| 11. |
- Reinfeldt, Sabine, 1978, et al.
(författare)
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Study of the Feasible Size of a Bone Conduction Implant Transducer in the Temporal Bone
- 2015
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Ingår i: Otology and Neurotology. - 1531-7129 .- 1537-4505. ; 36:4, s. 631-637
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Tidskriftsartikel (refereegranskat)abstract
- Hypothesis: The aim was to assess the temporal bone volume to determine the suitable size and position of a bone conduction implant (BCI) transducer. Background: A BCI transducer needs to be sufficiently small to fit in the mastoid portion of the temporal bone for a majority of patients. The anatomical geometry limits both the dimension of an implanted transducer and its positions in the temporal bone to provide a safe and simple surgery. Methods: Computed tomography (CT) scans of temporal bones from 22 subjects were virtually reconstructed. With an algorithm in MATLAB, the maximum transducer diameter as function of the maximum transducer depth in the temporal bone, and the most suitable position were calculated in all subjects. Results: An implanted transducer diameter of 16 mm inserted at a depth of 4 mm statistically fitted 95% of the subjects. If changing the transducer diameter to 12 mm, a depth of 6 mm would fit in 95% of the subjects. The most suitable position was found to be around 20 mm behind the ear canal. Conclusion: The present BCI transducer casing, used in ongoing clinical trials, was designed from the results in this study, demonstrating that the present BCI transducer casing (largest diameter [diagonal]: 15.5 mm, height: 6.4 mm) will statistically fit more than 95% of the subjects. Hence, the present BCI transducer is concluded to be sufficiently small to fit most normal-sized temporal bones and should be placed approximately 20 mm behind the ear canal.
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| 12. |
- Rigato, Cristina, 1989, et al.
(författare)
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Audiometric Comparison Between the First Patients With the Transcutaneous Bone Conduction Implant and Matched Percutaneous Bone Anchored Hearing Device Users
- 2016
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Ingår i: Otology & Neurotology. - : Ovid Technologies (Wolters Kluwer Health). - 1531-7129 .- 1537-4505. ; 37:9, s. 1381-1387
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Tidskriftsartikel (refereegranskat)abstract
- Hypothesis:The transcutaneous bone conduction implant (BCI) is compared with bone-anchored hearing aids (BAHAs) under the hypothesis that the BCI can give similar rehabilitation from an audiological as well as patient-related point of view.Background:Patients suffering from conductive and mixed hearing losses can often benefit more from rehabilitation using bone conduction devices (BCDs) rather than conventional air conduction devices. The most widely used BCD is the percutaneous BAHA, with a permanent skin-penetrating abutment. To overcome issues related to percutaneous BCDs, the trend today is to develop transcutaneous devices, with intact skin. The BCI is an active transcutaneous device currently in a clinical trial phase. A potential limitation of active transcutaneous devices is the loss of power in the induction link over the skin. To address this issue, countermeasures are taken in the design of the BCI, which is therefore expected to be as effective as percutaneous BCDs.Methods:An early observational study with a matched-pair design was performed to compare BCI and BAHA groups of patients over several audiometric measurements, including speech audiometry and warble tones thresholds with and without the device. Additionally, questionnaires were used to assess the general health condition, benefit, and satisfaction level of patients.Results:No statistically significant difference was detected in any of the audiological measurements. The outcome of patient-related measurements was slightly superior for BCI in all subscales.Conclusion:Results confirm the initial hypothesis of the study: the BCI seems to be capable of providing as good rehabilitation as percutaneous devices for indicated patients.
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| 13. |
- Roosli, Christof, et al.
(författare)
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Intracranial Pressure and Promontory Vibration With Soft Tissue Stimulation in Cadaveric Human Whole Heads
- 2016
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Ingår i: Otology and Neurotology. - : LIPPINCOTT WILLIAMS & WILKINS. - 1531-7129 .- 1537-4505. ; 37:9, s. E384-E390
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Tidskriftsartikel (refereegranskat)abstract
- Hypothesis:Intracranial pressure and skull vibrations are correlated and depend on the stimulation position and frequency.Background:A hearing sensation can be elicited by vibratory stimulation on the skin covered skull, or by stimulation on soft tissue such as the neck. It is not fully understood whether different stimulation sites induce the skull vibrations responsible for the perception or whether other transmission pathways are dominant. The aim of this study was to assess the correlation between intracranial pressure and skull vibration measured on the promontory for stimulation to different sites on the head.Methods:Measurements were performed on four human cadaver heads. A bone conduction hearing aid was held in place with a 5-Newton steel headband at four locations (mastoid, forehead, eye, and neck). While stimulating in the frequency range of 0.3 to 10kHz, acceleration of the cochlear promontory was measured with a Laser Doppler Vibrometer, and intracranial pressure at the center of the head with a hydrophone.Results:Promontory acceleration and intracranial pressure was measurable for all stimulation sites. The ratios were comparable between all stimulation sites for frequencies below 2kHz.Conclusion:These findings indicate that both promontory acceleration and intracranial pressure are involved for stimulation on the sites investigated. The transmission pathway of sound energy is comparable for the four stimulation sites.
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| 14. |
- Senn, Pascal, et al.
(författare)
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NANOCI-Nanotechnology Based Cochlear Implant With Gapless Interface to Auditory Neurons
- 2017
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Ingår i: Otology and Neurotology. - 1531-7129 .- 1537-4505. ; 38:8, s. E224-E231
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Tidskriftsartikel (refereegranskat)abstract
- Cochlear implants (CI) restore functional hearing in the majority of deaf patients. Despite the tremendous success of these devices, some limitations remain. The bottleneck for optimal electrical stimulation with CI is caused by the anatomical gap between the electrode array and the auditory neurons in the inner ear. As a consequence, current devices are limited through 1) low frequency resolution, hence suboptimal sound quality and 2), large stimulation currents, hence high energy consumption (responsible for significant battery costs and for impeding the development of fully implantable systems). A recently completed, multinational and interdisciplinary project called NANOCI aimed at overcoming current limitations by creating a gapless interface between auditory nerve fibers and the cochlear implant electrode array. This ambitious goal was achieved in vivo by neurotrophin-induced attraction of neurites through an intra-cochlear gel-nanomatrix onto a modified nanoCI electrode array located in the scala tympani of deafened guinea pigs. Functionally, the gapless interface led to lower stimulation thresholds and a larger dynamic range in vivo, and to reduced stimulation energy requirement (up to fivefold) in an in vitro model using auditory neurons cultured on multi-electrode arrays. In conclusion, the NANOCI project yielded proof of concept that a gapless interface between auditory neurons and cochlear implant electrode arrays is feasible. These findings may be of relevance for the development of future CI systems with better sound quality and performance and lower energy consumption. The present overview/review paper summarizes the NANOCI project history and highlights achievements of the individual work packages.
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| 15. |
- Smeds, H., et al.
(författare)
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X-linked Malformation and Cochlear Implantation
- 2017
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Ingår i: Otology and Neurotology. - : Ovid Technologies (Wolters Kluwer Health). - 1531-7129 .- 1537-4505. ; 38:1, s. 38-46
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Tidskriftsartikel (refereegranskat)abstract
- Objective: To evaluate if cochlear implantation is safe and constitutes an option for hearing rehabilitation of children with x-linked inner ear malformation. Study Design: Retrospective patient review in combination with a multidisciplinary follow-up. Patients: Ten children with severe-profound mixed hearing loss and radiological findings consistent with Incomplete Partition type 3 cochlear malformation received cochlear implants during the years 2007 to 2015. Nine of the children had a mutation affecting the gene POU3F4 on Xq21. Main Outcome Measures: Surgical events, intraoperative measures and electrical stimulation levels, hearing and spoken language abilities. Results: In all, 15 cochlear implantations were performed. In three cases the electrode was found to be in the internal auditory canal on intraoperative x-ray and repositioned successfully. One child had a postoperative rhinorrhea confirmed to be cerebrospinal fluid but this resolved on conservative treatment. No severe complications occurred. Postoperative electrical stimulation levels were higher in 9 of 10 children, as compared with typically reported average levels in patients with a normal cochlea. Eight patients developed spoken language to various degrees while two were still at precommunication level. However, speech recognition scores were lower than average pediatric cases. Conclusion: Cochlear implantation is a safe procedure for children with severe-profound mixed hearing loss related to POU3F4 mutation inner ear malformation. The children develop hearing and spoken language but outcome is below average for pediatric CI recipients.
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| 16. |
- den Besten, C. A., et al.
(författare)
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Stability, Survival, and Tolerability of an Auditory Osseointegrated Implant for Bone Conduction Hearing: Long-Term Follow-Up of a Randomized Controlled Trial
- 2016
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Ingår i: Otology & Neurotology. - : Ovid Technologies (Wolters Kluwer Health). - 1531-7129. ; 37:8, s. 1077-1083
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Tidskriftsartikel (refereegranskat)abstract
- Objective: To compare implant stability, survival, and soft tissue reactions for a novel (test) and previous generation (control) percutaneous auditory osseointegrated implant for bone conduction hearing at long-term follow-up of 5 years. Study Design: Single follow-up visit of a previously completed multicenter, randomized, controlled trial. Patients: Fifty-seven of the 77 participants of a completed randomized controlled trial on a new auditory osseointegrated implant underwent a single follow-up visit 5 years after implantation, which comprised implant stability measurements and collection of Holgers scores. Additionally, implant survival was recorded for all 77 patients from the original trial. Results: The test implant showed significantly higher implant stability quotient (ISQ) values compared with the control implant throughout the 5-year follow-up. Mean area under the curve of ISQ high from baseline to 5 years was 71.6 (standard deviation [SD] +/-2.0) and 66.7 (SD +/-3.4) for the test and control implant, respectively (p < 0.0001). For both implants, the mean ISQ value recorded at 5 years was higher compared with implantation (test group +2.03 [SD +/-2.55, within group p < 0.0001] and control group +2.25 [SD +/-4.95, within group p = 0.12]). No difference was noticed in increase from baseline between groups (p = 0.64). Furthermore, evaluation of soft tissue reactions continued to show superiority of the test implant. At the 5-year follow-up visit, one patient (2.5%) presented with a Holgers grade 2 in the test group, compared with four patients (23.5%) in the control group (p = 0.048); no patient presented with more severe soft tissue reactions. Excluding explantations, the survival rate was 95.8% for the test group and 95.0% for the control group. The corresponding rates including explantations were 93.9 and 90.0%. Conclusion: The test implant showed superiority in terms of higher mean ISQ values and less adverse soft tissue reactions, both at the single 5-year follow-up visit and during the complete follow-up. In addition, both implants showed an equally high implant survival.
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| 17. |
- Larsson, Anna, 1973, et al.
(författare)
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Implant Losses for the Bone-Anchored Hearing Devices Are More Frequent in Some Patients.
- 2015
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Ingår i: Otology & neurotology : official publication of the American Otological Society, American Neurotology Society [and] European Academy of Otology and Neurotology. - 1537-4505. ; 36:2, s. 336-340
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Tidskriftsartikel (refereegranskat)abstract
- Our knowledge of implant losses for bone-anchored hearing devices (BAHD) is still limited. This study examined the long-term survival rate, the reasons for implant loss, and the need for implant replacement in a large cohort with a long follow-up.
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| 18. |
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| 19. |
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| 20. |
- Sjögren, Julia, et al.
(författare)
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Steroids for Acute Vestibular Neuronitis-the Earlier the Treatment, the Better the Outcome?
- 2019
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Ingår i: Otology & Neurotology. - 1537-4505. ; 40:3, s. 372-374
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: To present findings that suggest steroid treatment within 24 hours of onset of vestibular neuronitis results in better restitution of vestibular function than treatment between 25 and 72 hours. PATIENTS: Thirty-three consecutive patients (17 men, 16 women, mean age 57 yr, range 17-85 yr) with acute vestibular neuronitis and treated with steroids within 72 hours after symptom onset. Patients were divided into two groups depending on if they were treated within the first 24 hours or not. INTERVENTIONS: Oral prednisolone 50 mg/d for 5 days with tapering of doses for the next 5 days, or combined with initial intravenous betamethasone 8 mg the first 1 to 2 days if the patient was nauseous. MAIN OUTCOME MEASURES: Proportion of patients with normal caloric test result (canal paresis value < 32%) at follow-up after 3 or 12 months. RESULTS: All 9 patients (100%) treated within 24 hours from onset of vestibular neuronitis had normal caloric test results at follow-up after 3 months, as compared with 14 of 24 (58%) of the patients treated between 25 and 72 hours (p < 0,05, Fisher's exact test). CONCLUSIONS: The timing of steroid treatment of vestibular neuronitis may be of importance for subsequent vestibular restitution, and hence, for both time to recovery and late symptoms according to the literature.
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