骨导听性脑干反应和骨导多频听觉稳态反应在传导性听力损失检测中的应用 △

目的 研究骨导分频率听性脑干反应(BC-chirp-ABR)和骨导多频听觉稳态反应(BC-ASSR)与骨导纯音听阈(BC-PTA)在传导性听力损失患者中的差异和相关性,为临床客观听力诊断及预估主观测听阈值提供参考。方法 对40例单侧传导性听力损失患者分别行掩蔽后的BC-chirp-ABR和BC-ASSR测试,获得反应阈,并与BC-PTA阈值进行相关性分析。结果 在0.5、1、2、4kHz频率,BC-chirp-ABR反应阈分别为(25.0±8.2)、(22.3±6.1)、(18.2±7.6)、(19.7±6.9)dB nHL,BC-ASSR反应阈分别为(30.7±10.1)、(28.3±9.7)、(27.7±9.1)、(27.1±8.6)dB nHL。在上述4个频率,BC-PTA阈值分别为(9.5±6.3)、(10.7±5.7)、(12.8±9.1)、(15.3±4.5)dB HL。Pearson相关性分析显示,BC-chirp-ABR和BC-ASSR反应阈与同频率BC-PTA阈值均具有显著相关性,频率越高相关性越强。结论 BC-chirp-ABR和BC-ASSR能够反映同频率BC-PTA阈值,BC-chirp-ABR和BC-ASSR是较好的评估主观听阈的频率特异性客观测听技术。     

多频稳态在儿童人工耳蜗植入前评估中的应用

回顾分析34例接受人工耳蜗植入术患者的术前检查资料,了解多频稳态诱发电位（auditory steady—state response,ASSR）及听性脑干反应（acoustic brainstem response,ABR）在人工耳蜗植入前听力学评估中的应用。     

CE-Chirp听觉稳态反应检测在听阈评估中的价值

目的探讨CE-Chirp听觉稳态反应(CE-Chirp ASSR)检测在听阈评估中的价值。方法2016年5月~2018年11月对100例(187耳)感音神经性耳聋患者行纯音测听、传统ASSR和CE-Chirp ASSR测试,比较传统ASSR、CE-Chirp ASSR同纯音测听的相关性。结果不同刺激声ASSR在各频率的诱发阈值均大于纯音测听。0.5、1、2、4 kHz频率下CE-Chirp ASSR诱发阈值与纯音测听阈值的绝对差值均小于传统ASSR诱发阈值与纯音测听阈值的绝对差值,差异有统计学意义(P<0.05)。将本组患者各频率下的不同刺激声ASSR诱发阈值与纯音测听阈值进行相关性分析,显示均呈现明显的直线相关趋势(P<0.05)。CE-Chirp ASSR诱发阈值与纯音听阈的相关系数在0.5、1、2、4 kHz频率下均高于传统ASSR诱发阈值和纯音听阈的相关系数。结论CEChirp ASSR检测在听阈评估中更快捷、准确。     

儿童多频听性稳态诱发反应阈值与纯音测听阈值的相关性

目的 分析多频听性稳态诱发反应阈值与纯音测听阚值间是否具有相关性,明确能否应用多频听性稳态诱发反应评估纯音测听.方法 选择60例5～6岁儿童,包括正常听力组20例和听力异常组40例.所有患者先行纯听测听检查,然后口服10%水合氯醛镇静睡眠后行多频听性稳态诱发反应检测.根据纯音测听结果,将听力异常组的患儿分为轻度聋组、中度聋组和重度聋组,并将结果分别与其多频听性稳态诱发反应阈值进行比较,分析不同频率处的听力阈值情况及其相关性.结果 听力正常组及轻度聋、中度聋患儿纯音测听阈值与多频听性稳态诱发反应阈值差异均有统汁学意义(P＜0.05),听力正常儿童多频听性稳态诱发反应阈值比纯音测听阚值高20～25 dB HL,轻度聋组约高10 dB HL,中度聋组高10～20 dB HL;重度聋组两者基本一致,且两者成正相关(r=0.837,P＜0.05).结论 多频听性稳态诱发反应阈值与纯音测听阈值之间具有相关性,可以用多频听性稳态诱发反应评估纯音测听.(中国眼耳鼻喉科杂志,2008,8:362-363)     

噪声影响下纯音诱发听性脑干反应的改变

目的 观察噪声影响下纯音诱发听性脑干反应(ABR)的改变.方法 将10只成年南美栗鼠随机平均分为两组,分别暴露强度为105 dB SPL窄带噪声,中心频率4 kHz,2h或5h.噪声暴露前、后1h、2周及4周,测试动物对短纯音声音刺激(1、2、4、8、12以及16 kHz)诱发的听神经复合动作电位(CAP)和ABR,并结合耳蜗毛细胞的损害程度和范围进行分析.结果 2h和5h的窄带噪声暴露造成南美栗鼠不同程度和范围的耳蜗毛细胞损害.与毛细胞损害部位相对应频率的CAP及ABR阈值在暴露噪声后均出现不同程度的提高.噪声暴露后4周,尽管某些动物的CAP已经发生了不可逆性永久阈移,但在某些短纯音频率诱发的ABR阈值却呈现部分恢复,甚至在个别动物的CAP测试波形中引出了低于CAP阈值的ABR波形成分.结论 中枢听觉功能的重组在一定条件下可能促进脑干听觉神经元提高感知因周边耳蜗损害而引起微弱听觉输入信号的敏感性.     

Electrical activity in visual cortex associated with combined auditory and visual stimulation in temporal sequences known to be associated with a visual illusion

When a subject views a visual stimulus paired with a brief click, a second click occurring approximately 80 ms later produces the hallucination of a second visual stimulus. We have used combinations of visual and sound stimuli to evoke cortical activity and have recorded the associated event-related potentials. We have recorded EPs in a conventional manner, and have calculated from multichannel recordings the Laplacian derivations to determine if the currents were generated in primary visual cortex. Clicks alone do not cause significant activity in V1, but if paired with pattern stimulation, modify the evoked potential. The timing of this extra activity almost certainly excludes "feed back" activation from higher centres, and can most simply be explained if sound-activated thalamo-cortical input can rapidly produce extra activity in 'primed' visual cortex. This finding has general implications for cortical function, for the generation of the hallucination and for 'blindsight'.     

年龄对屈光不正性弱视儿童图形视觉诱发电位的影响

目的 分析屈光不正性弱视儿童图形视觉诱发电位（PVEP）检测结果的特点及年龄对其的影响.方法 回顾性系列病例研究.等效球镜为远视的屈光不正性弱视患儿92例（184眼）,按最佳矫正视力0.8～0.6、0.5～0.2、≤0.1三个级别分为轻度弱视组108眼,中度弱视组65眼,重度弱视组11眼.每组又以6岁为界进行分组,分为＜6岁组和≥6岁组.采用视觉电生理检查系统检测PVEP,对弱视组间差异行单因素方差分析,同一程度弱视组中的不同年龄组间行独立样本t检验,比较不同弱视程度组间及不同年龄组间P100波潜伏期（LP100）及振幅（AP100）的差异.结果 随弱视程度加重,PVEP的LP100延长,三组间差异有统计学意义（F=151.30,P＜0.01）,两两间差异均有统计学意义（P＜0.01）.三组间AP100差异有统计学意义（F=13.59,P＜0.05）,两两比较示,重度组的AP100明显较其余两组低,差异有统计学意义（P＜0.01）,中度组较轻度组低,但差异无统计学意义.轻度组中,年龄≥6岁组与＜6岁组比较,LP100明显延长,AP100降低,差异有统计学意义（t=5.08、7.45,P＜0.01）;中度组也呈类似表现（t=4.68、4.27,P＜0.01）;重度组结果类似,但由于例数少,未进行统计分析.结论 PVEP的LP100、AP100可作为衡量儿童屈光不正性弱视严重程度的客观指标,同时对结果进行分析时应充分考虑年龄的影响.     

Transient pattern Visual Evoked Potentials in children with Down''s syndrome

Visual acuity and contrast sensitivity are lower in children with Down's syndrome than in those developing normally. In many cases, this difference might be accounted for by the relatively high incidence of ocular abnormalities (including refractive error and strabismus) in Down's syndrome. However, abnormal spatial vision persists in children with Down's syndrome in the absence of ocular abnormality, suggesting that abnormal retino-cortical visual processing explains reduced visual function in this group. The aim of the present study was to assess retino-cortical function in children with Down's syndrome by recording transient visual evoked potentials (VEPs) in response to pattern stimuli. Responses from children with Down's syndrome were compared with those recorded from children developing normally. Response latency is similar in the two groups, but morphology differs, with the N75 component being clearly present in the normal responses, but diminished or undetectable in responses from children with Down's syndrome. Our findings may suggest a cortical abnormality specific to the source of the N75 component of pattern-reversal achromatic VEPs.     

一种电脑软件弱视治疗系统治疗儿童弱视的临床观察

目的 探讨一种电脑软件弱视治疗系统治疗儿童弱视的可行性并观察其疗效.方法 前瞻性病例对照研究.51例（86眼）弱视儿童纳入本研究,分为实验组（24例44眼）和对照组（27例42眼）.实验组采用一套根据现有弱视治疗理论设计的电脑软件弱视治疗系统进行治疗.对照组采用传统的门诊弱视治疗方法——氦氖激光照射以及海丁格光刷进行治疗.治疗1个疗程后随诊观察3个月到半年,对两组的有效率及实验组治疗前后弱视眼图形视觉诱发电位（PVEP）检查结果进行比较.相关数据采用独立样本t检验,x2检验和Fisher确切概率法进行统计分析.结果 实验组总有效率为73％,对照组为57％,两组总有效率差异无统计学意义.对于中度弱视患儿,实验组治疗有效率为77％,对照组为42％,差异有统计学意义（x2=5.662,P＜0.05）.对于屈光不正性弱视患儿,实验组的治疗有效率为74％,对照组为44％,差异有统计学意义（x2=4.337,P＜0.05）.实验组患儿治疗1个疗程后,PVEP检查以1°、30′及15′视角刺激时,平均潜伏期均较治疗前缩短,但治疗前后差异无统计学意义.平均振幅均较治疗前上升,治疗前后差异有统计学意义（t=2.11、2.47、2.34,P＜0.05）.结论 该电脑软件弱视治疗系统功能全面,可作为儿童弱视治疗的一种有效辅助手段.     

Chromatic VEP in children with congenital colour vision deficiency

Visual evoked potentials to chromatic stimulus (cVEP) are believed to selectively test the parvocellular visual pathway which is responsible for processing information about colour. The aim was to evaluate cVEP in children with red‐green congenital colour vision deficiency. VEP responses of 15 colour deficient children were compared to 31 children with normal colour vision. An isoluminant red‐green stimulus composed of horizontal gratings was presented in an onset‐offset manner. The shape of the waveform was studied, as well as the latency and amplitude of positive (P) and negative (N) waves. cVEP response did not change much with increased age in colour deficient children, whereas normative data showed changes from a predominantly positive to a negative response with increased age. A P wave was present in 87% of colour deficient children (and in 100% of children with normal colour vision), whereas the N wave was absent in a great majority of colour deficient children and was present in 80% of children with normal colour vision. Therefore, the amplitude of the whole response (N‐P) decreased linearly with age in colour deficient children, whereas in children with normal colour vision it increased linearly. P wave latency shortened with increased age in both groups. cVEP responses differ in children with congenital colour vision deficiency compared to children with normal colour vision.     

Visual electrophysiology in children with tumours affecting the visual pathway Case reports

In 9 children (8–14 years of age) with orbital, suprasellar or postchiasmal tumours, visual loss was studied by visual electrophysiology in relation to ophthalmologic and neuroimaging findings. Pattern electroretinography (PERG) and pattern visual evoked potentials (PVEP) to full and half-field pattern-reversal stimulation were recorded and PERG and PVEP changes were related to the tumour location. PERG wave P50 attenuation was found associated with the central retinal dysfunction in the child with orbital rhabdomyosarcoma; PVEP wave P100 delay was associated with the optic nerve dysfunction in a child with retrobulbar chondrosarcoma and in a child with optic nerve glioma; PVEP wave P100 asymmetry was associated with the crossed fibers dysfunction in a child with hypothalamic germinoma, and PVEP wave P100 uncrossed asymmetry was associated with postchiasmal dysfunction in children with postchiasmal tumours (one with pilocytic astrocytoma and two with angioma). On the other hand, normal PERG suggested that there was no central retinal dysfunction in a child with pleomorphic adenoma of the lacrimal gland, and normal PVEP to full and half-field stimulation excluded visual pathway dysfunction at the chiasm in a child with suprasellar arachnoidal cyst. Follow-up was useful in indicating whether visual dysfunction was progressive or not. We conclude that PERG and PVEP findings contributed to understanding whether the dysfunction originated was at the retina, in the optic nerve, chiasm or postchiasmal pathway.