Nd:YAG激光照射对兔面神经损伤的实验研究

Rabbit facial nerve damager after Nd: YAG laser irradiation: an experimental study

目的探讨不同能量密度Nd：YAG连续激光对兔面神经的损伤效应及术后再生情况，为Nd：YAG激光治疗腮腺区深部海绵型血管瘤提供依据。方法根据临床治疗功率，采用5种不同能量密度Nd：YAG激光，分别对28只兔面神经进行照射。结果能量密度＜70J／cm2激光致面神经轻度变性，术后3周功能基本正常;能量密度140J／cm2激光致面神经中度变性;术后3周功能明显下降，6周基本恢复正常;能量密度240J／cm2激光致面神经不可逆损伤。结论Nd：YAG激光的热效应是面神经损伤的重要原因，且程度与能量呈正相关。

Objective To investigate the damage effects of rabbit facial nerve after Nd: YAG laser irradiation. Methods According to therapeutic laser energy density, the facial nerves of 28 rabbits were irradiated by Nd: YAG laser with 5 different laser dosages. Results The facial nerves were functionally intact with mild degeneration histologically at three weeks postoperatively,when the energy density of Nd:YAG laser 10wer than 70J/cm2. In the group with energy density of 140J/cm2, facial nerve functionally impaired with moderate degeneration which rehabilitated within six weeks. While the laser power increased to more than 240J/cm2,irreversible nerve damages happened. Conclusion Laser thermal effect is the main cause of nerve damage,there is a positive correlation between laser dosage and nerve impairment