半导体激光对豚鼠视网膜电图的影响

目的通过早期的动物实验研究，为应用半导体激光治疗弱视提供能量强度的参考范围。方法取豚鼠90只，雌雄不限，随机分为正常对照组A，2mW激光处理组B，3mW处理组C，4mW处理组D和5mW处理组E，每个处理组根据照射次数的不同又分为每天一次组J，每天两次组K，加对照组共9组。每组实验动物暗适应12h后，进行处理前闪光视网膜电图（flash electroretinogram，fERG）检测。根据各组功率及照射次数的不同，用LL-300型半导体激光弱视治疗仪经瞳孔照射眼底视网膜。实验处理结束时，以同样方法再次进行伍RG，对比处理前后ERG的变化。结果与实验前相比，不同照射功率组间a波振幅变化有统计学意义（P〈0.05），其中C组实验处理后a波振幅值较处理前明显升高，而D纽和E组实验处理后a坡振幅略有降低：b波及N1-P1波振幅改变无统计学意义（P〉0.05）。结论豚鼠视觉感受器细胞对于不同功率照射会产生不同反应，实验前后3mW照射组a波幅值升高，4mW和5mW照射组下降。视网膜其他细胞层并未产生明显的电生理变化。

Observation of the effect of semi-conductor laser on the electroretino-gram of guinea pigs

Objective To establish a frame of reference for setting the power of a semi-conductor laser for future observation and testing in the clinic. Methods Ninety male and female guinea pigs were divided into a normal control group A and four additional groups depending on the power of the laser beam that was used： 2 mW beam, group B, 3 mW beam, group C, 4 mW beam, group D, and 5 mW beam, group E. Except for group A, the others groups were subdivided into team J （one time a day） and team K （two times a day） based on the number of exposure sessions. In all, there were 9 teams, including control group A. Every guinea pig lived under scotopic light levels for 12 h, pupils were dilated with a 1.25% tropicamide-phenylephrine ophthalmic solution and then the guinea pigs were given an injection of 2% chloral hydrate into the abdominal cavity for anesthesia. After that, the pre-experimental flash electroretinogram （ERG） of the guinea pigs was recorded. Then a beam from a semi-conductor laser that was emitted by an LL-300 amblyopia apparatus was passed through the pupils of the guinea pigs＇ eyes. The power of the beam and num- ber of exposure times were in compliance with the protocols used to set up the teams. Exposure times lasted for 3 minutes and continued for 30 days. Then the post-experiment ERG was recorded as it was done earlier. The changes in the ERG recordings were compared. Results There were no mean statistical differences between teams when the fERG amplitude of the b-wave and N1-P1 wave were compared （P〉0.05）. But the change in the a-wave amplitude in group C was statistically different from group D and group E （P〈0.05）. It shows that the amplitude of a-wave had ascended in group C but little descended in group D and group E in post- experiment comparing with pre-experiment. Conclusion There were different responses in the sensitive cells of the retina that depended on the power of the laser beams used in the different groups. This was demonstrated by the ascent of the a-wave in team C