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Objective: For cochlear implant recipients, undergoing MRI scans is associated with safety risks and potential side effects. Even following safety guidelines, potential complications(e.g., pain, magnet dislocation, image artifacts) are possible during 1.5 TeslaMRI scans. The stronger static magnetic field of a 3.0 T scanner is associated with further risks of complication, including implant demagnetization. These complications led to the recent development of rotatable internal receiver magnets with a diametrical magnetization. The aim of this study was to evaluate the potential occurrence of pain during 3.0 Tesla MRI scans for cochlear implant recipients with a rotatable, diametrically magnetized implant magnet. Method: In the prospective case study an 3T MRI scan was performed on 25 implantees and the degree of pain was evaluated by a visual analog scale. Results: In all patients, all MRI scans were performed without any pain, Demagnetization was clinically not observed. Conclusion:3.0 T MRI scanning can be performed on cochlear implant recipients with a rotatable diametrically magnetized internal magnet without risk of the most frequent cochlear-implant-related MRI complication: pain. This finding enables the expansion of MRI scanning indications up to 3.0 T without complication. Limitations in terms of MRI artifact still persist. [ABSTRACT FROM AUTHOR]

Objective: MRI observation is part of the regular tumor follow up after the resection of vestibular or intralabyrinthine schwannoma. Since cochlear implantation after intralabyrinthine tumor resection is a central part of the audiological rehabilitation MRI behavior of CI systems needs to be considered. With recent developments in MRI artifact position and pain prevention it was the aim of the present study to evaluate MRI observations after tumor resection and CI surgery. Methods: We evaluated 5 patients with a T1 KM sequence MRI observation after intralabyrinthine tumor resection and cochlear implantation. Timespan between tumor resection/ cochlear implantation and MRI scan was between 1 day and 8 years. Results: In all cases the MRI- observation allowed a visual assessment of the intralabyrinthine tumor region. Conclusion: MRI follow up after intralabyrinthine schwannoma resection and cochlear implantation needs to be considered before cochlear implantation to allow a visual assessment afterwards. [ABSTRACT FROM AUTHOR]

Objective: A well-known and frequently reported complication after cochlear implantation is the appearance of postoperative vertigo symptoms. Perilymphatic fistula (PLF) is a known cause for hearing loss and vertigo. Cochlin-tomoprotein (CTP) is a cochlear specific protein acting as a marker for PLF. Aim of the present study was to observe, if the postoperatively new occurence of vertigo is caused by a perilymphatic fistula evidenced by CTP marker . Methods: In a prospective analysis 12 cochlear implant patients with the postoperatively new occurence of vertigo underwent a transtympanally revison/resealing surgery. In all patients middle ear fluid was captured and analysed for CTP. Results: In 5 out of 12 patients a positive CTP result was found indicating a PLF. Positive PLF finding did not correlate with the intraoperative visual assumption of a leak. The procedure solves in most of the cases the vertigo problem. Conclusion: Our present finding demonstrates that objectively an insufficent sealing causing perilymphatic fistula occurs frequently in cases of newly postoperative vertigo after cochlea implantation. [ABSTRACT FROM AUTHOR]

Objective: Conventional treatments for single sided deaf subjects (SSD) are very limited. If treated at all, acoustic signals are only picked up from the deaf side and routed to the hearing side either as an electrical signal (CROS) or through bone conduction (BAHA). Both methods use for the transmission of auditory signals only the contra lateral hearing cochlea and do not utilize the peripheral auditory pathways on both sides. However, through electrical stimulation via a cochlear implant the deaf side can be activated. The aim of our present study was to demonstrate that in such a case speech reception in noise and localization can be improved. Study design: Nine adult participants with short-term unilateral deafness (<5 yr) participated. All had sudden onset of severe-to-profound hearing loss in 1 ear, which then received a CI, and normal or near normal hearing in the other ear. Speech recognition in quiet and noise with an adaptive sentence test was tested after 3 months, 6 months and 12 months. Three binaural effects were calculated: summation effect (S0N0), squelch effect (S0NCI) and combined head shadow effect (SCIN0). For localization, a 7 loudspeaker setup (± 90°, 30° distance) was used. Discrimination was tested preoperatively (normal hearing (NH) ear alone) and after 12 months bilaterally (CI and NH). Results: One subject quit the study after 3 months due to subjectively limited benefit. All other participants had open-set speech recognition and excellent audibility with the CI. Sentence recognition in the various noise conditions show significant bilateral improvement over time, i.e. in the condition S0N0 from -3.1 dB preoperatively to -5.7 dB after 12 months. Localization improved bilaterally compared with the NH ear alone up to 10° RMS. The 8 participants wore the CI full time, and subjective reports were positive. Conclusion: Overall, the CI recipients with unilateral deafness obtained open-set speech recognition in quiet and in noise and improved localization. However, careful patient selection is a decisive factor for a successful treatment of this patient group. Under these conditions, CI implantation is a viable treatment of single sided deaf subjects. [ABSTRACT FROM AUTHOR]

Objective: Electrode insertion into the cochlea lead to significant pressure changes inside the cochlea with assumed effects on the functionality of the cochlea in terms of residual hearing. Fluid dynamics underline the importance of pressure changes close to inserted things. The aim of the study was to observe the occurence of pressure changes during electrode insertion at the cochlea implant electrode. Methods: The experiments were performed in different artificial cochlear models. A micro fibre pressure sensor was attached to a cochlear implant electrode at two different positions of the electrode and inserted at different speeds. Results: We observed significant pressure differences in terms of sensor position and depth of insertion. Conclusion: In our model experiments intracochlear pressure changes during cochlear implant electrode insertion are influenced by sensor position. [ABSTRACT FROM AUTHOR]

Objective: Perimodiolar position of CI electrodes is known for less electrophysiological channel interaction. Although designed for a perimodiolar position homogenous wrapping is not reached in all cases of 532 insertions. Electrode pull back is a surgical option to further decrease modiolar distance of the electrode. It was the aim of the present study to observe the pull back behavior of the 532 electrode. Method: In a temporal bone study with 5 decapped temporal bones of different sizes a video tracking observation of the behavior of the 532 electrode was performed. Results: We observed a relation between temporal bone size, initial insertion depth and pull back effect. Conclusion: Defined electrode pull back allows a homogenous wrapping of the 532 electrode to the modiolous. [ABSTRACT FROM AUTHOR]

Introduction: Recent advances in the knowledge about handling MRI artefacts and the pain-free performance of MRI scans in cochlear implantees showed that an estimation of the intracochlear electrode position is possible at 1,5 T with perimodiolar or midmodiolar arrays. The aim of the study was to evaluate the assessment of the ipsilateral scalar position of the cochlear implant's lateral wall electrodes by MRI sequences at 3 T. Methods: In a prospective study we evaluated 10 patients implanted with a diametrically bipolar implant magnet system with a lateral wall electrode in an axial and coronal position and a T2 weighted sequence at 3 T. We compared the evaluated intracochlear position with the routinely postoperative performed CBCT scan observed position. Results: In all cases the MRT-estimated scalar position corresponded with the CBCT scan estimated position. In all cases a scala tympani position was assumed. While the position in the basal turn is reliably localisable, the firstturn visual assessment is difficult. A translocation as a visual couterpart is missing in our series. Conclusion: An estimation of the intracochlear position of lateral wall cochlear implant electrodes by 3 T MRI is possible for the basal turn. The electrode design plays a major role for the visual assessment. [ABSTRACT FROM AUTHOR]

Introduction: Electrode shape and diameter can play an important role in preservation of residual hearing and more important in hearing outcome after cochlear implantation. Roughly there can be distinguished between straight and precurved electrodes of different diameters. Recently there has been developed a new straight electrode, the Slim J Electrode ®, manufactured by Advanced Bionics ® Company. It was aim of the study to investigate insertion feasibility and first hearing results. Methods and Materials: 10 patients, 5 provided with an AB Midscala Electrode and 5 provided with the new Slim J Electrode by two surgeons, matched according to age and pre-operative residual hearing, were evaluated as far as pre and postoperative residual hearing and postoperative speech understanding after 3 months are concerned. Additionally development of ECAP (electrically evoked action potentials) values was analyzed and position of electrodes was determined using intraoperative flat panel technology. Insertion properties were documented by surgical staff. Results: There were no difficulties and pitfalls concerning the insertion mode. All electrodes were placed regularly and showed a position next to the cochlear modiolus (Midscala) and next to the outer cochlear circumference (Slim J) respectively. Residual hearing could be preserved in both groups in a comparable number of patients. ECAP values showed an analog performance to earlier measurements with different electrode shapes as the perimodiolar electrode presents lower thresholds than the straight one. Discussion/Conclusion: The new straight Slim J Electrode® represents a useful supplement to the existing opportunities of electrodes and has similar properties as far as short term preservation of residual hearing is concerned. [ABSTRACT FROM AUTHOR]

Objective: The duration of deafness and the ECAP threshold are known factors correlating with the audiological outcome of cochlear implantees. Different factors are known to affect the NRT threshold like surgical factors, electrode design and the insertional depth. The nucleus slim straight electrode gives the surgeon an insertional orientation with a contralateral to the electrode contact direction attached wing. The aim of this study was to observe the correlation between NRT threshold and the contact orientation for slim straight electrode arrays. Materials and Methods: In a retrospective controlled study in a tertiary referral center the electrophysiological data sets of 35 patients with measured intraoperative Auto- NRTs and postoperative MSCT were evaluated. Additonally insertions in temporal bones were performed to further evaluate the insertional behavior of Nucleus slim straight electrodes. In a prospective part of the study different wing orientations during insertion were performed and NRT thresholds were measured. Results: By the electrophysiological evaluation of 35 patients discorrelations between the NRT threshold between left and right side insertions were observed. Temporal bone observations showed a non torsional behavior of the slim straight electrode related to a wing related malinsertion. Electrode positions with different contact orientations have no impact on the NRT threshold. Conclusion: Electrode wing orientation during insertion has no impact on the NRT threshold of Nucleus slim straight electrodes. [ABSTRACT FROM AUTHOR]