三叉神经痛的病因学及相关MRI研究进展

三叉神经痛(trigeminal neuralgia,TN)是颅神经病变中最常见的一种,其可能的病因、发病机制及病理变化尚未被明确统一和证实。MR融合成像技术能够更精确评估三叉神经与邻近血管的关系,更直观地指导相关手术。MR功能成像的应用对深入了解TN的发病机制及评估预后有重要意义。作者旨在对其病因学及相关的MRI研究进展作一综述。     

血管压迫性三叉神经痛的MR成像序列选择

大部分三叉神经痛是三叉神经脑池段的神经血管压迫(Neuro vascular compression,NVC)所致 [1],微血管减压术是此种原因所致三叉神经痛的有效治疗方法.影像上精确地显示三叉神经与周围血管的关系,对于血管压迫性三叉神经痛的诊断及微血管减压术至关重要.MRI是三叉神经痛的主要影像学检查方法,文献资料颇多.文献中应用最多的MR成像序列是3D FSE T2WI及TOF MRA,由于该成像序列固有的缺点,其对NVC显示的敏感性及特异性一直存在争议.     

MR对三叉神经痛病因的研究

目的 :MR扫描探讨三叉神经痛的病因。方法 :MR常规加增强扫描及三维时间飞越血管成像( 3DTOFMRA)原始图像对 45例三叉神经痛患者进行了扫描 ,盲法观察病侧三叉神经根部有无血管或肿瘤压迫 ,神经根显示的清晰度。观察结果与手术结果对照。结果 :病侧血管神经压迫 66 7% ( 30 /45 ) ,未发现病因 5例 (手术发现 2例为静脉压迫 ) ,诊断与手术符合率 88 2 % ( 15 /17)。肿瘤诊断符合率为 10 0 % ( 6/6)。除肿瘤外 ,所有行伽玛刀定位治疗者均清晰地显示了三叉神经根。结论 :三叉神经痛的病因最常见的是血管神经压迫 ,其次是肿瘤压迫。MR常规加增强扫描及 3DTOFMRA原始图像是显示两种病因的最好序列 ,3DTOFMRA原始图像对三叉神经根显示最佳 ,有利于伽玛刀治疗的准确定位     

磁共振静脉造影的血管模型应用研究

目的通过二维时间飞跃法磁共振血管造影（2D TOF MRA）技术在血管模型中的应用分析，评估其价值和限度。方法分别在不同流速、不同成像角度、不同程度狭窄与成像角度的情况下行2D TOF法MRA，测量其MR信号值。结果当液体流速为10滴／min时，其MR信号与静止液体的MR信号差异有显著性。该方法依赖于成像的角度，当成像平面接近平行时，MR信号明显减弱。狭窄程度与成像角度间亦存在协同作用。结论液体流速、成像角度与狭窄程度均对该方法有影响，该方法普遍适用于下肢静脉病变的诊断。     

磁共振成像的新近展

20年来MR成像技术在医学领域中发展相当迅速,取得了引人注目的进步。近年来其发展主要集中在功能性磁共振成像(functional magnetic rcsonance imaging, FMRI)和磁共振频谱分析(MR spectroscopy imaging, MRSI)方面。 功能性MR成像 目前功能性MR成像主要应用于探测脑的皮层功能。根据血氧依赖水平(blood oxygen level dependent, BOLD),对神经活动在不同刺激下的反应作出描述,如运动、语言、视觉或听觉信号。这些方法目前在功能性MR成像上被用于确定各种精神障碍所伴有的信号类型,如图雷特综合症(儿童期面肌     

CT/MR超声造影融合成像在肝癌消融术中的应用探讨

通过选取笔者所在医院治疗的53例肝癌病例,分别是普通超声成像和利用CT/MR超声造影融合成像技术进行引导消融,对不同的成像方法进行分析和总结。结果本研究数据显示,因普通超声清晰度欠佳而不能进行的消融术,在CT/MR超声融合成像的引导下可以进行,并且治疗效果与普通超声相比无明显差异。肝癌消融术中,普通成像与CT/MR超声融合成像均能达到引导肝癌消融术的治疗目的,但是在普通超声成像清晰度欠佳而不能进行的情况下,在CT/MR超声融合成像的引导下得以成功进行肝癌消融术,CT/MR超声融合成像在临床肝癌消融术中具有不可或缺的价值。     

MRI检查对三叉神经痛的临床诊断价值（附45例分析）

三叉神经痛是一种临床的常见病，它可以分为原发性与继发性。作通过45例三叉神经痛患的MR检查资料作回顾性分析，探讨MRI对三叉神经脑池段不同疾病所致的三叉神经痛的临床诊断价值。     

磁共振成像中表面线圈的应用研究

为进一步提高表面线圈在MR成像中的应用价值，通过对几种不同规格的线圈在标准模型上成像效果的检测，并就如何合理选择表面线圈的有关问题作了初步探讨。认为，不同机型中各类表面线圈均可根据信噪比──深度曲线以及充分权衡线圈大小、受检部位大小和深度三者间关系，制定出一套适合于各自选择表面线圈的应用规范，以确保MR成像质量。     

慢性偏头痛患者超敏性疼痛的病理生理机制研究

目的:利用血氧水平依赖(BOLD)功能核磁成像探讨慢性偏头痛患者产生皮肤超敏性疼痛(CA)的病理生理机制。方法:采用前瞻性研究方法,将研究对象分为四组。A组(n=29):伴有一侧前臂(颈8支配区)CA和/或同时有V1区和/或C2-C3区CA者;B组(n=31):伴有一侧额区(三叉神经第一支)和/或伴有一侧颈区(C2-C3支配区)CA者;C组(n=30):不伴CA者;D组(n=30):正常对照。采用BOLD功能核磁成像技术研究慢性偏头痛患者诱发CA时三叉神经感觉系统不同级别神经元激活情况。结果:在诱发CA时,A组的三叉神经节、三叉神经脊束核和丘脑的神经元均被激活致敏,B组的三叉神经节、三叉神经脊束核受到激活致敏,C组则只有三叉神经节受到激活致敏,D组则三级神经元均未激活致敏。结论:慢性偏头痛出现的头痛和躯体不同部位的CA与三叉神经感觉系统不同级别神经元受到激活致敏有关。     

磁共振成像观察宫颈癌放疗后盆部软组织变化

目的分析宫颈癌放疗中与放疗后盆部软组织、器官的异常MR表现.探讨MR成像对显示盆部软组织损伤的临床价值.方法 38例经病理证实的宫颈癌患者在放射治疗前及治疗中和治疗后不同时间段行盆腔MR扫描.在MR图像上观察盆部软组织、器官在放疗前后的大小及信号改变.结果放疗可引起多个组织、器官的异常MR表现.异常MR表现发生率在40%以上的有直肠、直肠筋膜、宫旁组织、盆壁肌肉与皮下脂肪.直肠、膀胱、子宫的异常MR表现在放疗后6个月可消失.结论 MR成像可对盆部软组织的射线损伤进行实时监测,对宫颈癌放射治疗有指导意义.     

磁共振三维稳态进动快速成像诊断原发性三叉神经痛52例分析

目的：探讨磁共振三维稳态进动快速成像（three-dimensional fast imaging employing steady state acquisition ,3D-FI-ESTA）对原发性三叉神经痛的诊断价值。方法采用磁共振3D-FIESTA序列扫描52例原发性三叉神经痛患者的三叉神经出脑干段,并做多平面重建。分析患侧组及健侧组三叉神经出脑干段与邻近血管的关系。结果患侧组与健侧组神经血管接触阳性比例分别为52/53与35/51,神经受压推移比例分别为10/53与1/51,差异有统计学意义（ P＜0.05）。结论磁共振3D-FIESTA,可以清晰显示三叉神经与邻近血管的关系,为原发性三叉神经痛的诊断及治疗提供可靠的影像学依据。     

三叉神经痛神经血管压迫的影像学评价

精确地评价三叉神经入口处神经血管压迫,对三叉神经痛患者施行微血管减压术的规划是有用的。应用界限成像融合三维磁共振脑池造影术/血管造影术能立体的显示三叉神经入口处神经血管压迫的解剖学关系,评价责任血管的存在,压迫的部位及程度。界限融合三维磁共振脑池造影术/血管造影术对三叉神经痛患者的诊断及成功地实施微血管减压术是有用的。     

神经纤维脂肪性错构瘤的MRI表现

目的 探讨神经纤维脂肪性错构瘤(FLH)的MRI表现.方法 回顾性分析2011年1月～2021年8月10例FLH的临床及MRI资料.男7例,女3例,年龄1～37岁,中位年龄21.5岁.10例患者均行MRI平扫.结果 9例累及正中神经,MRI表现为正中神经远段及分支增粗,在轴位MRI图像上,增厚的神经外膜包裹多条增粗的神...     

三叉神经痛伽玛刀治疗前MRI扫描序列研究

目的探讨伽玛刀治疗三叉神经痛MRI定位的最佳扫描序列。方法选择2004年7月-2006年3月行伽玛刀手术的原发性三叉神经痛患者60例,随机分为3组,每组各20例。伽玛刀术前上头架定位,然后对3组分别采用快速自旋回波序列（Turbo Spin Echo,TSE）、增强三维小角度激发快速梯度回波序列（enhanced three-dimensiunal fast low angle shot,enhanced3D-FLASH）、三维结构干涉稳态序列（three-dimensional constructive interferencein steady state,3D-CISS）进行扫描,观察三叉神经及周围血管的显示情况。结果①TSE扫描20例三叉神经,14例显示优,血管显示一般。②增强3D-FLASH扫描三叉神经,18例显示优,2例显示良,周围血管显示优。③3D-CISS扫描三叉神经,20例均显示优,周围血管显示良。结论 3D-CISS和增强3D-FLASH序列的融合影像能够清晰地显示三叉神经根及周围血管,有利于伽玛刀的精确定位,具有较高的临床应用价值,可以作为伽玛刀治疗原发性三叉神经痛的常规定位方法。     

Neurophysiologic and quantitative sensory testing in the diagnosis of trigeminal neuropathy and neuropathic pain

This study investigated the utility of neurophysiologic examination and thermal quantitative sensory testing (QST) in the diagnosis of trigeminal neuropathy and neuropathic pain. Fifty-eight patients (14 men), 34 with sensory deficit within the inferior alveolar nerve (IAN) and 24 within the lingual nerve (LN) distribution, were included. Twenty-six patients (45%) reported neuropathic pain. Patients underwent blink reflex (BR) test and thermal QST; sensory neurography was done to the IAN patients. Results of clinical sensory testing were available from the charts of 48 patients revealing abnormal findings in 77% of the IAN and in 94% of the LN patients. The BR test was abnormal in 41%, neurography in 96%, and QST in 91% of the IAN patients. In the LN group, BR was abnormal in 33%, and QST in 100% of the patients tested. Neurophysiologic tests and QST verified the subjective sensory alteration in all but 2 IAN patients, both with old injuries, and 4 LN patients who did not undergo QST. When abnormal, thermal QST showed elevation of warm and cold detection thresholds (hypo/anesthesia), hypoalgesia was less marked, and heat allodynia was only occasionally present. Contralateral thermal hypoesthesia after unilateral injury was found in 14 patients. It was associated with the occurrence of neuropathic pain (P=0.016). Axonal Abeta afferent damage was less severe in the IAN patients with pain than in those without pain (P=0.012). Neurophysiologic tests and thermal QST provide sensitive tools for accurate diagnosis of trigeminal neuropathy and study of pathophysiological features characteristic to human neuropathic pain.     

格林-巴利综合征腰丛神经磁共振成像研究

目的探讨磁共振神经成像(MRN)对格林-巴利综合征(GBS)的诊断和鉴别诊断价值。方法对临床诊断为GBS(21例)、慢性炎症性脱髓鞘性多发性神经病(CIDP,4例)患者及正常人(30例)行腰丛神经MRN检查。正常组观测腰2~5神经根、神经节及神经干、股神经的形态、大小及信号;GBS及CIDP组观察神经及其周围的改变,测量右侧腰4神经根、神经节、神经干及股神经的短轴径线及神经肌肉信号比。结果正常组MRN可清晰显示腰2~5神经的走行,神经节呈圆或椭圆形膨大,大小约为3~6mm,神经根及干呈条状,边缘光滑,大小约为2~5mm,神经节信号高于神经根和干,40%的神经根鞘有少量脑脊液,股神经、闭孔神经、腰骶干的显示率分别为100%、83.3%、43.3%。80.9%的GBS腰丛神经周围有片状模糊高信号,神经根和节大小和信号无明显改变,25%神经干增粗,50%的神经干信号增高,边缘模糊。CIDP神经周围无片状高信号,神经根及节无明显增大,神经干及股神经均明显增粗,信号增高。结论MRN可清晰显示腰丛神经及主要大分支;GBS在神经周围有渗出病变,神经增粗不明显,CIDP神经周围无渗出病变,神经干明显增粗。MRN可作为GBS及CIDP诊断和鉴别诊断的重要手段。     

Cluster headache attacks and multiple sclerosis

We report the case of a patient who developed typical cluster headache attacks and was diagnosed as having multiple sclerosis (MS) at the same time. The headache attacks resolved after i.v. treatment with methylprednisolone. MR imaging showed a pontine demyelinating lesion involving the trigeminal nerve root inlet area, on the same side as the pain. The association between cluster headache and MS has been rarely described before. This case suggests that in patients with cluster headache neuroimaging is often useful in order to exclude structural lesions.     

磁共振序列在颅神经血管成像中的应用价值

目的通过3D-SPACE序列、3D-CISS序列、3D-VIBE序列及3D-TOF序列对神经、血管及其空间关系的显示能力,从中选择优异的序列组合来展现神经与血管的关系。材料与方法对三叉神经痛、面肌痉挛或舌咽神经痛的患者进行MR常规及上述4种血管神经成像技术进行扫描,查看它们在MPR或MIP重建中神经、血管的成像特点。结果与3D-CISS序列相比,3D-SPACE序列能更加敏感地显示责任血管,更好地体现神经与血管的关系;与3D-VIBE序列相比,3D-TOF序列能更清晰地显示整体的血管走形。结论 3D-SPACE序列能更好的显示神经走向及判断神经与血管的关系,3D-TOF序列能在MIP重建中显示整体的血管并判断血管来源,两者结合能更好地展现MR在血管神经成像的优势。     

Comparison of clinical symptoms and magnetic resonance angiographic (MRA) results in patients with trigeminal neuralgia and persistent idiopathic facial pain. Medium-term outcome after microvascular decompression of cases with positive MRA findings

Neurovascular compression (NC) seems to have been confirmed as the major cause of classical trigeminal neuralgia (TN). In spite of the large number of surgically positive cases, however, there are still cases where no vascular compression of the trigeminal nerve can be found. To evaluate whether NC could be demonstrated preoperatively, high-resolution magnetic resonance angiography (MRA) was performed in 287 consecutive patients with TN and persistent idiopathic facial pain (PIFP) on a 0.5-T and a 1-T MR unit. Depending on the clinical symptoms, the TN cases were divided into typical TN and trigeminal neuralgia with non-neuralgic interparoxysmal pain (TNWIP) groups. Microvascular decompression (MVD) was performed in 103 of the MRA-positive cases. The patients were followed up postoperatively for from 1 to 10 years. The clinical symptoms were compared with the imaging results. The value of MRA was assessed on the basis of the clinical symptoms and surgical findings. The outcome of MVD was graded as excellent, good or poor. The clinical symptoms were compared with the type of vascular compression and the outcome of MVD. The MRA image was positive in 161 (56%) of the 287 cases. There were significant differences between the clinical groups: 66.5% of the typical TN group, 47.5% of the TNWIP group and 3.4% of the PIFP group were positive. The quality of the MR unit significantly determined the ratio of positive/negative MRA results. The surgical findings corresponded with the MRA images. Six patients from the MRA-negative group were operated on for selective rhizotomy and no NC was found. Venous compression of the trigeminal nerve was observed in a significantly higher proportion in the background of TNWIP than in that of typical TN on MRA imaging (24.1% and 0.8%, respectively) and also during MVD (31.2% and 1.2%, respectively). Four years following the MVD, 69% of the patients gave an excellent, 23% a good and 8% a poor result. The rate of some kind of recurrence of pain was 20% in the typical TN and 44% in TNWIP group. The rate of recurrence was 57% when pure venous compression was present. The only patient who was operated on from the PIFP group did not react to the MVD. The clinical symptoms and preoperative MRA performed by at least a 1-T MR unit furnish considerable information, which can play a role in the planning of the treatment of TN.     

3D-CISS序列对颅内表皮样囊肿的诊断价值

目的评价MR 3D稳态构成干扰序列(CISS)对颅内表皮样囊肿的诊断价值.方法回顾性分析12例手术病理证实的颅内表皮样囊肿(EC)的3D-CISS影像表现,并与常规MR T1WI、T2WI进行对照.结果常规MRI发现病灶11例,8例信号强度与脑脊液相似,难与蛛网膜囊肿鉴别,11例均不能辩认肿瘤的确切边界.3D-CISS发现病灶12例,均表现为高信号脑脊液中的低信号充盈缺损,信号不均,10例呈沿脑池脑室匐行生长,3例包绕三叉神经,1例推挤三叉神经使之移位,1例部分包绕基底动脉.结论较之常规MR,3D-CISS在发现病灶、显示肿瘤的生长方式及复杂的信号特点方面更敏感,对表皮样囊肿的诊断与鉴别诊断更可靠,并能清楚显示肿瘤与周围重要结构的关系,为临床提供更丰富的信息,是表皮样囊肿的最佳检查序列.