脑干听觉诱发电位对重症手足口病神经系统损害的早期诊断价值

目的 探讨脑干听觉诱发电位（brainstem auditory evoked potential,BAEP）对手足口病重症病例神经系统损害的早期诊断价值.方法 本研究通过对297例手足口病患儿进行BAEP检测,之后按照严重程度分级及年龄进行分组比较,手足口病普通病例、年龄＜3岁为A组（n=80）,重症病例重型、年龄＜3岁为B组（n=94）,普通病例、年龄≥3岁为C组（n=38）,重症病例重型、年龄≥3岁为D组（n=85）.回顾性分析各组脑电图（electroencephalogram,EEG）、头部MRI的检测结果,并与BAEP结果进行比较.结果 （1）B组BAEP异常率（18/94,19.15％）高于A组（3/80,3.75％）,D组BAEP异常率（13/85,15.29％）高于C组（1/38,2.63％）,差异有统计学意义（P＜0.05）.（2）B组EEG异常率偏低（2/94,2.13％）,A组无一例EEG异常.（3）D组EEG异常率（49/85,57.65％）高于C组（6/38,15.79％） （P ＜0.05）,且高于D组BAEP异常率.（4）B组MRI异常率（9/94,9.57％）高于A组（1/80,1.25％）（P＜0.05）,D组MRI异常率（9/85,10.59％）高于C组（0）.（5）全部手足口病重症病例重型患儿的BAEP异常率（31/179,17.32％）高于MRI异常率（18/179,10.06％） （P＜0.05）.结论 BAEP检测可为手足口病重症病例神经系统损害的早期诊断提供客观依据.     

新生儿高胆红素血症脑干听觉诱发电位检测的临床意义

目的观察高胆红素血症对新生儿脑干听功能的影响。方法应用脑干听觉诱发电位（BAEP）检查90例足月新生儿高胆红素血症（高胆组）及30例正常对照组。结果与对照组比较高胆组血清胆红素水平与PL（各波峰潜伏期）或IPL（各波峰间期）时间异常率密切相关，胆红素水平越高，PL或IPL异常率越高。血清总胆红素浓度超过256．5μmol／L，可出现PL及IPL异常改变。高胆组BAEP各波的PL和IPL延长，与对照组比较差异有显著性。结论足月儿血清总胆红素浓度超过256．5μmol／L，中枢神经系统即可受到损害，应给予积极治疗。BAEP对了解新生儿听觉和脑干功能障碍有意义。     

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目的分析重症及危重症手足口病患儿脑脊液常规和生化检查结果,指导早期识别危重症手足口病患儿。方法回顾性分析2010年4至10月中国医科大学盛京医院感染科及PICU收治的197例重症和37例危重症手足口病患儿的一般临床资料和脑脊液常规生化检查,对两组结果进行分析比较。结果两组脑脊液异常总数差异有统计学意义(P<0.05),白细胞蛋白均增高患儿数量、仅白细胞增高患儿数量、仅蛋白增高患儿数量差异均有统计学意义(P<0.05)。重症组患儿脑脊液蛋白增高48例,占24.37%;危重症组患儿脑脊液蛋白增高16例,占43.24%。两组间比较差异有统计学意义(P<0.05)。两组间脑脊液白细胞数差异无统计学意义(P>0.05),而蛋白定量差异有统计学意义(P<0.05)。结论脑脊液蛋白明显增高或者单纯蛋白增高而白细胞正常的重症手足口病患儿更容易发展为危重症;危重症患儿脑脊液蛋白显著增高提示免疫机制在危重症患儿神经系统损伤中可能有重要作用。     

新生儿高胆红素血症患儿脑干听觉诱发电位及血清神经元特异性烯醇化酶变化及临床意义

目的通过对新生儿高胆红素血症患儿脑干听觉诱发电位（BAEP）及血清神经元特异性烯醇化酶（NSE）检测，评估高胆红素血症对新生儿听神经损伤。方法56例血清胆红素大于220．5μmol／／L的新生儿为高胆红素血症组（简称高胆组），血清胆红素小于220．5μmol／／L的49例足月儿为对照组，分别进行BAEP、NSE检测。结果高胆组新生儿BAEP的Ⅰ、Ⅲ、Ⅴ波绝对潜伏期（PL）、峰间潜伏期（IPL）均明显延长，与对照组比较，差异有显著性意义（P〈0．01）；高胆组新生儿NSE明显高于对照组，差异有显著性意义（P〈0．01）；NSE水平与BAEP的Ⅴ波反应阈值呈正相关（r=0．65，P〈0．01）。结论高胆红素血症可导致新生儿听神经损伤；BAEP和NSE对其神经损伤有较高的敏感性，可作为监测指标。     

流行性腮腺炎累及中枢神经系统患儿脑干 听觉诱发电位的观察与分析

目的分析并探讨流行性腮腺炎累及中枢神经系统(CNs)患儿脑干听觉诱发电位(BAEP)的变化规律和应用价值。方法对473例流行性腮腺炎累及CNS患儿按脑脊液和脑电图的不同变化分三组，应用肌电/诱发电位仪进行BAEP描记分析。结果473例BAEP检测异常78例，总异常率为16.5％(78/473)，其中脑电图异常组BAEP异常14例，异常率14.7％(14/95)，脑脊液异常组BAEP异常25例，异常率17.4％(25/144)，脑电图与脑脊液均异常组BAEP异常39例，异常率16.7％(39/234)，三组之间相互比较，均为P＞0.05，无显著性差异。BAEP各波异常中I波PL延长异常累计15例次(3.17％)，其余各波PL延长、IPL延长累计共73例次(15.43％)，两者比较P＜0.01差异有极显著性。473例患儿有耳聋4例(0.85％)。结论流行性腮腺炎累及CNs出现BAEP异常多见，但耳聋不多，其BAEP异常率与脑电图及脑脊液改变的关系不大，脑干水平听觉传导通路的损害发生率高于耳蜗和听神经，但为可逆性损害，耳蜗和听神经损害可导致耳聋常为不可逆性，流行性腮腺炎累及CNS时应做BA-EP筛查。     

新生儿高胆红素血症听觉诱发电位检测的临床意义

目的 通过对新生儿高胆红素血症患儿进行胞干听觉诱发电位(BAEP)检测，评估高胆红素血症在未发生核黄疸时对脑损害及听力的影响。方法 对新生儿高胆红素血症患儿入院后进行脑干听觉诱发电位的测定。结果 49例高胆红素血症患儿中异常BAEP发生率为37％(18／49例)，表现为各波潜伏期(PL)及波间潜伏期(IPL)的延长和听阈值的增高，听阈值随胆红素浓度的增高而增高，经治疗后黄疸消退，脑干听觉诱发电位大部分恢复正常。结论 高胆红素血症对新生儿可造成听力损害，BAEP是检测高胆红素血症患儿听力筛查的重要手段之一。     

41例小儿散发性病毒性脑炎脑干听觉诱发电位的观察

本文应用BAEP对41例小儿散发性病毒性脑炎进行测试,结果15例(35%)PL,LPL及波幅有不同程度异常,提示脑干听神经通路受累。发现BAEP异常与本症患儿意识障碍程度相关,9例昏迷病儿均有显著BAEP异常,但与颅内压增高无明显关系。29例有颅内压增高者只有7例有不同程度BAEP异常。作者指出,BAEP可作为小儿散发性病毒性脑炎颅内病损的客观指标,更因其敏感、稳定、无损伤和操作简便,值得推广应用。     

窒息新生儿脑干听觉诱发电位与血清神经元特异性烯醇化酶的相关性分析

目的：通过研究窒息患儿脑干听觉诱发电位（BAEP）异常与神经元特异性烯醇化酶（NSE）的相关性,探讨NSE对早期了解窒息患儿听神经损害的临床意义和应用前景。方法：选择该院窒息足月新生儿52例作为研究组,根据Apgar评分以及是否合并缺氧缺血性脑病(HIE)分为单纯轻度窒息组23例、单纯重度窒息组15例和窒息合并HIE组14例。采用双盲试验在生后7 d同一时间检测BAEP和NSE,初次BAEP检测异常者在生后3个月同一时间进行第2次BAEP和NSE检测。正常足月新生儿30例作为对照组。结果：窒息患儿两次听力损伤检出率分别为50.0%,21.2%。BAEP两次检出异常率,重度窒息组(63.3%,26.3%)与轻度窒息组(36.9%,5.9%)比较,差异均有显著性意义(P<0.05),HIE组(57.1%,31.3%)与重度窒息组比较差异无显著性意义。各研究组NSE水平均明显高于对照组(P<0.01),重度窒息组为26.70±2.34 μg/L明显高于轻度窒息组的17.18±3.16 μg/L,差异有显著性意义(P<0.01),HIE组为27.00±2.01 μg/L,与重度窒息组比较差异无显著性意义。BAEP异常组NSE水平为25.69±4.12 μg/L高于BAEP正常组的17.15±3.09 μg/L(P<0.01),NSE水平随着V波反应阈值的增高而增高(P<0.05)。结论：血清NSE水平与BAEP密切相关,可作为早期评估窒息患儿听神经损害和判断预后的指标之一。     

晚婴型脑白质营养不良诱发电位改变及诊断价值探讨

目的探讨晚婴型异染性脑白质营养不良(MLD)患儿脑诱发电位改变特点及应用价值.方法对6例MLD患儿进行了脑干听觉诱发电位(BAEP)和正中神经体感诱发电位(MNSEP)测试,并与头颅CT结果比较.结果6例MLD患儿BAEP和MNSEP结果均异常,BAEP异常主要包括Ⅰ波潜伏期延长、Ⅰ～Ⅲ和Ⅰ～Ⅴ峰间期延长;MNSEP异常主要有N9波低平、波潜伏期延长或波形消失,N9～N13和N13～N20峰间期延长,而N20波幅改变不明显.结果还表明,诱发电位的异常早于头颅CT结果.结论诱发电位较早地反映患儿神经传导功能障碍,可以作为无创性早期诊断手段.     

儿童偏头痛脑干、视觉诱发电位及经颅多普勒超声的检测

目的 为探讨儿童偏头痛发作期和间隙期脑干、视觉通路及血管功能异常。方法 本文采用诱发电位(BAEP,VEP),经颅多普勒(TCD)检测了30例儿童偏头痛患者。结果 偏头痛发作期BAEP,VEP,TCD异常率分别为47％,77％和83％。BAEPⅠ,Ⅲ,Ⅴ波潜伏期及Ⅲ-V峰间期延长。VEP双侧偏头痛患者P100潜伏期延长,波幅(N75～Pl00)明显增高。TCD发现MCA,ACA在头痛侧平均血流速度明显增快。结论 上述结果表明偏头痛患儿有视觉和脑干传导功能障碍及血管功能改变。     

Term neonates receiving intensive care at high risk of brainstem auditory impairment

Functional integrity of the auditory brainstem was examined using maximum length sequence brainstem auditory evoked response in 72 term neonates who were receiving intensive care. Compared with normal term controls, the neonates receiving intensive care showed an increase in wave V latency and I to V and III to V interpeak intervals of the response. Wave V latency was significantly increased at very high click rates 455 and 910/s. I to V and III to V intervals were significantly increased at all 91 to 910/s, particularly 455 and 910/s, while I to III intervals were slightly increased. III to V/I to III interval ratios were increased at 455 and 910/s clicks. The slopes of wave V latency-rate, I to V interval-rate, III to V interval-rate and III to V/I to III-interval-ratio-rate functions were significantly steeper than in normal controls. These abnormalities suggest that neonates receiving intensive care are at high risk of brainstem, mainly more central regions, auditory impairment. The MLS BAER abnormalities and brainstem auditory impairment might be the result of collective adverse effects, produced by more than one perinatal risk factor.     

Brainstem auditory evoked responses in very low birthweight infants with chronic lung disease.

Very low birthweight (VLBW) infants who had prolonged oxygen dependence due to chronic respiratory problems, typically neonatal chronic lung disease (CLD), are at high risk of neurodevelopmental impairment. To assess the effect of CLD on neonatal auditory function we studied brainstem auditory evoked response (BAER) in VLBW infants who suffered CLD but no other major perinatal complications or problems. At 37-42 week postconceptional age, the latencies of waves I, III and V in CLD infants were all significantly longer than in normal term infants (all p<0.001). The differences between CLD infants and the term controls were greater for the later waves than for the earlier waves. Abnormally prolonged wave latency (>2.5 SD of the mean measurement) was seen in 7 (21.2%) CLD infants for wave I, suggesting peripheral auditory impairment, 8 (24.2%) for wave III and 14 (42.4%) for wave V. I-V interval in CLD infants was significantly longer than in the term controls (p<0.001). Seven (21.2%) infants had abnormally prolonged I-V interval, suggesting brainstem or central auditory impairment. Of these infants, 2 had both prolonged wave latencies and prolonged I-V interval, suggesting both peripheral and central auditory impairment. Similar abnormalities were found in CLD infants when compared with the BAER in birthweight- and age-matched healthy VLBW infants without CLD. CONCLUSION: Neonatal auditory function is impaired, both peripherally and centrally, at term age in VLBW infants who suffer neonatal CLD.     

Brainstem auditory response findings in late preterm infants in neonatal intensive care unit

Aim: To examine brainstem auditory function at term in late preterm infants admitted to neonatal intensive care unit (NICU). Methods: Fifty‐two preterm infants, born at 33–36 week gestation, were recruited in an NICU and were studied at term using brainstem auditory evoked response (BAER). Results: Compared with normal term infants, BAER wave V latency in the NICU preterm infants was increased at 51 and 91/sec (p < 0.05, 0.05). Intervals of III–V and I–V were increased at all 21, 51 and 91/sec clicks (p < 0.05–0.01), which was more significant at higher than lower rates. Interval ratio of III–V/I–III was increased significantly at 51 and 91/sec (p < 0.05 and 0.01). Wave I and III latencies and I–III interval did not differ significantly from normal controls at any click rates. All amplitudes of waves I, III and V amplitude tended to be reduced at higher rates, while wave I amplitude was reduced significantly at 91/sec clicks. Conclusion: There were BAER abnormalities in the NICU late preterm infants, suggesting compromised brainstem auditory function. Compared with a basically normal BAER in low‐risk late preterm infants previously reported, the abnormalities suggest that perinatal problems or complications adversely affect the late preterm auditory brainstem.     

手足口病并发脑干脑炎19例临床分析

目的总结广东地区手足口病并发脑干脑炎患儿的临床特征,为手足口病并发脑干脑炎的诊断和治疗提供依据。方法收集2008年5～7月诊断为手足口病并发脑干脑炎患儿的临床资料,分析临床表现、实验室检查、神经电生理检查、影像学检查、治疗及转归等特征。选择同期诊断为手足口病并发病毒性脑炎的患儿作为对照组,进行脑干脑炎危险因素的单因素和多因素Logistic回归分析。 结果19例手足口病并发脑干脑炎患儿进入分析。①临床表现：19例患儿均有发热和皮疹;神经系统症状多见于肢体震颤（15例）,眼球异常运动（游动或上翻）（12例）,烦躁和惊恐（8例）;脑神经损害多见于单侧脑神经损害（14例）,舌咽和迷走神经麻痹（9例）。15例出现呼吸衰竭,3例出现肺出血。②实验室检查：外周血WBC升高8例;血糖在正常范围;脑脊液压力升高4例。③神经电生理检查：8例EEG异常,14例脑干听觉诱发电位（BAEP）异常。④影像学检查：3例胸部X线检查提示双肺渗出性病变;15例行头颅CT检查均未见异常;3例头颅MRI检查提示脑干异常信号病灶。⑤转归：2例死于中枢性呼吸和循环衰竭,余17例治愈出院,随访6个月未见神经系统症状。⑥单因素Logistic回归分析显示,肢体震颤、呼吸节律改变、呼吸衰竭、眼球异常运动（游动或上翻）、饮水呛咳、口角歪斜、舌体震颤、末梢循环不良、交叉瘫及BAEP异常与脑干脑炎的发生有关;多因素Logistic回归分析显示,肢体震颤和眼球异常运动（游动或上翻）和BAEP异常是手足口病并发脑干脑炎的危险因素（OR分别为436.9,52.2和93.5）。 结论外周血WBC、血糖以及脑脊液检查对手足口病并发脑干脑炎的诊断不具有特异性。手足口病患儿如出现肢体震颤、眼球异常运动（游动或上翻）等症状,应警惕脑干脑炎的发生。 BAEP检查对脑干损伤有较好的诊断价值。及时和规范治疗后大多数患儿的预后良好。     

听性脑干诱发电位Ⅴ波潜伏期耳间差值与新生儿高胆红素血症的相关性研究

目的 研究用短声（强度60 dBnHL）刺激患儿产生听性脑干诱发电位,探讨不同血清总胆红素（total serum bilirubin,TSB）水平患儿Ⅴ波潜伏期耳间差值（inter-aural latency difference,ILD）是否有差异性。方法 前瞻性选取2019年5月至2020年10月在浙江省玉环市人民医院新生儿科收治的高胆红素血症患儿。根据TSB水平分为重症组（n=50）、轻症组（n=50）;轻症组根据日龄分为日龄7~10 d亚组（n=20）、日龄11~14 d亚组（n=20）,分析ILD在不同TSB水平间的差异及其诊断价值。结果 重症组听阈异常比例、ILD异常比例均高于轻症组（P < 0.05）,重症组Ⅴ波ILD大于轻症组（P < 0.05）。轻症组日龄7~10 d亚组单耳Ⅴ波潜伏期长于日龄11~14 d亚组（P < 0.05）,而两亚组Ⅴ波ILD差异无统计学意义（P > 0.05）。受试者工作特征曲线分析显示,ILD对新生儿高胆红素血症导致的听力损伤有预测价值（P < 0.05）,曲线下面积为0.727,最佳截断值为0.365 ms（接近0.4 ms）,灵敏度为52.4%,特异度为90.9%。结论 新生儿血清胆红素浓度影响听性脑干诱发电位的Ⅴ波ILD,在重症高胆红素血症中尤其明显。ILD≥0.4 ms作为诊断新生儿高胆红素血症导致的听力损伤具有潜在价值。     

Time course of brainstem pathophysiology during first month in term infants after perinatal asphyxia,revealed by MLS BAER latencies and intervals

Dynamic changes in electrophysiology of brainstem auditory neurons during the first month after birth were studied in 51 term infants after perinatal asphyxia using maximum length sequence brainstem auditory evoked responses. The responses were recorded on d 1, 3, 5, 7, 10, 15, and 30 after birth. On d 1, wave III and V latencies and all interpeak intervals increased significantly at all repetition rates of clicks used (91-910/s), especially the higher rates (ANOVA, p < 0.05-0.0001). On d 3, all these latencies and intervals increased further and differed more significantly from the normal control subjects. Thereafter, the latencies and intervals decreased progressively. On d 7, wave V latency and all intervals still differed significantly from the control subjects. These dynamic changes were more significant at higher rates of clicks than at lower rates. On d 10 and 15, all intervals decreased significantly. On d 30, all wave latencies decreased to the values in the normal control subjects on the same day. The intervals also approached normal values, although the III-V and I-V intervals still increased slightly. These results indicate that hypoxic-ischemic brain damage persists during the first week, with a peak on d 3, and recovers progressively thereafter. By 1 mo, the damage has largely returned to normal. Maximum length sequence brainstem auditory evoked responses results correlated well with the stage of hypoxic-ischemic encephalopathy during the first week. The present study revealed a general time course of brainstem pathophysiology after asphyxia, although there were individual variations. Our findings can be used as a reference to monitor cerebral function and help judge the value of neuroprotective or therapeutic interventions. The first week, particularly the first 3 d, is a critical period of hypoxic-ischemic brain damage, and early intervention may prevent or reduce deterioration of the damage.     

Comparison of brainstem auditory evoked responses recorded at different presentation rates of clicks in term neonates after asphyxia

This study examined whether high presentation rates of clicks while recording brainstem auditory evoked responses (BAER) can improve the detection of central auditory impairment in asphyxiated neonates using the BAER. The BAER was analysed at different presentation rates of clicks within the first week after birth in 38 term neonates who suffered perinatal asphyxia. At the routinely used 21 s(-1) clicks all BAER wave latencies increased significantly (ANOVA, p < 0.05-0.01). After excluding five neonates who had a significantly elevated BAER threshold, only wave V latency increased slightly (p < 0.05). The interpeak intervals of I-V and III-V also increased slightly (both p < 0.05). Similar results were found at 51 s(-1) clicks. As the clicks were increased to 91 s(-1), the III-V interval increased more significantly (p < 0.01) and the III-V/I-III interval ratio also increased significantly (p < 0.01). In particular, wave V amplitude reduced more significantly than that in normal term controls (p < 0.01). Compared with values in the controls, wave V amplitude reduced by 4.5%, 12.2% and 24.7% at 21, 51 and 91 s(-1) clicks, respectively. Conclusion: Although a moderate increase in the rate (e.g. 51 s(-1)) while recording the BAER did not improve the detection of hypoxic-ischaemic auditory impairment, a significant increase (e.g. 91 s(-1)) did, which mainly indicates an abnormal reduction in wave V amplitude.     

高胆红素血症新生儿总胆红素/白蛋白比值与脑干听觉诱发电位的关系

目的 探讨总胆红素/白蛋白比值与脑干听觉诱发电位(BAEP)的相关性及其预测高胆红素血症新生儿听力损害的临床价值.方法 检测113例新生儿的总胆红素(TSB)、白蛋白水平,计算总胆红素/白蛋白比值(B/A),将B/A值≥ 3.0 × 10-3的83例新生儿作为观察组,并根据B/A值分4个亚组;另30例B/A ﹤ 3.0 × 10-3的新生儿作为对照组.检测所有新生儿的BAEP,分析TSB水平、B/A值与BAEP异常的相关性.结果 观察组各亚组间新生儿的BAEP异常率差异有统计学意义(P ＜ 0.01),随B/A值增大,BAEP异常率增高;观察组各亚组间新生儿BAEP的Ⅴ波潜伏期及Ⅰ-Ⅴ、Ⅲ-Ⅴ波间期的差异有统计学意义(P均＜ 0.05);TSB水平、B/A值的工作特征曲线(ROC)下面积(AUC)差异也有统计学意义(P ＜ 0.05);BAEP异常与B/A值密切相关(χ2 ＝ 13.489,P ＜ 0.05).结论 B/A值与BAEP异常相关性高,具有预测高胆红素血症新生儿听力损害的临床价值.     

脑干听觉诱发电位对结核性脑膜炎的预后评估价值

目的 探讨脑干听觉诱发电位(BAEP)对儿童结核性脑膜炎(TBM)预后的评估价值.方法 对2007年1月-2010年 8月本科初治的48例TBM患儿进行BAEP检测.男28例,女20例;年龄1～13岁.测量Ⅰ、Ⅲ 、Ⅴ波潜伏期和波幅,Ⅰ～Ⅲ、Ⅲ～Ⅴ、Ⅰ～Ⅴ波峰间期.BAEP结果分级采用Hall分级标准.TBM患儿入院当天行改良Glasgow评分.出院后随访3个月,比较不同 BAEP 级别TBM患儿的预后不良率;比较BAEP和Glasgow评分对TBM患儿预后评估的价值.结果 BAEP 1级18例中预后不良 1例,2级22例中预后不良6例,3级6例中预后不良4例,4级2例均预后不良;BAEP中1级、2级、3级和4级的预后不良率分别为5.6%、27.3%、66.7%和100.0%,差异有统计学意义(P<0.01).BAEP分级与不良预后发生率呈正相关(r=0.56,P<0.05).BAEP 对TBM患儿的预后评估:真阴性38例,假阴性2例,真阳性7例,假阳性1例;Glasgow评分对TBM患儿的预后评估:真阴性31例,假阴性5例,真阳性4例,假阳性8例;BAEP对TBM患儿预后评估的敏感性、特异性、准确率和错误率分别为77.8%、97.4%、93.6%和6.3%;Glasgow评分对TBM患儿预后评估的敏感性、特异性、准确率和错误率分别为44.4%、79.5%、72.9%和 27.1%,2种评估方法比较差异有统计学意义(Pa<0.05,0.01).结论 BAEP可反映TBM患儿的脑损伤程度,有助于评估预后;BAEP对TBM患儿的预后评估价值优于Glasgow评分.     

Early development of brainstem auditory evoked potentials in Down's syndrome

Early development of brainstem auditory pathway was studied in 14 children with Down's syndrome (age range from 1 month to 3 years). The brainstem auditory evoked potentials (BAEP) during infancy was characterized by elevated threshold and poorly differentiated wave I. All children within 2 years had elevated threshold in one or both ears, suggesting a high incidence of peripheral hearing deficits. Follow-up tests showed that as age increased up to 3 years the elevated threshold gradually decreased and the differentiation of wave I improved. The I-V interpeak interval was slightly shorter and the amplitude of wave V was smaller than the normal controls, which existed continuously during follow-up studies. Our findings suggest that the development of peripheral hearing is delayed, although persistent hearing deficits cannot be excluded, and the functioning and development of the brainstem auditory pathway may also be abnormal in Down's syndrome children.