的患者为研究对象，分别于发病3天内、1个月、3个月三次MR面神经增强扫描，根据3个月后患者面瘫恢复情况分为完全恢复组和不完全恢复组。每次MR检查对患者进行轴位T₁WI三维磁化强度预备梯度回波序列(T₁-3D-MP RAGE)增强扫描，把面神经分为用于评估强化程度的五个节段，并对各节段面神经强化程度进行1～3级的分级标识。结果 完全恢复组21例，不完全恢复组5例。发病3个月后不完全恢复组的内听道底段、迷路段、膝状神经节及鼓室段强化程度均高于完全恢复组，差异有统计学意义(P<0.05),而发病3天内和1个月后的内听道底段、迷路段、膝状神经节、鼓室段、乳突段及发病3个月后的乳突段强化程度均没有统计学差异(P>0.05)。结论 患侧面神经早期异常强化程度与患者最终预后无直接相关性，但是3个月后仍有多节段异常强化提示患者3月后甚至更远期的预后不良。     

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.     

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。     

慢性持续性面神经瘫痪T_2WI的面神经高信号灶

作者回顾性分析不可逆面神经瘫病人的MRI征象,且与恢复良好的急性面神经瘫对比,以推测T_2WI信号异常对评估预后的价值。 检查了95例面神经瘫病人,男39例,女56例,右侧49例,左侧46例,均为单侧性。年龄6～76岁。77例Bell瘫,10例Ramsay-Hunt综合征,8例外伤性面瘫。81例在2个月内完全恢     

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。     

浅析M波潜伏期及波幅变化在Bell麻痹中的意义

目的：研究面神经运动诱发电位（ M波）潜伏期及波幅对Bell麻痹的诊断价值。方法对65例Bell麻痹患者在发病10 d内进行患侧和健侧面神经M波检测,比较两侧M波潜伏期及波幅的变化,并进行M波潜伏期与波幅的相关性分析。结果面神经颧支 M 波潜伏期健患侧分别是（1.71±0.06）ms 和（1.86±0.05）ms（P ﹥0.05）,波幅健患侧分别是（4.55±0.10）μV和（3.40±0.20）μV（P﹤0.01）;颊支M波潜伏期健患侧分别是（1.92±0.08）ms和（2.17±0.09）ms（P﹤0.05）,波幅健患侧分别是（3.78±0.24）μV和（2.93±0.24）μV（P﹤0.05）。M波潜伏期与波幅相关性分析：颧支患侧r＝     

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。     

单侧突发性耳聋内耳MR水成像形态及信号分析

目的探讨单侧突发性耳聋患者内耳MR水成像的形态与信号特点。方法采用MR水成像技术检查63例单侧突发性耳聋患者的双侧内耳,观察耳蜗、前庭及3个半规管的形态;同时测量内耳迷路及同侧桥小脑角区脑脊液的信号强度,用SPSS 17.0软件行配对t检验,比较突发性耳聋患者患耳迷路信号与健耳的差异。结果63例126只内耳迷路成像良好,耳蜗及前庭无阳性表现,但10只(15.87%)患耳的多个半规管显影中断(5个外半规管、4个上半规管及1例后半规管)、边缘毛糙(1个外半规管及1个上半规管),3例(4.76%)健耳的3个半规管(2个外半规管、1个上半规管)显影中断。患耳形态学改变的阳性发生率较健侧高,χ2检验二者差异有统计学意义(P=0.041)。患侧内耳迷路与脑脊液信号强度比为1.02±0.198,健侧为1.09±0.198,患侧内耳迷路信号减低,配对t检验二者差异有统计学意义(P=0.024)。结论单侧突发性耳聋患者患耳除半规管毛糙和显影中断外,亦见迷路信号强度减低,提示突发性耳聋患者患耳迷路淋巴液成分发生了变化。     

Ramsay Hunt syndrome associated with brain stem enhancement

Postcontrast T1-weighted MR images in a patient with Ramsay Hunt syndrome showed an enhancing lesion in the region of the nucleus of the pontine facial nerve and abnormal enhancement of the intrameatal, labyrinthine, and tympanic facial nerve segments and of the geniculate ganglion, as well as enhancement of the vestibulocochlear nerve and parts of the membranous labyrinth. This enhancement most probably resulted from a primary neuritis of the intrameatal nerve trunks of the seventh and eighth cranial nerves.     

High-intensity facial nerve lesions on T2-weighted images in chronic persistent facial nerve palsy

Our aim was to estimate the value of MRI in detecting irreversibly paralysed facial nerves. We examined 95 consecutive patients with a facial nerve palsy (14 with a persistent palsy, and 81 with good recovery), using a 1.0 T unit, with T2-weighted and contrast-enhanced T1-weighted images. The geniculate ganglion and tympanic segment had gave high signal on T2-weighted images in the chronic stage of persistent palsy, but not in acute palsy. The enhancement pattern of the facial nerve in the chronic persistent facial nerve palsy is similar to that in the acute palsy with good recovery. These findings suggest that T2-weighted MRI can be used to show severely damaged facial nerves. Received: 13 December 1999 Accepted: 2 May 2000     

MR imaging for evaluation of severe facial nerve damage in patients with facial nerve palsy

PURPOSE: To evaluate the usefulness of MR imaging for the detection of severe facial nerve damage in patients with facial nerve palsy. MATERIALS AND METHODS: We retrospectively reviewed 26 consecutive patients with facial nerve palsy (13 non-responders and 13 responders). T1-weighted, T2-weighted, and postcontrast T1-weighted images were obtained in all patients. FLAIR images were also obtained in 3 non-responders. RESULTS: The geniculate ganglion, labyrinthine segment, and tympanic segment or mastoid segment showed high signal intensity on T2-weighted images in 9 of 13 non-responders, whereas high signal intensity of the nerve was only seen in 1 of 13 responders. FLAIR imaging revealed high signal intensity lesions of the distal intrameatal segment in 2 non-responders. Contrast enhancement of the facial nerve showed a similar pattern in non-responders and responders. High signal intensity lesions on T2-weighted or FLAIR images showed enhancement on postcontrast T1-weighted images. CONCLUSION: These results suggest that a high signal intensity area on T2-weighted images is a marker of severe facial nerve damage. FLAIR imaging is useful for identification of T2-prolongation in the distal intrameatal segment.     

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。     

Bell's palsy: what is the prognostic value of measurements of signal intensity increases with contrast enhancement on MRI?

Our objective was to assess the prognostic value of measurements of the degree of contrast enhancement of the intratemporal segments of the facial nerve. We prospectively obtained MRI, slice thickness <1 mm of 20 patients with a facial palsy on the first day of inpatient treatment, and measured contrast enhancement of the nerve. The data were compared with compound muscle action potential (CMAP) measurements and the clinical course. Analysis of the initial enabled differentiation of three patients whose palsy was to show no improvement from 17 whose palsy was to resolve as expected. No patient with a poor outcome showed lesser increase in signal in the internal auditory canal, pars tympanica and pars mastoidea than patients who fully recovered. In no patient who had been diagnosed on the basis of the initial MRI as having a "normal" palsy was the amplitude of the (CMAP) reduced to less than 20% that of the normal side. Measurement of contrast enhancement was thus shown to be a prognostic indicator and may provide a basis for a differential treatment of facial palsy.     

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.     

Contrast enhancement of the facial nerve on MRI: normal or pathological?

We prospectively analysed the normal contrast-enhanced MRI features of the facial nerve and determined criteria for pathological contrast enhancement. We studied 31 patients with clinically normal facial nerves with T1-weighted images before and after contrast medium. The intensity, thickness and right-left symmetry of enhancement were assessed in each segment and correlated with MRI features observed in abnormal facial nerves. Enhancement along at least one segment of the facial nerve was seen in 98 % of cases, but only within the facial canal: labyrinthine segment: 78.2 %; geniculate ganglion: 96.9 %; tympanic: 88.4 %; mastoid: 66.6 %. Marked (++) to intense (+++) enhancement was seen in the labyrinthine segment in 17.4 %, the geniculate ganglion in 36.3 %, and the tympanic (25.6 %) and mastoid (7.1 %) segments, whereas intense enhancement was only seen in the geniculate ganglion (6 %) and the tympanic segment (11.6 %). A right-left asymmetry was noted in 69 % of cases. No correlation was found between enhancement and the thickness of the nerve. No enhancement of the eighth nerve was seen. We suggest three criteria for pathological enhancement: enhancement outside the facial canal; extension of enhancement to the eighth nerve; and intense enhancement in the labyrinthine and/or mastoid segments. Accepted: 7 May 1996     

Enhancement pattern of the normal facial nerve at 3.0 T temporal MRI

The purpose of this study was to evaluate the enhancement pattern of the normal facial nerve at 3.0 T temporal MRI. We reviewed the medical records of 20 patients and evaluated 40 clinically normal facial nerves demonstrated by 3.0 T temporal MRI. The grade of enhancement of the facial nerve was visually scaled from 0 to 3. The patients comprised 11 men and 9 women, and the mean age was 39.7 years. The reasons for the MRI were sudden hearing loss (11 patients), Méniàre''s disease (6) and tinnitus (7). Temporal MR scans were obtained by fluid-attenuated inversion-recovery (FLAIR) and diffusion-weighted imaging of the brain; three-dimensional (3D) fast imaging employing steady-state acquisition (FIESTA) images of the temporal bone with a 0.77 mm thickness, and pre-contrast and contrast-enhanced 3D spoiled gradient record acquisition in the steady state (SPGR) of the temporal bone with a 1 mm thickness, were obtained with 3.0 T MR scanning. 40 nerves (100%) were visibly enhanced along at least one segment of the facial nerve. The enhanced segments included the geniculate ganglion (77.5%), tympanic segment (37.5%) and mastoid segment (100%). Even the facial nerve in the internal auditory canal (15%) and labyrinthine segments (5%) showed mild enhancement. The use of high-resolution, high signal-to-noise ratio (with 3 T MRI), thin-section contrast-enhanced 3D SPGR sequences showed enhancement of the normal facial nerve along the whole course of the nerve; however, only mild enhancement was observed in areas associated with acute neuritis, namely the canalicular and labyrinthine segment. Imaging of the facial nerve is useful for the evaluation of pathological conditions. MRI of the facial nerve is usually performed selectively in cases of peripheral facial nerve palsy in patients with an atypical presentation or delayed recovery to exclude space-occupying lesions. The gadolinium-diethylene triamine pentaacetic acid (Gd-DTPA) contrast pulse sequence is the most informative MRI procedure for evaluation of facial nerve pathology [1]. Although many studies involving MRI of normal and paralysed facial nerves have been performed [2–10], there are no reports on the enhancement pattern of normal and abnormal facial nerves with 3.0 T MR scanning. The 3.0 T MR scan provides a higher signal-to-noise ratio (SNR), which allows a higher imaging matrix, thinner slices and a shorter time for scanning [11].The purpose of this retrospective study was to evaluate the enhancement pattern of normal facial nerves, bilaterally, with 3.0 T temporal MRI.