Department of Audiology and Speech Pathology, Bauru Dental School, University of São Paulo, Brazil.
Department of Audiology and Speech Pathology, Federal University of Rio Grande do Norte, Natal, Brazil.
J Speech Lang Hear Res. 2018 Jul 13;61(7):1784-1793. doi: 10.1044/2018_JSLHR-H-16-0291.
The aims of the study were to examine the acoustic reflex screening and threshold in healthy neonates and those at risk of hearing loss and to determine the effect of birth weight and gestational age on acoustic stapedial reflex (ASR).
We assessed 18 healthy neonates (Group I) and 16 with at least 1 risk factor for hearing loss (Group II); all of them passed the transient evoked otoacoustic emission test that assessed neonatal hearing. The test battery included an acoustic reflex screening with activators of 0.5, 1, 2, and 4 kHz and broadband noise and an acoustic reflex threshold test with all of them, except for the broadband noise activator.
In the evaluated neonates, the main risk factors were the gestational age at birth and a low birth weight; hence, these were further analyzed. The lower the gestational age at birth and birth weight, the less likely that an acoustic reflex would be elicited by pure-tone activators. This effect was significant at the frequencies of 0.5, 1, and 2 kHz for gestational age at birth and at the frequencies of 1 and 2 kHz for birth weight. When the broadband noise stimulus was used, a response was elicited in all neonates in both groups. When the pure-tone stimulus was used, the Group II showed the highest acoustic reflex thresholds and the highest percentage of cases with an absent ASR. The ASR threshold varied from 50 to 100 dB HL in both groups. Group II presented higher mean ASR thresholds than Group I, this difference being significant at frequencies of 1, 2, and 4 kHz.
Birth weight and gestational age at birth were related to the elicitation of the acoustic reflex. Neonates with these risk factors for hearing impairment were less likely to exhibit the acoustic reflex and had higher thresholds.
本研究旨在探讨听力正常新生儿和有听力损失风险新生儿的声反射筛查和阈值，并确定出生体重和胎龄对镫骨声反射（ASR）的影响。
我们评估了 18 例健康新生儿（I 组）和 16 例至少有 1 项听力损失风险因素的新生儿（II 组）；所有新生儿均通过瞬态诱发耳声发射测试评估新生儿听力。测试包括 0.5、1、2 和 4 kHz 纯音激活的声反射筛查和宽带噪声声反射阈值测试，除宽带噪声激活器外，所有测试均进行。
在评估的新生儿中，主要的风险因素是出生时的胎龄和出生体重低；因此，进一步对这些因素进行了分析。出生时胎龄和出生体重越低，纯音激活器引出声反射的可能性越小。这种影响在出生时的胎龄为 0.5、1 和 2 kHz 以及出生体重为 1 和 2 kHz 的频率下具有统计学意义。当使用宽带噪声刺激时，两组中所有新生儿均产生反应。当使用纯音刺激时，II 组的声反射阈值最高，无 ASR 的病例比例最高。两组的 ASR 阈值在 50 至 100 dB HL 之间。与 I 组相比，II 组的平均 ASR 阈值较高，在 1、2 和 4 kHz 时差异具有统计学意义。
出生体重和胎龄与声反射的引出有关。有听力损伤风险因素的新生儿不太可能表现出声反射，并且阈值较高。
