Magnetic resonance imaging of idiopathic trigeminal neuralgia

Seventeen patients with idiopathic trigeminal neuralgia (ITN) and seven subjects of control group were evaluated with magnetic resonance imaging (MRI). Vascular contact at the proximal portion of the preganglionic segment (PGS) of the trigeminal nerve was observed in 100% of ITN on the affected side, 76% of ITN on the non-affected side, and 21% of control group. Deformity of the PGS was observed in 65% of ITN on the affected side, and in none of ITN on the non-affected side or control group. Non-surgical treatments were effective in all of the 6 patients without deformed PGS, but they failed to control trigeminal neuralgia in 4 of 11 patients with deformed PGS. This preliminary study suggests that MRI could be used for the clinical assessment of trigeminal neuralgia before treatment.     

磁共振3D-FIESTA在原发性三叉神经痛诊断中的应用

目的 研究MR三维稳态进动快速成像(3D-FIESTA)序列对原发性三叉神经痛的诊断价值.方法 对23例三叉神经痛患者行3D-FIESTA序列成像并多平面重建,分析患侧组与健侧组三叉神经与邻近血管关系.结果 患侧组与健侧组神经血管接触阳性比例分别为20/23与11/23,神经受压推移比例分别为6/23与0/23,经统计学分析,2组间的差异均有统计学意义(P<0.05).结论 MR 3D-FIESTA序列可以清晰显示三叉神经与邻近血管的关系,对原发性三叉神经痛的诊断具有重要价值.     

磁共振断层血管成像对原发性三叉神经痛的诊断价值

目的：探讨磁共振断层血管成像(MRTA)对原发性三叉神经痛(ITN)患者神经血管关系的诊断价值及可靠性。方法回顾性分析280例 ITN 患者的临床及 MR 资料,并与手术结果进行盲法对照。结果280例 ITN 患侧神经血管接触、可疑接触或压迫共267例(阳性率95.3%),健侧有66例(假阳性率23.6%);120例手术者,术中发现神经血管接触或压迫118例。患侧与健侧神经血管接触或压迫比较差异有统计学意义(P <0.05)。以手术结果为金标准,MRTA 诊断神经血管接触或压迫的特异度、灵敏度、诊断符合率分别为100%,96.6%,96.7%。结论MRTA 能可靠地显示 ITN 神经血管的关系,其诊断灵敏度和准确率高,对ITN 病因诊断和手术治疗提供客观的依据。     

高危原发性三叉神经痛的介入治疗

目的 评价经皮穿刺微球囊压迫三叉神经节(PMC)治疗高危原发性三叉神经痛方法的临床效果.方法 回顾性分析从2001年1月至2007年12月采用Mullan方法治疗3053例原发性三叉神经痛患者中804例高危患者采用PMC技术治疗的临床资料.结果 对804例患者行833次手术.术后即刻成功率为97.3%.平均随访36个月,疼痛复发率为6.8%.感觉异常的发生率为3.8%,无角膜溃疡,咀嚼肌无力约占2/3,复视占0.2%.结论 PMC方法是高危原发性三叉神经痛的首选且十分有效的治疗方法之一,尤其对于疼痛累及第一支且高危的患者更有优势.     

CT引导下半月神经节射频热凝术

目的 探讨CT引导下半月神经节射频热凝技术中的应用,并观察该技术治疗三叉神经痛病人的临床效果.方法 原发性三叉神经痛病人35例,先行CT斜冠状位扫描,定位定向确定穿刺进针点及方向,然后通过轴位扫描及三维重建精确穿刺针位置及其与卵圆孔关系,连接射频仪调试并进行热凝治疗.结果 所有病人半月神经节穿刺均顺利安全完成,穿刺时间为48~350 s(平均78.6 s±34.6 s),术后疼痛完全消失者29例,疼痛视觉模拟评分(VAS)<3者4例,2例病人VAS>4,所有病人均未出现严重的并发症.结论 CT引导下半月神经节射频热凝术定位定向准确,穿刺时间短,安全性高,临床治疗效果确切.     

Transoval trigeminal cisternography and glycerol injection in trigeminal neuralgia

In a series of 25 consecutive patients suffering from essential trigeminal neuralgia, transoval glycerol injection following H?kanson was performed in order to alleviate the pain attacks. This treatment proved to be successful in 76% of the patients. No major side-effects were reported. Authors stress the importance of a precise cisternography of Meckel's cave to ascertain the correct position of the needle, before injecting the glycerol. They discuss their mode of conducting the examination in using a conventional radiologic set-up. Transoval glycerol injection is a valuable interventional radiologic procedure and has to be taken into account as an alternative treatment of essential trigeminal neuralgia, especially when current therapeutic measures have failed.     

Thalamic metabolic alterations with cognitive dysfunction in idiopathic trigeminal neuralgia: a multivoxel spectroscopy study

Introduction

Although abnormalities in metabolite compositions in the thalamus are well described in patients with idiopathic trigeminal neuralgia (ITN), differences in distinct thalamic subregions have not been measured with proton magnetic resonance spectroscopy (¹H-MRS), and whether there are correlations between thalamic metabolites and cognitive function still remain unknown.

Methods

Multivoxel MRS was recorded to investigate the metabolic alterations in the thalamic subregions of patients with ITN. The regions of interest were localized in the anterior thalamus (A-Th), intralaminar portion of the thalamus (IL-Th), posterior lateral thalamus (PL-Th), posterior medial thalamus (PM-Th), and medial and lateral pulvinar of the thalamus (PuM-Th and PuL-Th). The N-acetylaspartate to creatine (NAA/Cr) and choline to creatine (Cho/Cr) ratios were measured in the ITN and control groups. Scores of the visual analogue scale (VAS) and the Montreal Cognitive Assessment (MoCA) were analyzed to correlate with the neuroradiological findings.

Results

The NAA/Cr ratio in the affected side of PM-Th and PL-Th in ITN patients was statistically lower than that in the corresponding regions of the thalamus in controls. The NAA/Cr ratio in the affected PM-Th was negatively associated with VAS and disease duration. Furthermore, decreases of NAA/Cr and Cho/Cr were detected in the affected side of IL-Th, and lower Cho/Cr was positively correlated with MoCA values in the ITN group.

Conclusions

Our result of low level of NAA/Cr in the affected PM-Th probably serves as a marker of the pain-rating index, and decreased Cho/Cr in IL-Th may be an indicator of cognitive disorder in patients with ITN.     

Magnetic resonance in trigeminal neuralgia]

One of the possible causes of the so-called "essential" trigeminal neuralgia is a neurovascular compression of the fifth cranial nerve root at the pons. The demonstration of this hypothesis could orientate the surgical treatment to microvascular decompression. In order to evaluate the role of MRI in the diagnosis of trigeminal neuralgia due to neurovascular compression, the authors present the results of a prospective evaluation of the cranial MR studies of 18 neuralgic patients in comparison with a retrospective evaluation of the cranial MR studies of 50 healthy control subjects. The results show that neurovascular compression can be demonstrated in 83.3% of the neurological patients. In all cases a good correlation between the clinical symptoms, the side of positive MR findings and the surgical findings, when available, was demonstrated. On the other hand, neurovascular compression was demonstrated in 28% of the healthy control subjects. The authors conclude that neurovascular compression can be demonstrated in a high percentage of patients with the so-called "essential" trigeminal neuralgia. Compared with the other imaging modalities (angiography, Computed Tomography) MRI is the best technique in the diagnosis of this disease. In fact, MRI is not only able to differentiate the symptomatic from the essential type of neuralgia, but is also very sensitive in the identification of trigeminal neuralgia due to neurovascular compression. This diagnosis could direct the surgical treatment to microvascular decompression.     

Gamma-knife radiosurgery for trigeminal neuralgia

Gamma knife was installed at the PD Hinduja National Hospital and Medical Research Centre, Mumbai, India, in January 1997. In the first year of gamma-knife radiosurgery to January 1998, we treated 110 patients, of whom six had medically refractory trigeminal neuralgia. Seven treatments were administered to this group of six patients (one had bilateral neuralgia). This report evaluates the effectiveness of radiosurgery treatment in these patients. The median age of the patients was 56 years and there were five males and one female. Following Leksell stereotactic frame fixation, a magnetic resonance imaging scan was done in all. The Leksell gamma plan was used for planning. A radiosurgery dose of 70-80 Gy was delivered to the trigeminal root entry zone, 2-4 mm anterior to the junction of the pons and trigeminal nerve with a single 4 mm collimator helmet. Complete pain relief was achieved in four patients. Two had partial relief. No patient developed any radiosurgery related morbidity during the follow-up period of 5-16 months. Radiosurgery seems to be an effective approach for medically or surgically refractory trigeminal neuralgia.     

Angiographic demonstration of a trigeminal neurinoma

The case of a young man with a trigeminal neurinoma arising from the cerebellopontine angle and extending to the Gasserion ganglion is presented and the angiographic findings are described.     

桥小脑角区显微手术治疗三叉神经痛101例

目的　介绍１０１ 例三叉神经痛经桥小脑角显微手术治疗经验。方法　分析１０１ 例三叉神经痛的病因、术式选择及复发率，并就减少并发症进行探讨。结果　３ 例胆质瘤切除术后三叉神经痛症状均消失。余９８ 例术后疼痛即刻消失者８８ 例；１０ 例仍疼痛但程度减轻，均存在于６２ 例行微血管减压术式者中，其中５ 例于术后１０ ｄ 内疼痛消失，另５ 例口服药物可控制。近期有效率１００ ％ ，近期治愈率８９８ ％ 。无死亡病例。共随访成功６５ 例，随访时间０５ ～７ ａ ，复发６例。结论　治疗三叉神经痛的桥小脑角区显微是最接近其病因的治疗，并视术中情况进一步实施微血管减压术或感觉根部分切断术，是治疗三叉神经痛较理想的手术。     

血管压迫性三叉神经痛的MRI研究

目的 采用MR断层血管成像术对血管压迫性三叉神经痛的责任血管作深入研究。方法 235侧正常三叉神经及147侧有三叉神经痛症状的三叉神经MR三维时间飞跃（3D-TOF）扫描图像由2名医师以盲法读片，评判所见三叉神经周围有无血管及其与血管的关系，并记录所见血管的直径、血管至脑干的距离及血管的走行方向。分别进行团体t检验和卡方检验以明确有无统计学意义。结果 共有242侧三叉神经周围可以见到关系密切的血管，其中111侧为无症状组，131侧为有症状组，经统计表明有症状组三又神经所见责任血管距脑干的距离中位数为2mm，明显较无症状组（中位数为4mm）短（P〈0．01），有症状组三叉神经所见责任血管与血管夹角（89．3％，117／131）〉45。（P〈0．01）。无症状组中仅有1例（0．4％，1／235）发现三叉神经受血管推压移位，而在有症状组中有45例（30．6％，45／147），因此有症状组三叉神经受压推移率明显高于无症状组（P〈0．01）。结论 MRI对血管压迫性三叉神经痛的责任血管的评估非常有价值。责任血管距脑干的最短距离及走行与血管压迫性三叉神经痛的发病非常有关。     

Persistent trigeminal artery associated with trigeminal neuralgia: hypothesis of neurovascular compression

Introduction The aim of this study was to determine the prevalence of persistent trigeminal artery (PTA) associated with trigeminal neuralgia (TN). Methods From January 1998 to January 2004, 288 MRI scans of patients examined for trigeminal deficits were retrospectively evaluated. MRI was performed at 1.5 T. Scan protocols included cerebral TSE T2-weighted imaging, contrast enhanced SE T1-weighted imaging and thin-section 3D T2-weighted imaging of the temporal bones, 3D TOF pre- and postcontrast MR angiography. TN was defined as episodes of intense stabbing, electric shock-like pain in areas of the face supplied by the trigeminal branches. Neurovascular compression (NVC) was assumed to be present if the patient showed clinical features of TN, if there was contact between an artery and the trigeminal nerve on the affected side, and if other pathology had been excluded. The prevalence and confidence intervals were calculated (95% CI of the prevalence was based on the exact binomial distribution). Results Of 288 patients, 136 matched the criteria for TN. In this series a PTA was detected in three patients, which in all patients was on the same side as the TN. The prevalence of a PTA in patients presenting with TN was 2.2% (CI 0.005–0.06). Conclusion Previous studies have shown PTA as an incidental finding in 0.1–0.6% of cerebral angiograms. The prevalence of a PTA in patients with TN was 2.2%. With respect to the clinical significance, a PTA has to be considered in TN and the diagnosis of a PTA can easily be made using MR imaging/angiography.     

低场强磁共振CBASS序列在三叉神经痛病因诊断中的应用价值

目的:探讨低场强MRI CBASS序列在三叉神经痛(TN)病因中的研究价值。方法:对50例TN患者依次采用CBASS序列,结合FE序列,FE3D-TOF序列进行检查,对CBASS序列成像MRI表现及手术结果作回顾性分析。结果:①50例TN患者中,肿瘤性病变7例,其它3例,排除上述继发性TN10例;40例原发性TN患者入选,疼痛侧MRICBASS序列发现有三叉神经血管压迫或接触29例(29/40),非疼痛侧有三叉神经血管接触9例(9/40),两组相比有显著性差异2=20.050,(P<0.0001);②50例患者均行手术治疗,CBASS序列对原发性TN诊断的敏感性为93.1%,特异性为81.8%,准确性90.01%,假阴性为18.21%,假阳性为6.9%。结论:三叉神经脑池段血管压迫或接触是TN的首要原因,CBASS序列成像能清晰显示三叉神经与邻近血管、肿瘤病变或其他病变之间的关系,对临床诊治具有重要指导意义。     

三维快速平衡稳态进动MRI对三叉神经痛的诊断研究

目的探讨磁共振三维快速平衡稳态进动（3D-FIESTA）序列对三叉神经痛（trigeminal neuralgia,TN）患者神经血管关系的诊断价值及可靠性。方法对25例正常对照及25例TN患者三叉神经行3D-FIESTA序列成像并多平面重建,记录该序列对神经血管关系的诊断结果,其中15例与手术结果对照。结果正常对照组双侧及TN组患侧神经血管接触或压迫的阳性率分别为24%与87.5%,二者有非常显著性差异（P〈0.001）。3D-FIESTA对15例TN患者诊断的敏感度、准确率分别为93%与67%。结论 3D-FIESTA序列是诊断神经血管关系较为敏感可靠的序列,可作为TN患者的首选序列。     

血管压迫性三叉神经痛责任血管的3.0T MRI研究

目的 采用3.0 T MRI显示三叉神经及周围血管的解剖关系,分析产生原发性三叉神经痛(TN)的血管压迫特点.方法 选择50例TN患者(50支TN患侧和50支TN对侧三叉神经;其中23例行微血管解压术)和50名没有面部疼痛的志愿者(100支非TN三叉神经),在3.0TMR采用三维快速稳态梯度回波序列(3D TRU-FISP)及3D 三维时间飞跃(TOF-MRA)扫描.若判断TN患者为静脉病变,并行增强3D快速小角度反转序列(3DFLASH)扫描.以上图像融合重建成虚拟脑池图,评价神经血管压迫程度分级(1级无压迫,2级静脉性压迫,3级神经与动脉接触,4级有动脉压痕,5级动脉压迫导致神经明显移位),以及血管接触神经的方位(三叉神经的上侧或其他侧)、血管神经接触点的位置(近:位于三叉神经脑池段近脑干1/3长度区域,远:位于三叉神经脑池段远脑干2/3长度区域).3D TRU-FISP序列重建的冠、矢状面图像用于测量神经长度、神经横截面及脑池面积.采用卡方检验观察2组的三叉神经:血管压迫神经引起神经切迹或移位(4级和5级)、血管神经压迫点和神经出脑干处距离、血管压迫神经的位置位于神经上侧方的发生率.采用t检验观察测量数值的统计学意义,并用Logisac回归分析三叉神经痛的发病因素.结果 两序列及融合图像可以清晰显示神经血管的关系,与23例微血管解压术中所见吻合度高,术后症状消失或明显减轻21例.血管压迫或接触三叉神经的发生率在志愿者组(1级79支,2级5支,3级8支,4级8支)、TN对侧(1级27支,2级6支,3级9支,4级8支)及TN患侧(1级4支,2级t2支,3级12支,4级7支,5级15支)分别为21.0％(21/100)、46.0％ (23/50)、92.0％ (46/50).TN患侧三叉神经较志愿者三叉神经血管受压迫程度4、5级者差异有统计学意义(x2=27.0,P ＜0.01);血管接触点的位置在TN患侧近32支、远14支,在志愿者近4支、远17支(x2=14.8,p＜0.01);压迫血管位置中,TN患侧位于神经上侧36支、其他侧10支,志愿者中位于神经上侧5支、其他侧16支(x2=18.0,P＜0.01);所在层面脑桥池面积,TN患侧为(183.9+52.5) mm2、对侧为(217.8±58.8)mm2(t=-3.04,P＜0.01);脑池段神经中点截面积,TN患侧为(6.3±1.3)mm2、对侧为(7.7±1.6) mm2(t=-4.8,P＜0.01);脑池段神经长度,TN患侧为(8.0±1.9)mm、对侧为(9.0±2.0)mm(t=-2.64,P＜0.05),差异均有统计学意义.结论 MR可以清楚显示TN患者血管与三叉神经的关系,受压迫神经位置更靠神经近端及头侧、神经所在层面脑桥池面积较小者,均是较强的手术指征.     

面肌抽搐与三叉神经痛的MRI诊断

目的　探讨面肌抽搐及三叉神经痛患者血管压迫病因的MR表现及其诊断价值。方法　回顾性分析了 12 0例面肌抽搐及三叉神经痛患者MR表现及手术结果。结果　 (1) 6 3例面肌抽搐患者MR显示 12 6侧面听神经共发现 5 8侧存在神经血管压迫或接触 ,17侧可疑接触 ;5 7例三叉神经痛患者MR显示 114侧三叉神经共发现 4 5侧存在神经血管压迫或接触 ,12侧可疑接触。 (2 )统计学分析结果 :面肌抽搐患者症状侧和无症状侧差异有非常显著性意义 (χ2 =31 6 6 ,P <0 0 0 1) ;三叉神经痛患者症状侧和无症状侧差异有非常显著性意义 (χ2 =4 2 98,P <0 0 0 1)。 (3)根据手术结果 ,MR诊断面肌抽搐及三叉神经痛患者神经血管压迫或接触的敏感度为 94 % ,准确度为 83% ,阳性似然比为1 88。结论　MRI能清晰显示三叉神经脑池段与毗邻血管之间的关系 ,对面听神经及三叉神经血管压迫或接触的正确诊断具有较高的敏感度和准确度 ,为临床医师提供术前评估和指导治疗有极其重要的意义。