Laboratory of Rehabilitative Auditory Science, Tohoku University Graduate School of Biomedical Engineering, 1-1 Seiryo-machi, Aoba-ku, Sendai 980-8574, Japan; Department of Audiology, Tohoku University Graduate School of Medicine, 1-1 Seiryo-machi, Aoba-ku, Sendai 980-8574, Japan; Department of Otolaryngology-Head and Neck Surgery, Tohoku University Graduate School of Medicine, 1-1 Seiryo-machi, Aoba-ku, Sendai 980-8574, Japan.
Department of Functional Brain Imaging, Institute of Development, Aging and Cancer, Tohoku University, 4-1 Seiryo-cho, Aoba-ku, Sendai 980-8575, Japan; MEG Laboratory, Kohnan Hospital, 4-20-1 Nagamachi-minami, Taihaku-ku, Sendai 982-8523, Japan.
Clin Neurophysiol. 2014 Jan;125(1):148-53. doi: 10.1016/j.clinph.2013.06.184. Epub 2013 Jul 26.
To compare the detectability of the different auditory evoked responses in patients with retrocochlear lesion.
The 40-Hz auditory steady state response (ASSR) and the N1m auditory cortical response were examined by magnetoencephalography in 4 patients with vestibular schwannoma, in whom the auditory brainstem response (ABR) was absent.
Apparent N1m responses were observed despite total absence of the ABR or absence except for small wave I in all patients, although the latency of N1m was delayed in most patients. On the other hand, clear ASSFs could be observed only in one patient. Very small 40-Hz ASSFs could be detected in 2 patients (amplitude less than 1fT), but no apparent ASSFs were observed in one patient, in whom maximum speech intelligibility was extremely low and the latency of N1m was most prolonged.
The N1m response and 40-Hz ASSR could be detected in patients with absent ABR, but the N1m response appeared to be more detectable than the 40-Hz ASSR.
Combined assessment with several different evoked responses may be useful to evaluate the disease conditions of patients with retrocochlear lesions.
比较不同听觉诱发电位在迷路后病变患者中的可检测性。
对 4 例前庭神经鞘瘤患者进行了 40Hz 听觉稳态反应（ASSR）和 N1m 听觉皮质反应的磁共振脑磁图检查，这些患者的听觉脑干反应（ABR）缺失。
尽管所有患者的 ABR 完全缺失或除了小的波 I 外均缺失，但仍观察到明显的 N1m 反应，尽管大多数患者的 N1m 潜伏期延迟。另一方面，仅在 1 例患者中可观察到清晰的 ASSFs。在 2 例患者中可以检测到非常小的 40Hz ASSFs（幅度小于 1fT），但在 1 例患者中未观察到明显的 ASSFs，该患者的最大言语可懂度极低，且 N1m 潜伏期最长。
在 ABR 缺失的患者中可以检测到 N1m 反应和 40Hz ASSR，但 N1m 反应似乎比 40Hz ASSR 更易检测。
联合评估几种不同的诱发电位可能有助于评估迷路后病变患者的病情。
