[Responsibility of mismatch negativity in neonates with hyperbilirubinemia].

OBJECTIVE:To explore the characteristics and application of mismatch negativity in hyperbilirubinemia neonates. METHOD:Eighty-six neonates with hyperbilirubinemia divided into low and high groups according to the bilirubin concentration of 342 micromol/L and 15 normal neonates for control group were measured with MMN and ABR. All subjects were enrolled and compared between the three groups,and followed up to 42 days old. RESULT:There were significantly different between the 3 groups of MMN latency(P < 0.01), and the average MMN latency was significantly shorter in the control group than in the hyperbilirubinemia groups(P<0. 05), and there are significantly but not closely positive correlation between the bilirubin concentration and the latency, the amplitudes of MMN remained similar between the 3 groups(P > 0.05). The wave V latencies and III-IV, I-V interwave intervals of the ABR were significantly different and prolonged during test in comparison with the control group (P < 0.05). But there were similar between the hyperbilirubinemia groups. The threshold of ABR in high group are significantly higher than the low group. During the follow up,the average MMN latency and the ABR wave latencies and interwave intervals except for interwave latency I-Ill , were significantly shorter. CONCLUSION:Hyperbilirubinemia are toxic to the hearing pathway and may affect the speech recognition of neonates. The higher of the bilirubin concentration,the higher risk of impairments to the auditory system, but most of the impairments are reversible. MMN,as an objective measure of the central auditory discrimination function and central auditory development are available. Compared with ABR, MMN is more sensitive in the evaluation of the central auditory function; If the application of MMN combined with ABR in the neonatal hyperbilirubinemia, a more comprehensive method in the auditory system evaluation can be obtained.