Munich Stephan A, Morcos Jacques J
Department of Neurosurgery, University of Miami, Florida.
Oper Neurosurg. 2019 Feb 1;16(2):267-268. doi: 10.1093/ons/opy111.
Hemifacial spasm is characterized by painless and involuntary spasms of the muscles supplied by the facial nerve, most commonly involving the orbicularis oculi. The most common cause of hemifacial spasm is compression of the facial nerve's root by the anterior inferior, or posterior inferior, cerebellar arteries (AICA or PICA). However, in <1% of cases, the compression can be due to a dolichoectatic vertebral artery. Microvascular decompression using Teflon patties may be sufficient when the offending artery is small (eg, AICA or PICA). However, the size and tortuosity of the vertebral artery (especially one that is dolichoectatic) may require a more robust means of decompression (ie, "macrovascular decompression"). In this operative video we demonstrate our technique for managing a patient with hemifacial spasm due to a dolicoectatic vertebral artery. We use a Goretex® (W.L. Gore & Associates Inc, Newark, Delaware) sling secured to the dura of the posterior petrous ridge to suspend the vertebral and posterior inferior cerebellar arteries, thereby decompressing the root entry zone of the facial nerve. Teflon felt pieces are added as a second layer of security. Key steps to this technique include: (1) visualization of the root entry zone, (2) extensive arachnoid dissection to allow adequate mobilization of the vertebral artery, 12 and (3) securing the sling in a trajectory that prevents kinking of the vertebral artery and its branches.
半面痉挛的特征是由面神经支配的肌肉出现无痛性、不自主痉挛，最常累及眼轮匝肌。半面痉挛最常见的病因是小脑前下动脉或小脑后下动脉（AICA或PICA）对面神经根的压迫。然而，在不到1%的病例中，压迫可能是由于椎动脉迂曲扩张所致。当致病动脉较小时（如AICA或PICA），使用特氟龙片进行微血管减压可能就足够了。然而，椎动脉的大小和迂曲程度（尤其是迂曲扩张的椎动脉）可能需要更有力的减压方法（即“大血管减压”）。在这个手术视频中，我们展示了我们治疗因椎动脉迂曲扩张导致半面痉挛患者的技术。我们使用一种戈尔特斯（W.L. Gore & Associates Inc，特拉华州纽瓦克）吊带固定在岩骨后嵴的硬脑膜上，以悬吊椎动脉和小脑后下动脉，从而对面神经根进入区进行减压。添加特氟龙毡片作为第二层保障。该技术的关键步骤包括：（1）显露神经根进入区；（2）广泛的蛛网膜下腔解剖，以使椎动脉能够充分游离；（3）将吊带固定在一个能防止椎动脉及其分支扭结的轨迹上。
