目的　探讨小脑下前动脉血管袢及颈静脉球的形态特点与突发性聋的关系。  方法　选取单侧起病突发性聋患者80例（80耳），36例健康成人（72耳），分别设为突聋组（80耳）和对照组（72耳），回顾分析其内耳MRI扫描及三维重建图像，观察以下指标：（1）小脑下前动脉血管袢是否突入内听道；（2）小脑下前动脉血管袢与面神经及前庭蜗神经的位置关系；（3）颈静脉球与周围结构的位置关系。  结果  （1）小脑下前动脉血管袢突入内听道：突聋组35耳（43.8%）、对照组29耳（40.3%），P=0.665，差异无统计学意义。（2）小脑下前动脉血管袢与面神经及前庭蜗神经的位置关系分型：突聋组上位型9耳（11.3%）、中间型53耳（66.3%）、下位型11耳（13.8%）、前位型7耳（8.8%）、后位型0耳，对照组上位型8耳（11.1%）、中间型46耳（63.9%）、下位型11耳（15.3%）、前位型7耳（9.7%）、后位型0耳。P=0.771，差异无统计学意义。（3）颈静脉球位置分型：突聋组I型2耳（2.5%）、Ⅱ型40耳（50.0%）、Ⅲ型36耳（45.0%）、Ⅳ型2耳（2.5%），对照组I型0耳、Ⅱ型19耳（26.4%）、Ⅲ型46耳（63.9%）、Ⅳ型7耳（9.7%)。P<0.001，差异有统计学意义。  结论　突发性聋与颈静脉球的位置相关，与小脑下前动脉血管袢是否突入内听道无关，与面神经及前庭蜗神经的位置无关。颈静脉球Ⅱ型（后上型）较其它类型人群患突发性聋的比例更高。

Objective　To investigate the association between sudden deafness (SD) and morphological character of anterior inferior cerebellar artery loop and jugular bulb.　Methods　MRI scanning and three-dimensional reconstruction of inner ear was observed in 80 patients with sudden deafness of unilateral outset (80 ears) and 36 healthy adults (72 ears). The SD group consisted of patients with SD of unilateral outset (80 ears) and the control group consisted of healthy adults (72 ears). The primary endpoints: (1) whether anterior inferior cerebellar artery loop juts out into the internal auditory canal (IAC), (2) the spatial relationship between the anterior inferior cerebellar artery loop, the facial nerve and the cochleovestibular nerve, (3) the spatial relationship between the jugular bulb and surrounding structures.  Results　(1) Proportion of anterior inferior cerebellar artery loop jutting out into IAC did not differ in both groups: 35 ears (43.8%) in the SD group and 29 ears (40.3%) in the control group, P=0.665. (2) Neither did the proportion of different types that were classified by spatial relationship between the anterior inferior cerebellar artery loop, the facial nerve and the cochleovestibular nerve. 9 superior type (11.3%), 53 medial type (66.3%) , 11 inferior type (13.8%), 7 anterior type (8.8%)  and no posterior type could be observed in the SD group.  8 superior type (11.1%) , 46  medial type (63.9%), 11  inferior type (15.3%), 7 anterior type (9.7%) and no posterior type could be observed in the control group, P=0.771. (3) The proportion of jugular bulb types differed significantly between two groups. 2 were type I (2.5%) , 40 medial type Ⅱ(50.0%), 36type Ⅲ (45.0%) , 2 type Ⅳ(2.5%) in SD group. There were no type I, 19 type Ⅱ(26.4%) , 46 type Ⅲ (63.9%), 7 type Ⅳ (9.7%)  in the control group( P＜0.001).     Conclusion    Different jugular bulb subtypes are associated with higher risk of SD. Jugular bulb type Ⅱ is associated with high risk of SD among type I, Ⅲ and Ⅳ. Whether the anterior inferior cerebellar artery loop juts out into IAC and the relationship among the anterior inferior cerebellar artery loop, the facial nerve and the cochleovestibular nerve are not associated with higher risk of SD.