超脉冲CO2激光对豚鼠耳蜗形态学损伤的实验研究

发布时间：2018-04-17 00:06

本文选题：超脉冲CO2激光 + 耳蜗　；参考：《福建医科大学》2010年硕士论文

【摘要】： 【目的】本试验以超脉冲CO2激光为辐射源,对活体豚鼠耳蜗底周骨壁进行开窗,研究激光豚鼠耳蜗底周开窗对耳蜗形态的影响,并与正常对照组进行比较,从而为激光在耳外科手术中的安全应用提供实验性指导依据。【方法】分别以耳后入路和听泡入路解剖4只豚鼠,了解其中耳解剖结构,确定暴露豚鼠耳蜗底周的最佳手术入路。将48只白色红目豚鼠随机分为4组,每组12只。其中3组以不同剂量的超脉冲C02激光对豚鼠耳蜗底周骨壁进行开窗,随后取被照耳作耳蜗基底膜铺片硝酸银染色光学显微镜检查、扫描电镜检查及免疫组化染色检测热休克蛋白70(heat shock protein HSP70)的表达,并与正常对照组进行比较,进而分析激光辐照对耳蜗超微结构的影响,HSP70的表达及在豚鼠耳蜗超微结构损伤机制中的作用。【结果】术后即刻,光镜下观察正常对照组豚鼠耳蜗底回基底膜硝酸银染色未见明显异常；1W、2W、3W组可观察到硝酸银浓染,外毛细胞肿胀,血管纹扩张。术后即刻,正常组和1W组,扫描电镜检查底回毛细胞未见异常；2W、3W组可见底回第2、3排外毛细胞静纤毛显示部分不规则,但毛细胞未见明显丢失。术后2周,2W组扫描电镜检查未见异常；3W组可见底回第2、3排外毛细胞部分排列紊乱、静纤毛显示部分倒伏,毛细胞未见明显丢失,结果同术后即刻。术后6小时,正常对照组豚鼠耳蜗螺旋神经节、基底膜及螺旋韧带等部位HSP70的表达呈弱阳性,1W、2W、3W组豚鼠耳蜗螺旋神经节、基底膜及螺旋韧带等部位HSP70的表达呈阳性至强阳性,且随激光剂量的增大,阳性细胞数及阳性细胞比例逐渐增高,激光3W组与其余组比较有统计学意义(p0.05)。【结论】 1、直接听泡入路手术过程简单,易暴露耳蜗底周,术后并发症少,为豚鼠耳蜗底周开窗的最佳手术入路。 2、低剂量超脉冲C02激光能有效消融耳蜗底周骨壁,且在限定的激光剂量下不会对内耳结构造成损伤,但对内耳功能的影响有待进一步研究。 3、激光豚鼠耳蜗底周开窗能诱发耳蜗热休克反应,使HSP70表达增加,其表达程度与耳蜗超微结构改变有关,HSP70可能发挥保护耳蜗免受损伤的作用。
[Abstract]:[purpose]In this experiment, ultrapulse CO2 laser was used as the radiation source to open the bone wall around the cochlea of living guinea pig. The effect of the fenestration on the cochlea morphology was studied and compared with that of the normal control group.This provides experimental guidance for the safe application of laser in ear surgery.[methods]Four guinea pigs were dissected by posterior ear approach and auditory alveolar approach respectively. The anatomical structure of the middle ear was studied and the optimal operative approach for the exposure of cochlea was determined.Forty-eight white red guinea pigs were randomly divided into 4 groups with 12 in each group.Three groups of guinea pig cochlea were treated with different doses of superpulse CO2 laser to open the bone wall around the bottom of the cochlea, and then the irradiated ears were taken for silver nitrate staining optical microscopy of the basal membrane of the cochlea.The expression of heat shock protein (70(heat shock protein HSP70) was detected by scanning electron microscopy and immunohistochemical staining, and compared with that of normal control group.The effect of laser irradiation on the ultrastructure of cochlea and the expression of HSP70 in guinea pig cochlea were analyzed.[results]Immediately after operation, silver nitrate staining, swelling of outer hair cells and vasodilation in basal membrane of basal gyrus of normal guinea pigs were observed under light microscope.Immediately after operation, in normal group and 1W group, no abnormal hair cells were found in the bottom gyrus of the bottom gyrus. In the 2W 3W group, the static cilia of the 2nd third row of the bottom gyrus were irregular, but the hair cells were not significantly lost.2 weeks after operation, no abnormality was found in the scanning electron microscope in the 2W group. In the 3W group, there was a disorder in the arrangement of the outer hair cells in the 2nd row of the bottom gyrus. The static cilia showed partial lodging, and the hair cells were not obviously lost. The results were the same as immediately after the operation.Six hours after operation, the expression of HSP70 in cochlear spiral ganglion, basement membrane and spiral ligament of guinea pigs in normal control group was weakly positive. The expression of HSP70 in cochlear spiral ganglion, basement membrane and helical ligament of guinea pig cochlear spiral ganglion was strongly positive.With the increase of laser dose, the number of positive cells and the proportion of positive cells increased gradually. Compared with the other groups, the number of positive cells in the laser 3W group was significantly higher than that in the other groups.[conclusion]1. The procedure of direct auditory alveolar approach is simple, easy to expose cochlea fundus, and has less postoperative complications. It is the best operative approach for guinea pig cochlea fundus fenestration.2. Low-dose ultra-pulse CO2 laser can effectively ablation the bone wall around the bottom of cochlea, and the structure of the inner ear will not be damaged under the limited laser dose, but the effect on the function of the inner ear needs further study.3. Laser fenestration induced heat shock response and increased HSP70 expression in cochlea. HSP70 may play a role in protecting cochlea from injury due to the ultrastructural changes of cochlea.
【学位授予单位】：福建医科大学
【学位级别】：硕士
【学位授予年份】：2010
【分类号】：R764

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