目的：探讨最大长度序列（maximum length sequences）脑干听觉诱发电位（以下简称MLS BAEP），对窒息新生儿早期检查判断其缺氧缺血性脑病（HIE）及程度的意义。方法：对26例正常新生儿和103例窒息新生儿于出生后3 d内分别行常规脑干听觉诱发电位（常规BAEP）和MLS BAEP检查。将103例窒息患儿，分组为无HIE组17例，轻度HIE组37例，中度HIE组31例，重度HIE组18例。所得检查波形定位分析后取I，III，V波潜伏期及振幅，I-III，III-V，I-V峰间期作为评价指标。结果：在常规BAEP和MLS BAEP中，V波潜伏期，I-III，III-V，I-V峰间期随HIE程度的加重逐渐延长的差异较明显，尤其在MLS BAEP中随声刺激速度的加快这种差异也越显著。各亚组与正常组两两比较中，轻度和/或中度HIE组的I-III，III-V峰间期在常规BAEP无差异，而在MLS BAEP中差别有统计学意义，并随声刺激速度增加统计学差异越显著。结论：MLS BAEP通过提高声刺激速度加大对听觉神经的负荷，为窒息缺氧后脑损伤的电生理检查提供了一个更敏感的方法，并对判断这种脑功能障碍有一定量化意义。

OBJECTIVE: To study the value of a new technique, maximum length sequences brainstem auditory evoked potential (MLS BAEP), in the assessment of the severity of brain damage following asphyxia in term neonates. METHODS: One hundred and three neonates with perinatal asphyxia and 26 normal term neonates were eligible for the study. Conventional and MLS BAEP examinations were performed within three days after birth. Of the 103 neonates with asphyxia, 17 did not suffer from HIE, 37 had mild HIE, 31 had moderate HIE, and 18 had severe HIE. The latencies and amplitudes of waves I, III and V, and the inter-peak intervals of I-III, III-V, and I-V were analyzed. RESULTS: The latencies of wave V and the inter-peak intervals of I-III, III-V and I-V prolonged gradually with the more severe HIE in both the MLS and the conventional BAEP (P<0.05 or 0.01). The differences among groups were more significant with the increasing repetition rate of click in the MLS BAEP. Compared with the normal controls, conventional BAEP did not show prolonged intervals of I-III and III-V in the mild HIE subgroup, and a prolonged inter-peak interval of III-V in the moderate HIE subgroup, while the MLS BAEP showed significantly prolonged inter-peak intervals of I-III and III-V in the three HIE subgroups and the differences were more and more significant as an increase in the repetition rate of click from 91 to 910 times/seconds. CONCLUSIONS: MLS BAEP is more sensitive and valuable than the conventional one in detecting hypoxic-ischemic brain damage following asphyxia by increasing the repetition rate of click. MLS BAEP provides a new measurement in quantity to assess the severity of HIE in neonates with perinatal asphyxia.