摘要：
Objective To estabhsh an ischemic model of intratemporal facial nerve (IFN) via the mastoid process approach.Methods From February,2015 to December,2015,45 SD rats were divided randomly into an operation group (n=35) and a shame group (n=10) in random,the right side facial nerve was used for the operation and the left side served as the control in both groups.Establish the IFN ischemia model by interrupting the petrosal artery through the mastoid process approach.Facial nerve function were evaluated at the 12h and everyday postoperatively for 28 days.The degree of IFN swelling were studied by taking paraffin sections of the decalcified temporal bone containing the IFN instantly and at the 1st,3rd,7th,14th and 21st days postoperatively.Then calculated the ratio of the cross-sectional area of the IFN and the facial canal (FN/FC).The data of behavior assessment and FC/FN were analyzed using ANOVA.Twenty-eight days after the insult,took continuous sections of brainstem containing facial nucleus,then counted the number of the facial neurons.At last,analysed the results of both operation and control sides in each group by using the student-t test.Results Facial nerve paralysis developed at 12 hour after surgery,then continued deteriorated till the 7th day.By the 28th day postoperatively,all rats in surgery group recovered and data showed no significance statistically when compared with the shame group (P＜0.05).From the value of FN/FC in different groups,the nerve were found swelling in the facial canal was increasing from the 1st postoperatively and reach the peak value at the 7th day after surgery.By the 21st day,the FN/FC come to steady but remain significant statistically when compared with the contralateral side(P＜0.05).In the operation group,facial neurons of injury side exhibited significantly loss [(41.5±3.8)％] when compared with the shame group [(98.1±4.0)％](P＜0.05).Conclusion Rats with petrosal artery interrupted exhibited significant deficits.This approach involved less tissue injury,studies on the mechanisms and therapy could become more reliable using this approach.%目的 建立一种组织损伤轻、入路更便捷、更符合临床的面神经缺血大鼠模型. 方法 从2015年2月至12月,依据随机数字表将45只成年SD大鼠随机分为手术组(n=35)和假手术组(n=10).手术组采用耳后切口,经乳突入路暴露并阻断岩动脉.假手术组仅暴露岩动脉,不予阻断,两组均取左侧作为自身对照组.于术后12h及连续28 d从瞬目反射、触须摆动情况对面神经功能进行观察与评价;于术后即刻,第1、3、7、14、21天共6个时间点(每个时间点5只)取含有面神经的颞骨进行切片,计算含膝状神经节段面神经干与面神经管横切面面积之比.面神经功能和面神经肿胀程度均使用单因素方差分析,不同时间点之间比较使用LSD法进行比较;面神经功能稳定后取含有面神经的脑干进行连续切片,计算双侧面神经元计总数,对各组数据采用t检验进行统计学分析,P＜0.05为差异有统计学意义. 结果 ①手术组术后12 h即观察到面瘫,第7天达到高峰,后逐渐缓解,至第28天时面神经功能基本恢复至术前水平,与假手术组相比差异无统计学意义(P＞0.05).②损伤侧术后1d即出现面神经干肿胀,至第7天达到高峰,第21天时趋于稳定,但与对侧相比,仍存在面神经于肿胀(P＜0.05).③至面神经功能稳定时,手术组和假手术组面神经元存活率分别为(41.5±3.8)％和(98.1±4.0)％,缺血面神经干侧面神经元数量明显较少(P＜0.05). 结论 采用乳突小泡入路阻断岩动脉后.出现了较为典型的面神经损伤表现,所得数据稳定.此模型对组织损伤较小,采用此模型进行面神经膝状神经节段缺血损伤机制及治疗等方面研究,获得的结果将更为可靠.
