Clinical and experimental studies of Bell's palsy.

1型单纯疱疹是贝尔瘫痪的最有可能的原因。我们从贝尔麻痹患者的神经内液和耳肌中证实了HSV-1 DNA的存在，并阐明了HSV-1感染与贝尔麻痹的发病直接相关。我们还通过将HSV接种到小鼠的耳廓，成功地产生了急性和短暂性面瘫，模拟贝尔氏麻痹。本研究利用动物模型和Bell‘s面瘫模型对面神经麻痹的发病机制进行了研究。小鼠模型的组织病理学检查显示，受累的面神经有严重的神经肿胀、炎细胞浸润和空泡变性。面神经干中混杂着完整的、脱髓鞘的和变性的神经。电生理研究表明，瞬目反射中R1潜伏期的时程与面神经麻痹的恢复有很好的平行关系，而Enog的恢复与面瘫相比有延迟的趋势，这些反应通常见于Bell‘s麻痹。部分贝尔氏麻痹患者面神经血流量有不同程度的下降。然而，在没有面瘫的胆脂瘤患者中也观察到了同样的血流量下降。提示单纯疱疹病毒1型感染是贝尔面瘫的主要原因，神经缺血是病毒感染的次要原因。对69例Bell‘s患者应用阿昔洛韦-泼尼松治疗的疗效进行了回顾性分析。总回收率为95.7%。在发病后3天内开始治疗的患者的比率为100%。这些结果表明，早期治疗对于有效的阿昔洛韦-泼尼松治疗贝尔麻痹是必要的。

Herpes simplex type 1 is the most probable cause of Bell's palsy. We have demonstrated the presence of HSV-1 DNA in the endoneural fluid and auricular muscle obtained from patients with Bell's palsy, and clarified that HSV-1infection is directly related to the pathogenesis of Bell's palsy. We have also succeeded in producing an acute and transient facial paralysis, simulating Bell's palsy, by inoculating HSV into the auricle of mice. In the present study, we have studied pathomechanism of facial palsy by using animal model and Bell's palsy. Histopathology of the mouse model demonstrated severe nerve swelling, inflammatory cell infiltration and vacuolar degeneration in the affected facial nerve. Intact, demyelinated, and degenerated nerves were intermingled in the facial nerve trunk. Electro physiological study has demonstrated that the time course of R1 latency in the blink reflex tests paralleled the recovery of the facial nerve paralysis well, whereas ENoG recovery tended to be delayed, compared to that of the paralysis ; these responses are usually seen in Bell's palsy. The blood flow in the facial nerve was decreased to some extent in some patients with Bell's palsy. However, the same decrease of blood flow was noted in patients with cholesteatoma without facial paralysis. These results suggested that viral infection of HSV-1 was the primary cause of facial palsy in Bell's palsy and ischemia of the nerve was secondary to the viral infection. The effect of acyclovir-prednisone treatment was analyzed retrospectively in 69 Bell's patients. The overall recovery rate was 95.7 %. The rate in patients who started this treatment within 3 days after onset was 100 %. These results suggest that early treatment is necessary for effective acylovir-prednisone therapy in Bell's palsy.