Miller Jonathan P, Acar Feridun, Hamilton Bronwyn E, Burchiel Kim J
Departments of Neurological Surgery, Oregon Health & Science University, Portland, Oregon, USA.
J Neurosurg. 2009 Apr;110(4):627-32. doi: 10.3171/2008.6.17620.
Neurovascular compression (NVC) of the trigeminal nerve is associated with trigeminal neuralgia (TN), but also occurs in many patients without facial pain. This study is designed to identify anatomical characteristics of NVC associated with TN.
Thirty patients with Type 1 TN (intermittent shocklike pain) and 15 patients without facial pain underwent imaging for analysis of 30 trigeminal nerves ipsilateral to TN symptoms, 30 contralateral to TN symptoms, and 30 in asymptomatic patients. Patients underwent 3-T MR imaging including balanced fast-field echo and MR angiography. Images were fused and reconstructed into virtual cisternoscopy images that were evaluated to determine the presence and degree of NVC. Reconstructed coronal images were used to measure nerve diameter and crosssectional area.
The incidence of arterial NVC in asymptomatic nerves, nerves contralateral to TN symptoms, and nerves ipsilateral to TN symptoms was 17%, 43%, and 57%, respectively. The difference between symptomatic and asymptomatic nerves was significant regarding the presence of NVC, nerve distortion, and the site of compression (p < 0.001, Fisher exact test). The most significant predictors of TN were compression of the proximal nerve (odds ratio 10.4) and nerve indentation or displacement (odds ratio 4.3). There was a tendency for the development of increasingly severe nerve compression with more advanced patient age across all groups. Decreased nerve size was observed in patients with TN but did not correlate with the presence or extent of NVC.
Trigeminal NVC occurs in asymptomatic patients but is more severe and more proximal in patients with TN. This information may help identify patients who are likely to benefit from microvascular decompression.
三叉神经的神经血管压迫（NVC）与三叉神经痛（TN）相关，但也见于许多无面部疼痛的患者。本研究旨在确定与TN相关的NVC的解剖学特征。
30例1型TN（间歇性电击样疼痛）患者和15例无面部疼痛的患者接受成像检查，以分析30条与TN症状同侧的三叉神经、30条与TN症状对侧的三叉神经以及30条无症状患者的三叉神经。患者接受了3-T磁共振成像检查，包括平衡快速场回波成像和磁共振血管造影。图像融合并重建为虚拟脑池造影图像，用于评估NVC的存在和程度。重建的冠状图像用于测量神经直径和横截面积。
无症状神经、TN症状对侧神经和TN症状同侧神经的动脉NVC发生率分别为17%、43%和57%。在NVC的存在、神经扭曲和压迫部位方面，有症状神经和无症状神经之间的差异具有统计学意义（p < 0.001，Fisher精确检验）。TN的最显著预测因素是近端神经受压（优势比10.4）和神经压迹或移位（优势比4.3）。在所有组中，随着患者年龄的增加，神经压迫有加重的趋势。TN患者观察到神经尺寸减小，但与NVC的存在或程度无关。
三叉神经NVC在无症状患者中也会出现，但在TN患者中更严重且更靠近近端。这些信息可能有助于识别可能从微血管减压中获益的患者。
