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目的：探讨微波造成面神经辐射损伤的电生理及病理学特点。方法：６０只ＳＤ大鼠面神经上、下颊支，按２０Ｗ×１０ｓ，２０Ｗ×２０ｓ和２０Ｗ×４０ｓ的辐射剂量，随机分为Ⅰ，Ⅱ，Ⅲ３组。于损伤后即时与４０ｄ做神经电生理学检测；损伤后１，１０，２０，４０ｄ取材，作光镜、电镜观察和轴索计数。结果：损伤后即时，３组的动作电位幅值分别下降了１６．４０％，４１．４５％和８７．４１％，组间差异非常显著（Ｐ＜０．０１）。病理改变表现：Ⅰ、Ⅱ组以雪旺细胞崩解，吞噬细胞浸润和轴突消失为主；超微结构改变为雪旺细胞基底膜破坏，髓鞘变形、崩解。Ⅲ组还见神经束膜的坏死、消失。３组轴索恢复率分别为９６．９７％，８０．０９％和０％。结论：面神经损伤与微波剂量呈正比，当微波＞２０Ｗ×２０ｓ、天线距面神经＜５ｍｍ时，面神经可能发生不可逆损伤。
Objective: To investigate the electrophysiological and pathological features of facial nerve irradiation induced by microwave. Methods: Sixty Sprague Dawley rats were randomly divided into three groups according to their radiation doses of 20W × 10s, 20W × 20s and 20W × 40s. Electrophysiological examination was performed immediately after injury and at 40 days. The lesions were taken at 1, 10, 20 and 40 days after injury for light, electron microscopy and axonal counting. Results: Immediately after injury, the amplitude of action potentials in the three groups decreased by 16.40%, 41.45% and 87.41%, respectively. The differences between the two groups were significant (P <0.01). Pathological changes: Ⅰ, Ⅱ group Schwann cells disintegration, phagocytic infiltration and axonal disappearance of the main; ultrastructure changes Schwann cell basilar membrane damage, myelin deformation and disintegration. Group Ⅲ also see the nerve membrane necrosis disappeared. Axillary recovery rates in the three groups were 96.97%, 80.09% and 0%, respectively. Conclusion: The facial nerve injury is proportional to the dose of microwave. When the microwave is more than 20W × 20s and the antenna is less than 5mm from the facial nerve, the facial nerve may be irreversibly damaged.