目的　为面神经脑池段与其周围血管是否存在压迫或接触提供形态学诊断依据。  方法　选取采用MRI 3D-FIESTA和3D-TOF序列扫描的检查正常者140例和单侧面肌痉挛患者70例，在MPR重建影像上观测I-CSFN-SV的血管直径、与脑干距离和血管自身角度、夹角及其与面肌痉挛发病率之间的关系。   结果　正常组、面肌痉挛健侧组和面肌痉挛患侧组I-CSFN-SV的血管直径、与脑干距离、血管自身角度、夹角分别为（0.48±0.03）mm、（0.49±0.04）mm、（0.71±0.06）mm和（8.69±0.62）mm、（8.66±0.75）mm、（5.93±0.47）mm，（74.39±2.33）°、（72.66±2.54）°、（48.57±3.28）°和（85.60±3.07）°、（86.75±2.73）°、（88.41±3.76）°，面肌痉挛患侧组与正常组、面肌痉挛健侧组I-CSFN-SV的血管直径、与脑干距离、血管自身角度均有显著性差异（P＜0.05），夹角无显著性差异（P＞0.05），且随着I-CSFN-SV与脑干距离的增加则发病率呈下降趋势，血管直径的增加和血管自身角度的减小则发病率呈上升趋势，夹角变化与发病率之间无显著性变化趋势。  结论　I-CSFN-SV的血管直径、与脑干距离和血管自身角度是诊断是否存在压迫或接触的重要诊断指标，血管自身角度越小、血管直径越粗和相交处与脑干距离越近，则越容易出现面肌痉挛病变。

Objective　To provide evidence for the morphological diagnosis on the oppression and contact of the cisternal segment of facial nerve with its surrounding vessels.　Methods　140 normal and 70 patients with unilateral hemifacial spasm were selected by MRI 3D-FIESTA and 3D-TOF sequence scanning. The following parameters were observed in the MPR reconstruction image, including the vascular diameter, distance to brainstem vascular self angle and included angle at the intersection of the cisternal segment of facial nerve with its surrounding vessels, and its relationship with the morbidity of hemifacial spasm.　Results　The vascular diameter, distance to brainstem, vascular self angle and included angle at the intersection of the cisternal segment of facial nerve with its surrounding vessels were (0.48±0.03)mm, (0.49±0.04)mm, (0.71±0.06) mm and (8.69±0.62) mm, (8.66±0.75)mm, (5.93±0.47) mm and (74.39±2.33) °, (72.66±2.54) °, (48.57±3.28) ° and (85.60±3.07) °, (86.75±2.73) °, (88.41±3.76) ° on the normal group, uninjured group of hemifacial spasm, ipsilateral group of hemifacial spasm， respectively. There were significant difference between the ipsilateral group of hemifacial spasm to the normal group, uninjured group of hemifacial spasm at the vascular diameter, to brainstem distance and vascular self angle at the intersection of the cisternal segment of facial nerve with its surrounding vessels (P<0.05), there was no significant difference at the included angle(P>0.05). The morbidity decreased with the increase of intersection to brainstem distance, increased with the enlargement of vascular diameter and the reduction of vascular self angle. There was no significant change between the included angle to morbidity.　Conclusions　The vascular diameter, distance to brainstem and vascular self angle at the intersection of the cisternal segment of facial nerve with its surrounding vessels are important diagnostic markers whether the oppression or contact exists. The lesser of the vascular self angle, the larger of the vascular diameter and the shorter of the distance between the intersection and brainstem, the more prone the patient is to hemifacial spasm lesions.