Technology for an advanced cochlear nucleus auditory prosthesis

先进的耳蜗核听觉假体技术

• 批准号: 7652422
• 负责人: Douglas Buchanan McCreery
• 金额: $ 38.52万
• 依托单位: HUNTINGTON MEDICAL RESEARCH INSTITUTES
• 依托单位国家: 美国
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-08-01 至 2012-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7652422
• 关键词: Acoustic Nerve; Acoustics; Address; Advanced Development; Affect; Animal Model; Animals; Auditory; Auditory Brain Stem Implants; Bilateral; Boron; Brain Stem; Cells; Charge; Chronic; Clinical; Cochlear Implants; Cochlear nucleus; Data; Detection; Developed Countries; Developing Countries; Development; Devices; Electric Stimulation; Electrodes; Equilibrium; Etiology; Excision; Exhibits; Family Felidae; Felis catus; Fracture; Hearing; Human; Hybrids; Implant; Inferior; Inferior Colliculus; Ions; Length; Live Birth; Location; Mechanics; Methods; Michigan; Microelectrodes; Modeling; Nerve; Neurofibromatosis 2; Neuroglia; Operative Surgical Procedures; Outcome Measure; Patients; Performance; Persons; Positioning Attribute; Prevalence; Probability; Prostheses and Implants; Prosthesis; Protocols documentation; Psychoacoustics; Pulse Rates; Reference Standards; Relative (related person); Silicon; Site; Specificity; Speech; Speech Perception; Spinal Cord; Staging; Stimulus; Surface; Surgeon; System; Technology; Thick; Time; Tissues; Vertebral column; Width; analog; bilateral vestibular Schwannoma; data acquisition; deafness; design; design and construction; experience; implantable device; implantation; improved; microstimulation; minimal risk; public health relevance; sound; speech recognition; tumor

DESCRIPTION (provided by applicant): We propose to develop technology that will better convey both the spectral and the temporal features of sound to persons with cochlear nucleus auditory prostheses. An auditory prosthesis at the level of the cochlear nucleus ("Auditory brainstem implant, ABI") can restore useful hearing to persons who lack functional auditory nerves, but their speech perception is much poorer than that of most users of cochlear implants, and is especially poor for persons afflicted with Type 2 Neurofibromatosis (NF2), the most prevalent etiology for bilateral loss of the 8th nerves. The NF2 patients also exhibit high modulation detection threshold which is the only psychoacoustic variable that has been found to distinguish the NF2 users of the ABIs from those whose deafness is of other etiologies. The available data suggests that all users of ABIs, including those with NF2, would benefit from improved modulation detection. Most ABIs utilize an array of macroelectrodes on the surface of the brainstem, and this array allows some, but limited access to the tonotopic organization of the cochlear nucleus. In animal studies, penetrating microelectrodes are better able to convey the spectral information of sound, and NF2 patients whose auditory brainstem implants includes arrays of surface and penetrating electrodes derive benefit from the hybrid array. However, our experience with the existing penetrating array has revealed several issues that we will address in the proposed studies. We will design an array of 96 microstimulating electrode sites on 24 multisite silicon substrate shanks microelectrodes, that will insure placement of at least 16 microstimulating sites within the human ventral cochlear nucleus, even with the known uncertainly as to where to position the array after removal of the 8th nerve tumor. The probes comprising this array will be fabricated by deep reactive ion etching (DRIE) photolithography, which yields probe shanks that are sufficiently durable to penetrate the glia limitans overlying the human cochlear nucleus. We will verify the mechanical durability of the array by repeated insertions into cat spinal cords. Arrays of DRIE probes will be implanted chronically into cats' cochlear nucleus to evaluate possible tissue damage during implantation of the mechanically robust DRIE probes. The standard of comparison will be Michigan-style probes that are much thinner than the DRIE probes. Also in a cat model, we will determine if and how modulation detection by Type 1 multipolar cells of the ventral cochlear nucleus can be enhanced, relative to that with a 250 Hz charge-balanced pulsatile stimulus used in the present clinical ABI systems. We will evaluate the merits of a higher stimulus pulse rate (500 and 1000 pps) and also of analog electrical stimulation. To support the activities described above, we will develop a 64-site, 4-shank recording array suitable for chronic implantation into the cats' inferior colliculus. PUBLIC HEALTH RELEVANCE: An auditory prosthesis implanted at the level of the cochlear nucleus (an "Auditory brainstem implant, ABI") can restore useful hearing to persons who lack functional auditory nerves, but their speech perception and recognition of environmental sounds is much poorer than that of most users of cochlear implants, and is particularly poor for persons afflicted with Type 2 Neurofibromatosis (NF2), the most prevalent etiology for bilateral loss of the auditory nerves. Typically, the nerves are destroyed during surgical resection of each of the bilateral vestibular schwannomas that are typical of this condition. The ABIs now in use do not efficiently convey to the users the temporal modulation of sound and persons with NF2 fare particularly poorly in this respect. In an animal model, we will compare several protocols for encoding sound into the electrical stimulation that is delivered to the stimulating electrodes. Our objective is to develop an improved method of conveying the temporal features of sound to ABI users. Most ABIs utilize an array of macroelectrodes on the surface of the brainstem that allows some, but limited access to the tonotopic organization of the cochlear nucleus. In animal studies, penetrating microelectrodes are better able to convey the spectral information of sound and NF2 patients whose auditory brainstem implants includes an array of surface electrodes and an array of penetrating electrodes derive benefit from the hybrid array. Also, the penetrating electrodes have proved useful in those instances when the patient does not receive auditory percepts from the surface electrodes. However, our experience with the existing version of the penetrating array has revealed a number of issues that we will address in the proposed studies. In view of the prevalence of NF2 relative to that of other causes of bilateral loss of the auditory nerves, it is most unfortunate that persons with NF2 have not obtained as much benefit from their auditory brainstem implants as have patients whose deafness is of other etiologies. However, the prevalence of NF2 is approximately 1 in 40,000 live births with a high probability of bilateral acoustic tumors, and so while the condition fortunately is quite rare, in developed countries alone, there are many thousands of persons who can benefit from these devices, and with minimal risk and discomfort in addition to those related to the surgical removal of the tumors, since the devices are implanted into the cochlear nucleus during the same surgical procedure in which the tumor is surgically removed. Thus there is a need for improvements to the implants themselves and for methods of encoding sound into electrical stimulus that are optimized for an auditory prosthesis implanted in the cochlear nucleus.

描述（由申请人提供）：我们建议开发技术，以更好地将声音的光谱和时间特征传达给具有耳蜗核听觉假体的人。 An auditory prosthesis at the level of the cochlear nucleus ("Auditory brainstem implant, ABI") can restore useful hearing to persons who lack functional auditory nerves, but their speech perception is much poorer than that of most users of cochlear implants, and is especially poor for persons afflicted with Type 2 Neurofibromatosis (NF2), the most prevalent etiology for bilateral loss of the 8th nerves. NF2患者还表现出高调制检测阈值，这是唯一发现ABI的NF2使用者与其他病因的精神声音变量。可用的数据表明，包括NF2的所有用户（包括NF2的用户）将受益于改进的调制检测。大多数ABI都在脑干表面使用了一系列大型电极，并且该阵列允许一些但有限的访问人工耳蜗核的吨位组织。在动物研究中，穿透微电极能够更好地传达声音的光谱信息，而听觉脑干植入物的NF2患者包括表面和穿透电极的阵列，从而从混合阵列中获得了好处。但是，我们在现有的穿透阵列的经验揭示了我们将在拟议的研究中解决的几个问题。我们将在24个多站点硅底物柄微电极上设计一个96个微刺激电极位点的阵列，这些阵列将确保将至少16个微刺激位点放置在人类腹侧耳蜗核中，即使在已知的不确定的位置，可以在8th nth Nerve nerve tumor thever tumor thever tumoter阵列后的位置不确定地定位。包含该阵列的探针将通过深部反应离子蚀刻（DRIE）光刻来制造，该探针产生的探针柄足够耐用，可以穿透覆盖着人类耳蜗核的Glia Limitans。我们将通过重复插入猫脊髓来验证阵列的机械耐用性。 DRIE探针阵列将长期植入猫的耳蜗核，以评估机械强化的DRIE探针植入期间可能的组织损伤。比较标准将是密歇根州风格的探针，它们比DRIE探针薄得多。同样在CAT模型中，我们将确定是否可以通过在本临床ABI系统中使用的250 Hz电荷平衡的脉冲平衡刺激来增强腹侧耳蜗核的1型多极细胞的调节检测。我们将评估较高的刺激脉搏率（500和1000 pps）以及模拟电刺激的优点。为了支持上述活动，我们将开发一个64个位点的4股记录阵列，适合于慢性植入猫的下丘。公共卫生相关性：在人工耳蜗核的水平上植入的听觉假体（“听觉脑干植入物，ABI”）可以恢复缺乏功能性听觉神经的人的有用听力，但他们对环境声音的言语感知和对环境声音的认识却比大多数人的神经植入物中的大多数人都差，而对于2型Neurfibrent的人来说，尤其是2型Neuroftibr，而不是型号。用于双边听觉神经的丧失。通常，在每种双侧前庭schwannomas的手术切除过程中，神经被破坏。现在使用的ABI并不能有效地向用户传达NF2的声音和人员的时间调制，而NF2的票价在这方面尤为差。在动物模型中，我们将比较几种将声音编码为电极传递到刺激电极的方案。我们的目标是开发一种改进的方法，将声音的时间特征传达给ABI用户。大多数ABI都利用脑干表面上的一系列大型电极，这使得一些但有限的访问对耳蜗核的构成组织的访问有限。在动物研究中，穿透微电极能够更好地传达声音和NF2患者的光谱信息，其听觉脑干植入物包括一系列表面电极和一系列穿透电极从混合阵列中获得益处。同样，在患者未从表面电极中接收听觉感知的那些情况下，穿透电极也很有用。但是，我们在现有版本的穿透性阵列的经验揭示了我们将在拟议的研究中解决的许多问题。鉴于NF2相对于听觉神经双侧丧失的其他原因的普遍性，最不幸的是，NF2患者没有从听觉脑干植入物中获得那么多的受益。 However, the prevalence of NF2 is approximately 1 in 40,000 live births with a high probability of bilateral acoustic tumors, and so while the condition fortunately is quite rare, in developed countries alone, there are many thousands of persons who can benefit from these devices, and with minimal risk and discomfort in addition to those related to the surgical removal of the tumors, since the devices are implanted into the cochlear nucleus during the same surgical手术切除肿瘤的过程。因此，需要改进植入物本身以及将声音编码为电刺激的方法，这些刺激被优化，该刺激是针对植入人耳蜗核的听觉假体进行了优化的。