Original articleReduced wave amplitudes of brainstem auditory response in high-risk babies born at 28-32Â week gestation

ObjectiveTo examine brainstem auditory electrophysiology in high-risk babies born at 28-32 week gestation by analysing the amplitudes of wave components in maximum length sequence brainstem auditory evoked response (MLS BAER).Methods94 preterm babies, ranging in gestation 28-32 weeks, with perinatal problems (high-risk) were recruited. The amplitudes of MLS BAER wave components were studied at term age (37-42 weeks postconceptional age).ResultsCompared with normal term controls, the amplitude in the high-risk preterm babies was significantly smaller at the highest click rate 910/s for wave I (p < 0.01), at all 91-910/s for wave III (all p < 0.01) and at 455 and 910/s (p < 0.05 and 0.01) for wave V. Compared with age-matched low-risk preterm controls, the amplitude was significantly smaller at 455 and 910/s for wave I (p < 0.05 and 0.05), 91-910/s for wave III (p < 0.05-0.001), and 227-910/s (p < 0.05 and 0.01) for wave V. No differences in the V/I and V/III amplitude ratios were found between the high-risk preterm babies and the controls.ConclusionsThe amplitudes of MLS BAER wave components, mainly more central components, were reduced in the high-risk preterm babies born at 28-32 week gestation. Electrophysiological activity of the brainstem auditory neuron in such babies is depressed, mainly attributed to or related to the associated perinatal problems.