[Concept and implementation of an adaptive digital hearing training system for cochlear implant aftercare]. / Konzept und Umsetzung eines adaptiven digitalen Hörtrainingssystems für die Cochlea-Implantatnachsorge.

BACKGROUND AND OBJECTIVE: Within the context of an interdisciplinary research project, we created a cutting-edge prototype of an adaptive digital auditory training system designed for cochlear implant (CI) users. By leveraging the evidence-centered design (ECD) framework, we integrated a dynamic difficulty adjustment feature that tailors the experience to the unique performance capabilities of each individual user. METHODS: The ECD provides a conceptual design framework suitable for complex assessments of competence and dynamic performance. In the first phase, the domain of hearing was first defined in the context of CI users. In the development phase the three core models of the ECD, the competence model, the evidence model, and the task model, were developed and implemented. In addition, an asset pool of sound and language files was created, which included comprehensive linguistic feature descriptions for calculating item difficulties. RESULTS: Based on the requirements described, an adaptive exercise generator, an AI service, and other components were implemented. This included the development of a game environment and a dashboard for patient data management. The exercises' difficulty levels were determined based on various parameters (e.g., sound, word frequency and number of words, grammatical properties) in combination with defined task types and levels. CONCLUSION: An adaptive digital auditory training system can help to supervise and train CI patients in a continuous, interactive process based on their individual needs. We see the ECD as an effective way to build a user-based adaptive system.

Accuracy of Electrode Position in Sphenopalatine Ganglion Stimulation in Correlation With Clinical Efficacy.

INTRODUCTION: Sphenopalatine ganglion (SPG) stimulation is an efficient treatment for cluster headache. The target for the SPG microstimulator in the pterygopalatine fossa lies between the vidian canal and foramen rotundum, ideally two contacts should be placed in this area. However, placement according to the manufacturers recommendations is frequently not possible. It is not known whether a suboptimal electrode placement interferes with postoperative outcomes. MATERIALS AND METHODS: SPG stimulation was performed in 13 patients between 2015 and 2018 in a single center. Lead location was determined by intraoperative computed tomography scan and correlated with the planned lead position as well as clinical data and stimulation parameters. Patients with a reduction of 50% or more in pain intensity or frequency were considered responsive. RESULTS: Eleven patients (84.6%) responded to SPG stimulation with eight being frequency responders (61.5%). In seven cases, there were less than two electrodes between vidian canal and foramen rotundum, there was no significant correlation with negative stimulation results (p = 0.91). The mean distance of lead location between pre- and postoperative images did not correlate with clinical outcomes (p = 0.84) and was even bigger in responders (4.91 mm vs. 4.53 mm). The closest electrode contact to the vidian canal was in the stimulation area in all but one patient, regardless of its overall distance to canal. The distance of the closest electrode to the vidian canal was, however, not significantly correlated to the percentage of frequency (p = 0.68) or intensity reduction (p = 0.61). CONCLUSION: There was no significant correlation regarding aberrations of lead position from the planned position with clinical outcome. However, this study might be underpowered to detect such a correlation. The closest electrode contact to the vidian canal was in the stimulation area in all but one patient in the final programming. This indicates that, overall, the lead location does play a crucial role in SPG stimulation for cluster headache.

Patient quality of life after vestibular schwannoma removal: possibilities and limits to measuring different domains of patients' wellbeing.

PURPOSE: Since the 1980s, health-related quality of life (HRQOL) has been recognized in the assessment of medical treatment. To determine the health-related quality of life (HRQOL) of vestibular schwannoma (VS) patients, a specific questionnaire that has been validated in different languages is essential. METHODS: The Short Form-36 Health Survey (SF-36) and PANQOL questionnaires in German were evaluated in patients after removal of a VS via the translabyrinthine approach. Descriptive statistics of a comparison of the SF-36 results to those of a normal sample are illustrated. Criterion validity was investigated using Spearman's rank test to correlate the PANQOL domains with the SF-36 domains. A confirmatory factor analysis of the PANQOL was performed to determine the stability of the factor structure of the PANQOL questionnaire for our cohort. RESULTS: The criterion validity of the German PANQOL questionnaire is comparable to that of the original English version. The SF-36 domains values ranged from 49.31/100 (role physical) to 66.46/100 (physical functioning). Compared to the normal population, patients who underwent surgical removal of a VS showed a significantly reduced quality of life, mainly in domains such as physical and social functioning, as well as psychological wellbeing. CONCLUSION: The German PANQOL has been validated and is now available. Post-surgical treatment should be focused not only on physiological rehabilitation but also on improving the quality of life, especially aspects of psychological and social wellbeing.

Robotic cochlear implantation: feasibility of a multiport approach in an ex vivo model.

PURPOSE: A recent clinical trial has shown the feasibility of robotic cochlear implantation. The electrode was inserted through the robotically drilled tunnel and an additional access through the external auditory canal was created to provide for means of visualization and manipulation. To obviate the need for this additional access, the utilization of multiple robotically drilled tunnels targeting the round window has been proposed. The objective of this study was to assess the feasibility of electrode insertion through a robotic multiport approach. METHODS: In four ex vivo human head specimens (left side), four trajectories through the facial recess (2x) and the retrofacial and suprameatal region were planned and robotically drilled. Optimal three-port configurations were determined for each specimen by analyzing combinations of three of the four trajectories, where the three trajectories were used for the electrode, endoscopic visualization and manipulative assistance. Finally, electrode insertions were conducted through the optimal configurations. RESULTS: The electrodes could successfully be inserted, and the procedure sufficiently visualized through the facial recess drill tunnels in all specimens. Effective manipulative assistance for sealing the round window could be provided through the retrofacial tunnel. CONCLUSIONS: Electrode insertion through a robotic three-port approach is feasible. Drill tunnels through the facial recess for the electrode and endoscope allow for optimized insertion angles and sufficient visualization. Through a retrofacial tunnel effective manipulation for sealing is possible.

Multistep translation and cultural adaptation of the Penn acoustic neuroma quality-of-life scale for German-speaking patients.

BACKGROUND: Monitoring the health-related quality of life (HRQOL) for patients with vestibular schwannoma (VS) has garnered increasing interest. In German-speaking countries, there is no disease-specific questionnaire available similar to the "Penn Acoustic Neuroma Quality-of-life Scale" (PANQOL). METHOD: We translated the PANQOL for German-speaking patients based on a multistep protocol that included not only a forward-backward translation but also linguistic and sociocultural adaptations. The process consists of translation, synthesis, back translation, review by an expert committee, administration of the prefinal version to our patients, submission and appraisal of all written documents by our research team. The required multidisciplinary team for translation comprised head and neck surgeons, language professionals (German and English), a professional translator, and bilingual participants. A total of 123 patients with VS underwent microsurgical procedures via different approaches at our clinic between January 2007 and January 2017. Among these, 72 patients who underwent the translabyrinthine approach participated in the testing of the German-translated PANQOL. RESULT: The first German version of the PANQOL questionnaire was created by a multistep translation process. The responses indicate that the questionnaire is simple to administer and applicable to our patients. CONCLUSION: The use of a multistep process to translate quality-of-life questionnaires is complex and time-consuming. However, this process was performed properly and resulted in a version of the PANQOL for assessing the quality of life of German-speaking patients with VS.

[Hearing rehabilitation with the cochlea implant following translabyrinthine CPA tumor removal ?] / Hörrehabilitation durch Cochlea-Implantation nach Vestibularisschwannom-Entfernung?

We present a quality analysis of 10 patients with an individual treatment trial for a simultaneous or consecutive cochlea implantation after translabyrinthine removal of a neurinoma at the cerebellopontine angle. The results show that most of the patients benefit from the cochlea implantation after unilateral deafness. Through a careful surgical preparation technique at the inner ear canal and its surroundings the morphological and functional integrity of the neurovascular structures can be guaranteed.

[E-learning in ENT: Usage in University Medical Centers in Germany]. / Einsatz von E-Learning an deutschen Universitäts-HNO-Kliniken.

E-learning is an essential part of innovative medical teaching concepts. The challenging anatomy and physiology in ENT is considered particularly suitable for self-assessed and adaptive e-learning. Usage and data on daily experience with e-learning in German ENT-university hospitals are currently unavailable and the degree of implementation of blended learning including feed-back from medical students are currently not known. We investigated the current need and usage of e-learning in academic ENT medical centers in Germany. We surveyed students and chairs for Otorhinolaryngology electronically and paperbased during the summer semester 2015. Our investigation revealed an overall heterogenous picture on quality and quantity of offered e-learning applications. While the overall amount of e-learning in academic ENT in Germany is rather low, at least half of the ENT-hospitals in medical faculties reported that e-learning had improved their own teaching activities. More collaboration among medical faculties and academic ENT-centers may help to explore new potentials, overcome technical difficulties and help to realize more ambitious projects.

Cochlear obliteration after translabyrinthine vestibular schwannoma surgery.

The objective of the study was to determine the temporal occurrence of cochlear obliteration following translabyrinthine vestibular schwannoma resection. A retrospective chart review, cross-sectional study, and sequential analysis of the time series were performed. The retrospective study included patients undergoing translabyrinthine resection for stage T1-T2 vestibular schwannoma from 2007 to 2010 without prior therapy and postoperative follow-up including MRI of the brain and the cerebellopontine angle. Already 3 months after surgery a radiographic labyrinthine change was observed in 66.7 %, a partial obstruction in 50 %, and an obstruction limited to the saccule in 16.7 %. Only 33.3 % of the patients showed an unchanged inner ear. In consideration of early cochlear obstruction after translabyrinthine vestibular schwannoma resection, temporary follow-up is necessary. Since the indications for cochlear implantation (CI) have been extended, especially concerning patients with single-side deafness, a simultaneous or early second-stage CI after tumour removal should be discussed.

Development of a new endoscope holder for head and neck surgery--from the technical design concept to implementation.

Endoscope holders are utilized by a variety of surgeons but are not commonplace in head and neck surgery. The SOLOASSIST active camera holder, which is currently used for abdominal surgery, will soon be adapted for head and neck surgery in collaboration with AKTORmed GmbH SOLO SURGERY (Barbing, Germany). In our pre-feasibility study, we analyzed the use of the existing endoscope holder on anatomical specimens during head and neck surgery. Based on these results, we are proceeding towards the development of a new endoscope holder for head and neck surgery. First, we drafted the technical concepts and discussed the advantages and disadvantages of the system. Then, we used anatomic specimens to measure the forces that occur intraoperatively during sinus surgery. Next, we designed a computer-aided design (CAD) model. Finally, we developed the first production prototype and used it for a frontal skull base procedure on an anatomical specimen. We present the three most promising concepts for a new holder. The resulting total force (F res = √(X (2) + Y (2) + Z (2))) was calculated to be 3.2 N during sinus surgery. We could observe all necessary intraoperative landmarks with the endoscope and its holder in a sinus and frontal skull base surgery. We developed a production prototype of a new endoscope holder and demonstrate satisfactory results in the use of anatomic specimens for skull base surgery.

Toward an interoperable, intraoperative situation recognition system via process modeling, execution, and control using the standards BPMN and CMMN.

PURPOSE: For the modeling, execution, and control of complex, non-standardized intraoperative processes, a modeling language is needed that reflects the variability of interventions. As the established Business Process Model and Notation (BPMN) reaches its limits in terms of flexibility, the Case Management Model and Notation (CMMN) was considered as it addresses weakly structured processes. METHODS: To analyze the suitability of the modeling languages, BPMN and CMMN models of a Robot-Assisted Minimally Invasive Esophagectomy and Cochlea Implantation were derived and integrated into a situation recognition workflow. Test cases were used to contrast the differences and compare the advantages and disadvantages of the models concerning modeling, execution, and control. Furthermore, the impact on transferability was investigated. RESULTS: Compared to BPMN, CMMN allows flexibility for modeling intraoperative processes while remaining understandable. Although more effort and process knowledge are needed for execution and control within a situation recognition system, CMMN enables better transferability of the models and therefore the system. Concluding, CMMN should be chosen as a supplement to BPMN for flexible process parts that can only be covered insufficiently by BPMN, or otherwise as a replacement for the entire process. CONCLUSION: CMMN offers the flexibility for variable, weakly structured process parts, and is thus suitable for surgical interventions. A combination of both notations could allow optimal use of their advantages and support the transferability of the situation recognition system.

Cochlear Implantation in Single-Sided Deafness and Asymmetric Hearing Loss: 12 Months Follow-up Results of a European Multicenter Evaluation.

People with single-sided deafness (SSD) or asymmetric hearing loss (AHL) have particular difficulty understanding speech in noisy listening situations and in sound localization. The objective of this multicenter study is to evaluate the effect of a cochlear implant (CI) in adults with single-sided deafness (SSD) or asymmetric hearing loss (AHL), particularly regarding sound localization and speech intelligibility with additional interest in electric-acoustic pitch matching. A prospective longitudinal study at 7 European tertiary referral centers was conducted including 19 SSD and 16 AHL subjects undergoing cochlear implantation. Sound localization accuracy was investigated in terms of root mean square error and signed bias before and after implantation. Speech recognition in quiet and speech reception thresholds in noise for several spatial configurations were assessed preoperatively and at several post-activation time points. Pitch perception with CI was tracked using pitch matching. Data up to 12 months post activation were collected. In both SSD and AHL subjects, CI significantly improved sound localization for sound sources on the implant side, and thus overall sound localization. Speech recognition in quiet with the implant ear improved significantly. In noise, a significant head shadow effect was found for SSD subjects only. However, the evaluation of AHL subjects was limited by the small sample size. No uniform development of pitch perception with the implant ear was observed. The benefits shown in this study confirm and expand the existing body of evidence for the effectiveness of CI in SSD and AHL. Particularly, improved localization was shown to result from increased localization accuracy on the implant side.

European multi-centre study of the Nucleus Hybrid L24 cochlear implant.

OBJECTIVES: To investigate the preservation of residual hearing in subjects who received the Nucleus Hybrid L24 cochlear implant. To investigate the performance benefits up to one year post-implantation in terms of speech recognition, sound quality, and quality of life. DESIGN: Prospective, with sequential enrolment and within-subject comparisons. Post-operative performance using a Freedom Hybrid sound processor was compared with that of pre-operative hearing aids. STUDY SAMPLE: Sixty-six adult hearing-impaired subjects with bilateral severe-to-profound high frequency hearing loss. RESULTS: Group median increase in air-conduction thresholds in the implanted ear for test frequencies 125-1000 Hz was < 15 dB across the population; both immediately and one year post-operatively. Eighty-eight percent of subjects used the Hybrid processor at one year post-op. Sixty-five percent of subjects had significant gain in speech recognition in quiet, and 73% in noise (≥ 20 percentage points/2 dB SNR). Mean SSQ subscale scores were significantly improved (+ 1.2, + 1.3, + 1.8 points, p < 0.001), as was mean HUI3 score (+ 0.117, p < 0.01). Combining residual hearing with CI gave 22-26 %age points mean benefit in speech recognition scores over CI alone (p < 0.01). CONCLUSIONS: Useful residual hearing was conserved in 88% of subjects. Speech perception was significantly improved over preoperative hearing aids, as was sound quality and quality of life.

FGF9-Associated Multiple Synostoses Syndrome Type 3 in a Multigenerational Family.

Multiple synostoses syndrome (OMIM: #186500, #610017, #612961, #617898) is a genetically heterogeneous group of autosomal dominant diseases characterized by abnormal bone unions. The joint fusions frequently involve the hands, feet, elbows or vertebrae. Pathogenic variants in FGF9 have been associated with multiple synostoses syndrome type 3 (SYNS3). So far, only five different missense variants in FGF9 that cause SYNS3 have been reported in 18 affected individuals. Unlike other multiple synostoses syndromes, conductive hearing loss has not been reported in SYNS3. In this report, we describe the clinical and selected radiological findings in a large multigenerational family with a novel missense variant in FGF9: c.430T>C, p.(Trp144Arg). We extend the phenotypic spectrum of SYNS3 by suggesting that cleft palate and conductive hearing loss are part of the syndrome and highlight the high degree of intrafamilial phenotypic variability. These findings should be considered when counseling affected individuals.

Petasol butenoate complex (Ze 339) relieves allergic rhinitis-induced nasal obstruction more effectively than desloratadine.

BACKGROUND: Allergic rhinitis symptoms of itching, sneezing, rhinorrhea, and nasal obstruction significantly decrease patients' quality of life. Compared with histamine and leukotriene receptor antagonists, the petasol butenoate complex Ze 339 displays pharmacologically distinct properties. In vitro it inhibits the biosynthesis of leukotrienes and mediator release from activated eosinophils. OBJECTIVE: This study aimed to assess the efficacy and mode of action of Ze 339, desloratadine, and placebo on allergic rhinitis symptoms, nasal airflow, and local mediator levels after unilateral nasal allergen provocation. METHODS: In this double-blind, randomized, crossover study 18 subjects with allergic rhinitis to grass pollen received Ze 339, desloratadine, and placebo for 5 days before nasal allergen challenge with grass pollen extract. Rhinomanometry, symptom assessment, and local inflammatory mediator measurement were performed during the 24 hours after allergen challenge. RESULTS: With Ze 339, the patient's time to recovery (5.4 ± 1.6 hours) from nasal obstruction after allergen challenge (time for return to 90% of baseline value ± SEM) was significantly shorter than with placebo (9.1 ± 2.3 hours, P = .035) and desloratadine (10.7 ± 2.5 hours, P = .022). Likewise, Ze 339's standardized symptom assessment for nasal obstruction (3.2 ± 1.3 hours) showed significantly faster relief (time for return to baseline value ± SEM compared with placebo, 8.3 ± 2.4 hours; P = .027) and desloratadine (4.5 ± 1.2 hours, P = .030). One interesting finding was that Ze 339 significantly reduced IL-8 and leukotriene B(4) levels in nasal secretions before challenge. CONCLUSION: When compared with desloratadine and placebo, Ze 339 shows better efficacy in relieving nasal obstruction symptoms and inhibiting critical components of the chemokine network and as such represents a novel symptomatic and possible prophylactic treatment for allergic rhinitis.

Continuous Feature-Based Tracking of the Inner Ear for Robot-Assisted Microsurgery.

Robotic systems for surgery of the inner ear must enable highly precise movement in relation to the patient. To allow for a suitable collaboration between surgeon and robot, these systems should not interrupt the surgical workflow and integrate well in existing processes. As the surgical microscope is a standard tool, present in almost every microsurgical intervention and due to it being in close proximity to the situs, it is predestined to be extended by assistive robotic systems. For instance, a microscope-mounted laser for ablation. As both, patient and microscope are subject to movements during surgery, a well-integrated robotic system must be able to comply with these movements. To solve the problem of on-line registration of an assistance system to the situs, the standard of care often utilizes marker-based technologies, which require markers being rigidly attached to the patient. This not only requires time for preparation but also increases invasiveness of the procedure and the line of sight of the tracking system may not be obstructed. This work aims at utilizing the existing imaging system for detection of relative movements between the surgical microscope and the patient. The resulting data allows for maintaining registration. Hereby, no artificial markers or landmarks are considered but an approach for feature-based tracking with respect to the surgical environment in otology is presented. The images for tracking are obtained by a two-dimensional RGB stream of a surgical microscope. Due to the bony structure of the surgical site, the recorded cochleostomy scene moves nearly rigidly. The goal of the tracking algorithm is to estimate motion only from the given image stream. After preprocessing, features are detected in two subsequent images and their affine transformation is computed by a random sample consensus (RANSAC) algorithm. The proposed method can provide movement feedback with up to 93.2 µm precision without the need for any additional hardware in the operating room or attachment of fiducials to the situs. In long term tracking, an accumulative error occurs.

Retrospective in silico evaluation of optimized preoperative planning for temporal bone surgery.

PURPOSE: Robot-assisted surgery at the temporal bone utilizing a flexible drilling unit would allow safer access to clinical targets such as the cochlea or the internal auditory canal by navigating along nonlinear trajectories. One key sub-step for clinical realization of such a procedure is automated preoperative surgical planning that incorporates both segmentation of risk structures and optimized trajectory planning. METHODS: We automatically segment risk structures using 3D U-Nets with probabilistic active shape models. For nonlinear trajectory planning, we adapt bidirectional rapidly exploring random trees on Bézier Splines followed by sequential convex optimization. Functional evaluation, assessing segmentation quality based on the subsequent trajectory planning step, shows the suitability of our novel segmentation approach for this two-step preoperative pipeline. RESULTS: Based on 24 data sets of the temporal bone, we perform a functional evaluation of preoperative surgical planning. Our experiments show that the automated segmentation provides safe and coherent surface models that can be used in collision detection during motion planning. The source code of the algorithms will be made publicly available. CONCLUSION: Optimized trajectory planning based on shape regularized segmentation leads to safe access canals for temporal bone surgery. Functional evaluation shows the promising results for both 3D U-Net and Bézier Spline trajectories.

i3PosNet: instrument pose estimation from X-ray in temporal bone surgery.

PURPOSE: Accurate estimation of the position and orientation (pose) of surgical instruments is crucial for delicate minimally invasive temporal bone surgery. Current techniques lack in accuracy and/or line-of-sight constraints (conventional tracking systems) or expose the patient to prohibitive ionizing radiation (intra-operative CT). A possible solution is to capture the instrument with a c-arm at irregular intervals and recover the pose from the image. METHODS: i3PosNet infers the position and orientation of instruments from images using a pose estimation network. Said framework considers localized patches and outputs pseudo-landmarks. The pose is reconstructed from pseudo-landmarks by geometric considerations. RESULTS: We show i3PosNet reaches errors [Formula: see text] mm. It outperforms conventional image registration-based approaches reducing average and maximum errors by at least two thirds. i3PosNet trained on synthetic images generalizes to real X-rays without any further adaptation. CONCLUSION: The translation of deep learning-based methods to surgical applications is difficult, because large representative datasets for training and testing are not available. This work empirically shows sub-millimeter pose estimation trained solely based on synthetic training data.

Evolution and Stagnation of Image Guidance for Surgery in the Lateral Skull: A Systematic Review 1989-2020.

Objective: Despite three decades of pre-clinical and clinical research into image guidance solutions as a more accurate and less invasive alternative for instrument and anatomy localization, translation into routine clinical practice for surgery in the lateral skull has not yet happened. The aim of this review is to identify challenges that need to be solved in order to provide image guidance solutions that are safe and beneficial for use during lateral skull surgery and to synthesize factors that facilitate the development of such solutions. Methods: Literature search was conducted via PubMed using terms relating to image guidance and the lateral skull. Data extraction included the following variables: image guidance error, imaging resolution, image guidance system, tracking technology, registration method, study endpoints, clinical target application, and publication year. A subsequent search of FDA 510(k) database for identified image guidance systems and extraction of the year of approval, intended use, and indications for use was performed. The study objectives and endpoints were subdivided in three time phases and summarized. Furthermore, it was analyzed which factors correlated with the image guidance error. Factor values for which an error ≤0.5 mm (µerror + 3σerror) was measured in more than one study were identified and inspected for time trends. Results: A descriptive statistics-based summary of study objectives and findings separated in three time intervals is provided. The literature provides qualitative and quantitative evidence that image guidance systems must provide an accuracy ≤0.5 mm (µerror + 3σerror) for their safe and beneficial application during surgery in the lateral skull. Spatial tracking accuracy and precision and medical image resolution both correlate with the image guidance accuracy, and all of them improved over the years. Tracking technology with accuracy ≤0.05 mm, computed tomography imaging with slice thickness ≤0.2 mm, and registration based on bone-anchored titanium fiducials are components that provide a sufficient setting for the development of sufficiently accurate image guidance. Conclusion: Image guidance systems must reliably provide an accuracy ≤0.5 mm (µerror + 3σerror) for their safe and beneficial use during surgery in the lateral skull. Advances in tracking and imaging technology contribute to the improvement of accuracy, eventually enabling the development and wide-scale adoption of image guidance solutions that can be used safely and beneficially during lateral skull surgery.

New strategies for high precision surgery of the temporal bone using a robotic approach for cochlear implantation.

The aim of the study was to demonstrate a collision-free trajectory of an instrument through the facial recess to the site of planned cochleostomy guided by a surgery robot. The indication for cochlear implantation is still expanding toward more substantial residual hearing. A cochleostomy as atraumatic as possible will influence the preservation of inner ear function. The employment of a highly precise instrument guidance using a robot could represent a feasible solution for a constant reproducible surgical procedure. Screw markers for a point-based registration were fixed on a human temporal bone specimen prepared with a mastoidectomy and posterior tympanotomy. A DICOM dataset has been generated thereof in a 64-multislice computer tomography (CT). A virtual trajectory in a 3D model has been planned representing the path of instrumentation toward the desired spot of cochleostomy. A 1.9-mm endoscope has been mounted onto the robot system RobaCKa (Staeubli RX90CR) to visualize this trajectory. The target registration error added up to 0.25 mm, which met the desirable tolerance of <0.5 mm. A collision-free propagation of the endoscope into the tympanic cavity via the facial recess has been performed by the robot and the spot of cochleostomy could be visualized through the endoscope. Using a DICOM dataset of a high-resolution CT and a robot as a positioning platform for surgical instruments could be a feasible approach to perform a highly precise and constant reproducible cochleostomy. Furthermore, it could be a crucial step to preserve substantial residual hearing in terms of expanding the indications for cochlear implantation.

Impact of room acoustic parameters on speech and music perception among participants with cochlear implants.

OBJECTIVES: Besides numerous other factors, listening experience with cochlear implants is substantially impaired by room acoustics. Even for persons without hearing impairment, the perception of auditory scenes, for example, concerning speech intelligibility, acoustic quality or audibility, is considerably influenced by room acoustics. For CI users, complex listening environments are usually associated with heavy losses. The aim of the present study was to determine room acoustic criteria that particularly influence speech pleasantness for CI users. DESIGN: Accordingly, speech material of the Oldenburg Sentence Test (Oldenburger Satztest, OLSA) as well as basic music material (major and minor triads) were auralized using the software Auratorium which allows auralization of simulated rooms. The constructed rooms for speech stimuli were based on the standard DIN 18041:2016-03 concerning acoustic quality in rooms, the binding standard referred to by room acoustic consultants in Germany, which also includes specifications for inclusive applications in schools. For the music perception tests, two typical concert halls of different sizes were modelled. The auralized test stimuli were unilaterally presented to 10 CI users via their auxiliary input as well as to 18 participants with typical hearing via headphones (control group). Speech pleasantness was evaluated using modified MUSHRA tests. Concerning music perception, chord discrimination was tested using paired comparisons. RESULTS: A strong preference of small source to listener distances by CI users was found, but no significant preference for room acoustic attenuation which exceeded the recommended for inclusive applications in schools. The analyses of the energy-time-structures suggested that a dense concentration of early reflections makes a beneficial impact on CI listeners' pleasantness ratings. Music materials were distinguished more consistently without any room acoustic impact, while any room acoustic impact led to performance close to chance level. This effect is probably due to spectral smearing effects caused by reverberation. CONCLUSIONS: These results suggest that in terms of pleasantness of speech, for CI-users, source-to-listener distance is the more influential parameter than room attenuation which goes beyond the German standard recommendation. Reflections from which CI users can benefit seem to occur much earlier than those from which NH listeners benefit. Future studies on chord discrimination concerning room acoustics are needed.