Changes of blood supply after intracanal decompression of the facial nerve

关于周围性面瘫手术减压的价值一直存在争议。我们一直从事面瘫的品鉴与治疗研究。手术治疗严重面瘫的效果不如预期的好。在基金的支持下，我们进行了一系列的实验和临床研究。我们以往的研究表明，面神经间质液压力完全依赖脑脊液压力，甘露醇可以降低面神经间质压力。我们将研究扩展到改善面瘫的治疗。采用阻断岩大动脉血流的方法制备缺血性面瘫动物模型。Lesar多普勒监测面神经血流显示，甘露醇给药后缺血性面瘫患者血流减少。对豚鼠面神经缺血的组织病理学研究表明，甘露醇使面神经间质水肿减轻。甘露醇可以防止神经退化。我们的临床研究还表明，甘露醇对早期贝尔氏麻痹患者在模仿运动恢复后的联合运动是有效的。有一些贝尔麻痹患者即使使用甘露醇减压法也需要手术减压。传统的电生理测试，如ENOG，对选择手术病例无效。面神经反激反应可监测豚鼠缺血性麻痹的部位、程度和恢复期。作者强调，准确检测面神经病变和早期用甘露醇进行神经减压对提高面神经麻痹的治疗效果至关重要。

There has been contravergy about the value of surgical decompression in cases of peripheral facial palsy. We have been engaged in researches on tasting and management 'of facial palsy. Outcomes of the surgical intervention with cases of severe facial palsy is not excellent as expected. Supported by the grant, we performed series of experimental and clinical studies. Our previous studies showed that interstitial fluid pressure of the facial nerve totally depended on CSF pressure, and that the interstitial pressure could be reduced by administration of mannitol.We extended the studies to improve treatments of facial palsy.We made an animal model of ischemic facial palsy by interrupting blood flow of the great petrosal aretery. Lesar doppler monitoring of blood flow of the facial nerve showed that decreased blood flow in ischemic facial palsy recovered after administration of mannitol. Histopathological studies of the ischemic facial nerve in guinea pigs showed that interstitial edema decreased after administration of mannitol. Mannitol prevented nerve degeneration of the nerve. Our clinical study also showed that mannitol was effective 'in early cases of Bell's palsy to prevent synkinesis after recovery of mimic movement.There are cases with Bell's palsy which need surgical decompression even with the use of mannitol decompression method.Conventional electrophysiological testings, such as ENOG, are not effective for selecting surgical cases. The site, degree, and recovering phase of the ischemic palsy could be monitored by antidromic facial nerve response in guinea pigs.The authors stress that accurate testing of the facial nerve lesion with antidromic response and early intracanal decompression of the nerve with mannitol is important to improve therapeutic results of facial palsy.