声诱发短潜伏期负电位（ASNR）的引发策略及精确来源定位研究

Acoustically evoked Short Latency Negative Response (ASNR) is a negative potential at 3ms when profound hearing loss ears are exposed to intense sound stimulation. Our researches have recorded ASNR on deafened guinea pig and normal human, the end organ and neural origin are the saccule and the vestibular nuclei respectively. The vestibular nuclei are a complex of inner, lateral, superior and inferior nucleus,the sub-nucleus origin of ASNR and the development of its unique V-shaped negative waveform have not been studied and elucidated. These questions are to be discussed through extracellular record and precise electrolytic lesion to every vestibular sub-nucleus combined with concurrent ASNR record. ASNR is an objective test for vestibular function, however, it is hard to elicit due to the overlap of ABR waves in normal ears. To collect ASNR with optimized strategy, animal and human studies are to be conducted through air-conductive and bone-conductive white noise mask in order to erase the overlapping ABR. Based on the fact that ABR is a complex of ABR and a vestibular potential of ASNR, it is not pure enough to evaluate auditory pathway and need to be modified by ABR-ASNR=”Pure”ABR. Same subject, same ear, same stimuli are essential conditions for collecting ABR and mask-ASNR before subtraction of the two waveforms. Animal experiments by means of nucleus electrolytic lesion are also necessary to verify the difference between the original and“Pure”ABR.

声诱发短潜伏期负电位（ASNR）为重度感音性聋耳在强声刺激时出现的潜伏期约3ms的负电位。本课题组已从豚鼠及人类引出ASNR 波，验证其责任终器是球囊，来源为前庭神经核。而前庭神经核为多亚核复合体，包括前庭内侧核、外侧核、上核和下核，ASNR的来源亚核且其独特的V形负波的成因尚无研究解明。拟通过声刺激下豚鼠前庭各亚核的细胞外电位记录和精确亚核破坏，结合同步体表ASNR记录进行探讨。由于正常耳存在ABR波形重叠干扰而无法引出ASNR，限制了临床应用。拟对动物及人类，分别通过气导及骨导白噪声掩蔽消除ABR干扰的策略，引发ASNR并使之成为有临床价值的前庭电位。基于ABR混有来自前庭通路的ASNR的事实,提出ABR-ASNR=“纯”ABR的概念以消除两波形干扰误差，完善ABR对听觉传导通路的评估。尝试对同一个体、同一耳、同一刺激强度测得ABR及掩蔽ASNR并减法运算得出，并探讨科学性和应用价值。

声诱发短潜伏期负电位（ASNR）为重度感音性聋耳在强声刺激时出现的潜伏期约3ms的负电位，其责任终器是球囊，来源为前庭神经核。由于ASNR及ABR的产生条件完全一致，二者互相叠加，本课题探索在正常听力人类和动物消除ABR干扰，并引发ASNR的策略。反之，还在此基础上屏蔽ASNR的影响而获取纯ABR。通过动物和人实验得出掩蔽方式可以近乎完全屏蔽了听觉通路，其中动物的ASNR引出率高于药毒法，以此模拟了重度感音性聋。通过自制同侧掩蔽模型，发现气导耳罩式同侧白噪声掩蔽是一种较为良好的ASNR诱发策略，在正常人成功掩蔽ABR并诱发出ASNR。收集正常人ASNR数据可用于指导诊断ASNR技术的建立。ABR纯化操作屏蔽了来自前庭通路的电位叠加，使得II波还原增大，故此ABR波形分化有所改变。由于ASNR对I-V波潜伏期受影响不明显，对动物ABR波间期和阈值判断尚无影响。对比原始ABR和“纯化”ABR，验证了ABR和ASNR波相互叠加的猜想，纯化操作可以较为真实的反映ABR波的振幅和潜伏期情况。通过对豚鼠前庭亚核精确定位研究，获得各亚核精确坐标理论数据，通过电毁损及电位记录方法验证亚核坐标并予以修正，记录包括前庭内侧核、外侧核、上核和下核的各亚核的声诱发前庭电位，在前庭内侧核、外侧核可记录到声诱发前庭亚核电位。在获取更多前庭亚核电位数据后，分析ASNR的来源亚核且其独特的V形负波的成因。