Establishment and rudimentary application of the method of recording auditory brainstem responses electrically stimulated via round-window niche in cochlear implants / 中华耳鼻咽喉头颈外科杂志

<p><b>OBJECTIVE</b>To establish the method of recording auditory brainstem responses electrically stimulated via round-window niche in cochlear implants.</p><p><b>METHODS</b>Self-made platinum iridium alloy as a spherical electrode stimulation electrode, modified cochlear implants connected to in vitro speech processor as a electro-stimulator and evoke potential instrument for Bio-logic Navigator Pro, 17 cochlear implant patients with various ages and of different causes, including auditory neuropathy (2 cases), ossified cochlea (1 case), inner ear malformation (5 cases), leukodystrophy (1 case), unknown and reason (8 cases) were investigated during cochlear implant surgery. Before cochlear implantation, stimulation electrode was placed in the round-window niche while charge balanced biphasic constant current was used as electrical stimulation via round window niche, and then electrically evoked auditory brainstem response was recorded.</p><p><b>RESULTS</b>Electrically evoked auditory brainstem response waveforms were clearly recorded in all 17 cases. The latencies of III and V waves were (2.12 +/- 0.18) ms and (4.18 +/- 0.19) ms respectively, with threshold as (220.0 +/- 16.04) CL. The waveforms of the 2 patients with auditory neuropathy, 5 patients with inner ear malformation, 1 patient with ossified cochlea and 1 patient with leukodystrophy were well differentiated.</p><p><b>CONCLUSIONS</b>Monitoring electrically evoked auditory brainstem response was an objective nerve electrophysiological testing method that accurately reflects function completeness of auditory pathway. It had important value for helping making the judgment whether patients could acquire auditory response after cochlear implantation. This method was safe and gave high emission of auditory response, therefore should be spread widely.</p>

Auditory pre-attentive processing of Chinese tones / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Chinese tones are considered important in Chinese discrimination. However, the relevant reports on auditory central mechanisms concerning Chinese tones are limited. In this study, mismatch negativity (MMN), one of the event related potentials (ERP), was used to investigate pre-attentive processing of Chinese tones, and the differences between the function of oddball MMN and that of control MMN are discussed.</p><p><b>METHODS</b>Ten subjects (six men and four women) with normal hearing participated in the study. A sequence was presented to these subjects through a loudspeaker, the sequence included four blocks, a control block and three oddball blocks. The control block was made up of five components (one pure tone and four Chinese tones) with equiprobability. The oddball blocks were made up of two components, one was a standard stimulus (tone 1) and the other was a deviant stimulus (tone 2 or tone 3 or tone 4). Electroencephalogram (EEG) data were recorded when the sequence was presented and MMNs were obtained from the analysis of the EEG data.</p><p><b>RESULTS</b>Two kinds of MMNs were obtained, oddball MMN and control MMN. Oddball MMN was obtained by subtracting the ERP elicited by standard stimulation (tone 1) from that elicited by deviant stimulation (tone 2 or tone 3 or tone 4) in the oddball block; control MMN was obtained by subtracting the ERP elicited by the tone in control block, which was the same tone as the deviant stimulation in the oddball block, from the ERP elicited by deviant stimulation (tone 2 or tone 3 or tone 4) in the oddball block. There were two negative waves in oddball MMN, one appeared around 150 ms (oddball MMN 1), the other around 300 ms (oddball MMN 2). Only one negative wave appeared around 300 ms in control MMN, which was corresponding to the oddball MMN 2. We performed the statistical analyses in each paradigm for latencies and amplitudes for oddball MMN 2 in discriminating the three Chinese tones and reported no significant differences. But the latencies and amplitudes for control MMN in discriminating the three tones all were significantly different.</p><p><b>CONCLUSIONS</b>There are evident waveforms for oddball and control MMN obtained in normal hearing persons, indicating that the change of Chinese tones could be detected in the pre-attentive stage. Because control MMN can eliminate reflects for physical characteristics of sound, it is the genuine memory-based pre-attentive processing. Since control MMN can reflect the differences of Chinese tones processing better than oddball MMN, it is more sensitive in evaluating pre-attentive processing in Chinese tones discrimination.</p>

Local response caused by implant after cochlear implantation / 中华耳鼻咽喉头颈外科杂志

<p><b>OBJECTIVE</b>To approach the incidence rate, symptoms, etiologies, correlating reasons, consequences and treatments of local responses caused by implant after cochlear implantation and to provide reference for the future works.</p><p><b>METHODS</b>From 1995 to 2007 there were 997 cases adopted cochlear implantation in Peding Union Medical College Hospital. Ten cases experienced local responses were analyzed retrospectively.</p><p><b>RESULTS</b>The incidence of local response was 1.003%. There were 6 males and 4 females. The ages were between 13 months to 8 years old. The average age was 34 months. The devices mainly were made by Cochlear and Med-EL companies. The mainly symptoms and signs were local swellings, complaint of pruritus after ear, decrease of sound legibility and so on. Onset frequencies of this disease was 1 to 8 times. The bacterium cultured of displacing liquids was negative. But the IgE was detected in 2 cases. Results showed the patients were midrange status of hypersensitivity. Positive conservative treatments must be done including antibiotics, antihistamines, necessarily using immunotherapy.</p><p><b>CONCLUSIONS</b>Besides local infection of bacteria, the allergy caused by silicone of implant coupled be a reason. Although the diagnose of this disease was difficult, but the screening of source of hypersensitivity was necessary before operation. It was recurrent attacks and maybe liable by kindred patients. Onset age was more below 4 years old. The patch test should be done again when the symptoms were occurrence after operation. If severe secondary infection was occurred and the states could not be well controlled the devices in the body must be explanted immediately. When the conditions were stable reimplantation could be experienced by non-sensibilisinogen devices.</p>

Cochlear implantation in patients with otitis media-related diseases / 中华耳鼻咽喉头颈外科杂志

<p><b>OBJECTIVE</b>To evaluate the indications, surgical techniques and complications of cochlear implantation in patients with otitis media-related diseases.</p><p><b>METHODS</b>Retrospective study of the data collected from patients receiving cochlear implantation. Totally 866 cases of cochlear implantation were performed in Peking Union Medical College Hospital from May 1995 to February 2006. Among which, 41 patients with otitis media-related diseases were grouped into 5 types: chronic secretory otitis media (13 cases), silent (subclinical) otitis media (18 cases), dry eardrum perforation (1 case), bilateral cholesteatoma of middle ear (2 cases) and middle ear granuloma (7 cases). Seven cases were accompanied with deformities of middle ear and (or) inner ear. Pedicled aponeurosis of occipitofrontalis muscle was transplanted to cover and protect the inserted electrodes and facial nerve in a patient with bilateral cholesteatoma after radical mastoidectomy.</p><p><b>RESULTS</b>All the 41 patients with otitis media-related diseases were successfully implanted in one stage or staged operations and followed up uneventfully for 5 months to 6 years and 11 months. All implant devices had worked normally and all patients had performed well.</p><p><b>CONCLUSIONS</b>Patients with chronic secretory otitis media, silent (subclinical) otitis media, middle ear granuloma or dry ear-drum perforation could be operated in one stage or staged procedures safely and effectively. Patients with bilateral cholesteatoma could be implanted after radical removal of related lesions. Pedicled aponeurosis of occipitofrontalis muscle could be transplanted in cases of mastoid bowl to cover and protect the inserted electrodes and the exposed facial nerve and with easy access to observe the mastoid cavity. Active suppurative otitis media was contraindicated for cochlear implantation. Long-term following-up was essential for better evaluation of the outcomes of cochlear implantation in patients with otitis media-related diseases.</p>

Voice analysis in pre-lingual cochlear implant adults / 中华耳鼻咽喉头颈外科杂志

<p><b>OBJECTIVE</b>To observe voice characteristic of pre-lingual cochlear implant adults for cochlear implantation and phoniatrics.</p><p><b>METHODS</b>3s-sustained voice of vowel [ a: ] of 28 pre-lingual cochlear implant adults, 18 pre-lingual deafness adults and 10 adults with normal hearing were analyzed. Specifically, the Voice analyses include fundamental frequency, first formant, second formant, frequency perturbation quotient (FPQ), amplitude perturbation quotient (APQ) and harmonic noise ratio (HNR). The outcomes of 3 groups were compared.</p><p><b>RESULTS</b>The fundamental frequency was lower in cochlear implant group [(175.42+/-25. 31) Hz] than that in deafness group [(210.84+/-54.300) Hz] (P = 0.02). The position of formant of cochlear implant group [F2 = (1264. 64 +/- 152.19) Hz] was more access to normal than that of normal hearing group[ F2 = (1422.44 +/- 232. 37) Hz, P = 0. 02]. FPQ of cochlear implant group (2.09 +/- 1.15) was more access to normal than that of deafness group (5.32+/-4.29, P=0.006). The voice of cochlear implanted and deafness adults were much more different individually.</p><p><b>CONCLUSIONS</b>In the aspect of acoustic characteristic of voice, pre-lingual cochlear implant adults could benefit cochlear implantation finitely. As speech perception of pre-lingual cochlear implant adults was far worse than that of children and post-lingual cochlear implant adults, the general outcome of pre-lingual cochlear implant adults was very limited. Cochlear implant of those candidate should be cautious.</p>