3D-TOF磁共振血管成像诊断偏侧面肌痉挛的病因

目的　研究 3D TOF磁共振血管成像对偏侧面肌痉挛 (HFS)病因诊断的临床价值。方法　 3D TOF磁共振血管成像脑干薄层扫描 3 4例HFS患者和 3 5例对照 ,盲法诊断面神经根部解剖改变 ,两组对照分析。结果　 ( 1)HFS患者症状侧面神经根部受压迫 3 2侧 ( 94 % ) ,其中血管压迫 3 1侧( 91% ) ,肿瘤压迫 1侧 ( 3 % ) ;无症状侧受血管压迫 6侧 ( 18% ) ;对照组双侧受压迫 3侧 ( 4 % ) ,其中血管 2侧 ,肿瘤 1侧。 ( 2 )常见压迫血管分别为小脑前下动脉 11侧 ( 3 8% ) ,椎动脉单独或与小脑后下动脉联合 9侧 ( 2 9% ) ,小脑后下动脉 8侧 ( 2 5 % )。 ( 3 )面神经根部血管压迫发生HFS相对危险度的估计值为 3 7.2 8。 ( 4 )面肌痉挛侧面神经根部受血管压迫或包绕有 14侧 ( 4 5 % )。结论　研究提示 ,3D TOF磁共振血管成像为目前面肌痉挛病因诊断的最佳影像检查方法 ,HFS的主要病因为患侧面神经根部受血管压迫、包绕或与其紧密接触。

Contral study of 3D-TOF MRA in the etiologic diagnosis of hemifacial spasm

Objective To study the clinical significance of 3 dimensional time of flight magnetic resonance angiography (3D TOF MRA) for the pathogenesis of hemifacial spasm(HFS). Methods We investigated 34 patients with HFS and 35 controls without HFS by 3D TOF MRA by the enhancement of DTPA. Diagnosis of the presence of compressions in the root exit zone (REZ) of the facial nerves were made by two radiologist on an independent console. Results (1) In the patients studied, compressions of the REZ of the facial nerves were detected on 32 spastic sides (94%, neurovascular on 31 sides and tumor on 1 side), 6 on the asymptomatic sides (18%, all neurovascular). In the controls,3 sides (4%, neurovascular on 2 sides and tumor on 1 side) were involved in the compressions of the REZ of the facial nerves. (2) In the 31 cases with the HFS of neurovascular etiology, the offending vessels were the anterior inferior cerebellar arteries in 11 cases (38%), the vertebral artery (VA) single in 5 cases (17%), VA plus posterior inferior cerebellar artery (PICA) in 4 cases(12%) and PICA in 8 cases (25%). (3) The relative risks of microvascular compressions which cause HFS were 37.28. (4) The real microvascular compression and entrapping were only detected on the symptomatic sides of HFS in 14 patients (45%). Conclusions 3D TOF MRA appeared to be the best imaging test for the pathogenesis of HFS now. The major causes of HFS might be different neurovascular compressions in the REZ of the seventh cranial nerve, with real compression, entrapping or tight contact.