Department of Otolaryngology-Head and Neck Surgery, Tohoku University Graduate School of Medicine, 1-1 Seiryo-machi, Aoba-ku, Sendai 980-8574, Japan.
Clin Neurophysiol. 2012 May;123(5):985-92. doi: 10.1016/j.clinph.2011.10.044. Epub 2011 Nov 26.
To examine whether auditory evoked fields (AEFs) can be used to objectively evaluate hearing in patients with absent auditory brainstem responses (ABRs) due to auditory neuropathy.
Subjects were 3 patients with auditory neuropathy, 1 male aged 29 years and 2 females aged 18 and 27 years, with absence of click evoked ABRs for bilateral ear stimuli at a level of 105 dB nHL. All patients also had optic atrophy. AEFs were measured with a helmet-shaped magnetoencephalography system for 2.0 kHz tone bursts of 60 ms duration to the unilateral ear.
Bihemispherical AEF responses were clearly recorded in all three patients for either left or right ear stimulus. Although the latencies of N100m were severely prolonged and amplitudes were considerably decreased compared to the normal range of N100m responses in our facilities, N100m latency of AEF was shorter in the contralateral hemisphere to the stimulated ear, as usually found in normal subjects, despite the abnormal delay in N100m latency in all conditions.
Presence and abnormality of auditory cortical responses can be evaluated by AEFs in patients with auditory neuropathy even under null responses in ABRs.
AEFs are useful to evaluate residual hearing in patients with auditory neuropathy.
探讨听觉诱发电场（AEF）能否用于客观评估因听神经病而导致听性脑干反应（ABR）缺失的患者的听力。
研究对象为 3 例听神经病患者，其中男性 29 岁，女性 18 岁和 27 岁，双侧耳刺激强度为 105dB nHL 时，均缺失 click 诱发 ABR。所有患者均伴有视神经萎缩。采用头盔式脑磁图系统测量 2.0kHz 持续 60ms 的声刺激的 AEF。
3 例患者的左、右耳刺激均清晰记录到双侧半球 AEF 反应。尽管与本单位正常 N100m 反应相比，N100m 潜伏期显著延长，振幅明显降低，但与正常受试者相同，对侧半球的 N100m 潜伏期较受刺激耳的潜伏期短，尽管在所有条件下 N100m 潜伏期均存在异常延迟。
即使在 ABR 无反应的情况下，AEF 也可用于评估听神经病患者的听觉皮质反应的存在和异常。
AEF 可用于评估听神经病患者的残余听力。
