Auditory Midbrain Implant Study
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|ClinicalTrials.gov Identifier: NCT02984202|
Recruitment Status : Recruiting
First Posted : December 6, 2016
Last Update Posted : February 22, 2019
|Condition or disease||Intervention/treatment||Phase|
|Deafness; Perception||Device: auditory midbrain implant (AMI)||Not Applicable|
Cochlear implants are used in the cochlea (part of the inner ear) where they send electrical signals for activation of the auditory nerve to restore hearing to deaf patients. For patients without a functioning auditory nerve, there is an auditory brainstem implant (ABI), which is placed on the surface of the brainstem in a more central location to restore hearing. Unfortunately, the hearing performance of the ABI is typically lower than the performance of the cochlear implant. There are several reasons for the lower success of the ABI. Due to the tumor and/or tumor removal process for the NF2 condition, there is potential damage caused at the brainstem level that has been linked to the poorer performance. The anatomical changes caused by the tumor also make it difficult to properly visualize and place the ABI surface array into the correct location. In addition, if there is a large tumor that needs to or has been removed, then there can be a large cavity in the brainstem space with the possibility that the ABI surface array can move from its initial location over time.
Therefore, for the past 16 years, a new implant has been developed in an international collaboration that presents electrical stimuli into a midbrain region, the inferior colliculus. This new implant is called the auditory midbrain implant (AMI). The current version consists of two shanks with with 11 electrode contacts linearly spaced along each shank. The two shanks are inserted into the inferior colliculus to align the electrodes along different pitch layers to be able to stimulate them individually with varying temporal pulse patterns.
In the period from 2006 to 2010, a former version of the current AMI was implanted and evaluated in five NF2 deaf patients for hearing restoration. This first AMI implant consisted of only one shank in contrast with the current two-shank array. Encouragingly, the clinical trial at that time showed that the AMI was safe for all five patients. All patients achieved improvements in their hearing capacity, especially in the form of environmental sound awareness and lip-reading enhancement. One patient additionally attained good speech perception that is within the upper range of ABI NF2 patients. However, this speech perception is not yet at the level that can be attained in cochlear implant patients.
Based on these experiences and additional studies in animals, we have developed the second version of the AMI that consists of two shanks that will be implanted into the inferior colliculus and is expected to provide significant improvements in hearing performance compared to the previous AMI by stimulating more effectively across the three-dimensional inferior colliculus.
The purpose of this clinical trial is to evaluate the safety, reliability, and performance of the new two-shank AMI in deaf NF2 patients. The ability to consistency place the AMI array into the inferior colliculus will also be evaluated.
|Study Type :||Interventional (Clinical Trial)|
|Estimated Enrollment :||5 participants|
|Intervention Model:||Single Group Assignment|
|Masking:||None (Open Label)|
|Official Title:||Phase I Safety Study for a New Two-Shank Auditory Midbrain Implant (AMI)|
|Actual Study Start Date :||October 2016|
|Estimated Primary Completion Date :||January 2021|
|Estimated Study Completion Date :||February 2021|
Patients will be implanted with the AMI and evaluated for safety and efficacy over a 2-year period. The placement of the AMI array into the inferior colliculus will also be evaluated.
Device: auditory midbrain implant (AMI)
- Collection of serious adverse events of AMI [ Time Frame: 24 months ]Collection of investigational device related serious adverse events during the evaluation period.
- Position of AMI array in midbrain [ Time Frame: 24 months ]Evaluation of the final position of the two shanks of the AMI array in the inferior colliculus which includes angles and insertion locations of each shank relative to specific anatomical landmarks. The frequency/pitch ordering of the sites along each shank will also be measured which provides how many electrode sites are correctly positioned into the inferior colliculus and thus the depth location of each shank relative to the surface of the midbrain. All of these measurements provide the final position of the AMI array in the midbrain.
- Speech perception performance of AMI [ Time Frame: 24 months ]Relative difference of the speech perception score between current ABI recipients with NF2 (collected data from the same clinical site) and AMI recipients with NF2 at the two-year post-operative evaluation visit.
To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT02984202
|Contact: Dyballa Karl-Heinz, PhD||Dyballa.Karl-Heinz@mh-hannover.de|
|Contact: Kludt Eugen, PhD||Kludt.Eugen@mh-hannover.de|