摘要目的:探讨小脑下前动脉前(AICA)血管袢的位置对面听神经血管压迫综合征患者典型面、听神经症状的影响。方法:回顾性研究。纳入兰州大学第二医院核磁共振科311例患者(622侧耳)内耳MR可变翻转角三维快速自旋回波(3D-SPACE)序列影像资料，其中男113例、女198例，年龄22～77(48±10.8)岁。统计AICA血管袢发生率及其Chavda分型占比。311例中，单侧面肌痉挛患者107例，比较其患侧(107侧)与健侧(107侧)AICA血管袢发生率、Chavda分型占比，以及AICA走行全程与神经有无接触。自血管袢阳性患者中选择90例(148侧)为血管袢组，比较不同Chavda分型AICA血管袢患者临床表现的差异；将ChavdaⅡ型及Ⅲ型的63侧耳纳入内耳道内血管袢组，将内耳道中的神经分布分为4个象限，观察AICA血管袢与面、听神经接触的位置象限不同的患者间典型面、听神经症状的差异。结果:本组311例622侧患者AICA血管袢的发生率为65.43%(407/622)，其中双侧AICA血管袢形成144例、单侧119例，ChavdaⅠ型170侧(41.77%)、Ⅱ型189侧(46.44%)、Ⅲ型48侧(11.79%)。107例单侧面肌痉挛患者健侧AICA血管袢发生率为71.96%(77/107)、患侧70.09%(75/107)，两侧比较差异无统计学意义( P>0.05)；健侧和患侧神经血管接触率分别为57.9%(62/107)、43.9%(47/107)，差异有统计学意义(χ 2＝4.207, P<0.05)。血管袢组90例(148侧)中，不同Chavda分型患者面肌痉挛、听力下降、耳鸣症状的发生率比较，差异均无统计学意义( P值均>0.05)；内耳道内血管袢组共63侧，内耳道内AICA血管袢所处象限不同患者的典型面、听神经症状比较，差异均无统计学意义( P值均>0.05)。 结论:内耳MR 3D-T 2-SPACE成像可清晰显示AICA血管袢及其与内耳道的位置关系，血管袢深度、位置对面听神经压迫综合征典型面、听神经症状无明显影响。

abstractsObjective:To investigate whether the typical facial and acoustic nerve symptoms of in patients with facial and acoustic neurovascular compression syndrome are different in different positions of the anterior inferior cerebellar artery (AICA) vascular loop.Methods:Retrospective study. A total of 311 patients(622 side ears) who underwent magnetic resonance imaging(MRI) 3-dimensional sampling perfection with application optimized contrast using different flip angle evolutions(3D-SPACE) of the inner ear in the Lanzhou University Second Hospital were retrospectively analyzed. There were 113 males and 198 females, aged (48±10.8) years, with a range of 22-77 years. The incidence of AICA vascular loop and the proportion of Chavda classification were calculated. In 311 cases, 107 cases were unilateral hemifacial spasm. The incidence of AICA vascular loops, the proportion of Chavda classification and whether AICA had contact with nerve during the whole process were compared between the affected side (107 sides) and the normal side (107 sides). Then, 90 patients(148 ears) with positive vascular loop were selected as the vascular loop group, and the clinical manifestations of patients with AICA vascular loops of different Chavda types were compared. Sixty-three ears of Chavda types Ⅱ and Ⅲ were included in the inner auditory canal vascular loop group, and the nerve distribution in the internal auditory canal was divided into four quadrants. The differences of typical facial and acoustic nerve symptoms between patients with different quadrants of AICA vascular loop contacting facial and acoustic nerves were observed.Results:The incidence of AICA vascular loops was 65.43%(407/622) in 311 patients, including 144 cases of bilateral AICA loops, 119 cases of unilateral AICA loops, 170 sides of Chavda type Ⅰ (41.77%), 189 sides of type Ⅱ (46.44%), and 48 sides of type Ⅲ (11.79%). The incidence of AICA vascular loop was 71.96% (77/107) in the normal side and 70.09%(75 /107) in the affected side, and no significant difference was observed between the two sides ( P>0.05). The neurovascular contact rates of the normal side and the affected side were 57.9% (62/107) and 43.9%(47/107), respectively. the difference was statistically significant(χ 2=4.207, P<0.05). There was no significant difference in the incidence of hemifacial spasm, hearing loss and tinnitus among 90 patients (148 sides) in vascular loop group ( P>0.05); and there was no significant difference in the typical facial and acoustic nerve symptoms among patients with different quadrants of AICA vascular loop in the 63 sides inner auditory canal group ( P>0.05). No statistically significant differences were observed in the incidence of facial spasm, hearing loss, and tinnitus symptoms among 90 cases (148 sides) with different Chavda types in the vascular loop group (all P values >0.05). No statistically significant differences were observed in the typical facial acoustic nerve symptoms among 63 ears with different Chavda types in the quadrant of the inner auditory canal vascular loop group(all P values>0.05). Conclusions:MRI 3D-SPACE imaging of the inner ear can clearly show the vascular loop of AICA and its position relationship with the internal auditory canal. The depth and position of vascular loop have no difference with typical facial and auditory nerve symptoms of facial and auditory nerve compression syndrome.