Free-Field Hearing Test in Noise with Free Head Rotation for Evaluation of Monaural Hearing.

There is a discrepancy between the hearing test results in patients with single-sided deafness (SSD) and their reported outcome measures. This is probably due to the presence of two elements in everyday situations: noise and head movements. We developed a stereo-audiometric test in noise with free head movements to evaluate movements and auditory performance in monaural and binaural conditions in normal hearing volunteers with one occluded ear. Tests were performed in the binaural condition (BIN), with the left ear (LEO) or the right ear occluded (REO). The signal was emitted by one of the seven speakers, placed every 30° in a semicircle, and the noise (cocktail party) by all speakers. Subjects turned their head freely to obtain the most comfortable listening position, then repeated 10 sentences in this position. In monaural conditions, the sums of rotations (head rotations for an optimal hearing position in degrees, random signal azimuth, 1 to 15 signal ad lib signal presentations) were higher (LEO 255 ± 212°, REO 308 ± 208° versus BIN 74 ± 76, p < 0.001, ANOVA) than those in the BIN condition and the discrimination score (out of 10) was lower than that in the BIN condition (LEO 5 ± 1, REO 7 ± 1 versus BIN 8 ± 1, respectively p < 0.001 and p < 0.05 ANOVA). In the monaural condition, total rotation and discrimination in noise were negatively correlated with difficulty (Pearson r = -0.68, p < 0.01 and -0.51, p < 0.05, respectively). Subjects' behaviors were different in optimizing their hearing in noise via head rotation. The evaluation of head movements seems to be a significant parameter in predicting the difficulty of monaural hearing in noisy environments.

Image-to-Patient Registration in Computer-Assisted Surgery of Head and Neck: State-of-the-Art, Perspectives, and Challenges.

Today, image-guided systems play a significant role in improving the outcome of diagnostic and therapeutic interventions. They provide crucial anatomical information during the procedure to decrease the size and the extent of the approach, to reduce intraoperative complications, and to increase accuracy, repeatability, and safety. Image-to-patient registration is the first step in image-guided procedures. It establishes a correspondence between the patient's preoperative imaging and the intraoperative data. When it comes to the head-and-neck region, the presence of many sensitive structures such as the central nervous system or the neurosensory organs requires a millimetric precision. This review allows evaluating the characteristics and the performances of different registration methods in the head-and-neck region used in the operation room from the perspectives of accuracy, invasiveness, and processing times. Our work led to the conclusion that invasive marker-based methods are still considered as the gold standard of image-to-patient registration. The surface-based methods are recommended for faster procedures and applied on the surface tissues especially around the eyes. In the near future, computer vision technology is expected to enhance these systems by reducing human errors and cognitive load in the operating room.

Delay and Acceleration Threshold of Movement Perception in Patients Suffering from Vertigo or Dizziness.

BACKGROUND: The objective was to evaluate the delay and the acceleration threshold (AT) of movement perception in a population of patients suffering from dizziness and analyze the factors influencing these parameters. METHODS: This prospective study included 256 adult subjects: 16 control and 240 patients (5 acute unilateral vestibular loss, 13 compensated unilateral loss, 32 Meniere diseases, 48 persistent postural-perceptual dizziness (PPPD), 95 benign paroxysmal positional vertigo (BPPV), 10 central cases, 19 bilateral vestibulopathy, 14 vestibular migraine, and 4 age-related dizziness). Patients were evaluated for the sound-movement synchronicity perception (maximum delay between the bed oscillation peak and a beep perceived as synchronous, PST) and AT during a pendular movement on a swinging bed. RESULTS: We observed higher PST in women and in senior patients regardless of etiology. AT was higher in senior patients. AT was not influenced by etiology except in patients with bilateral vestibulopathy who had higher thresholds. AT was related to unipodal stance performance, past history of fall, and stop-walking-when-talking test. CONCLUSIONS: Delay and acceleration thresholds appear to be coherent with clinical findings and open insights on the exploration of symptoms that cannot be explained by routine otoneurological tests.

The French way of voice rehabilitation post total laryngectomy: current clinical practices and tendencies.

BACKGROUND: Vocal rehabilitation post total laryngectomy (TL) lacks clinical guidelines, especially with the presence of multiple modalities. OBJECTIVES: To describe the tendencies of vocal rehabilitation post TL in France and compare it with other countries. We try to identify the most practiced modalities and recognize statistically significant influencing factors. MATERIALS AND METHODS: An electronic anonymous survey was answered by 75 ENT surgeons from France. The survey outlined the common practiced vocal rehabilitation modalities and had two versions depending on if the participant practices the tracheoesophageal speech (TES) or not. RESULTS: 96% use TES in their practice. Single modality TES and double modality TES with esophageal speech (ES) are the two most practiced modalities. 99% agreed that there is no age limit for the TES. Single modality ES was offered 92% more when more than 10 TL were performed per year (p < .05). No influencing factors found for single modality TES or double modality TES with ES (p > .05).Conclusion: In line with tendencies from other countries, the TES is the most practiced modality of vocal rehabilitation coupled or not with the ES. TES has no age limit as per our participants. The least practiced modality is the singe modality ALS.

Effects of saccade delay, side of deficit, and training on detection of catch-up saccades during head-impulse test in virtual-reality-enhanced mannequin.

In this study, a training simulator for the examination of dizzy patients based on a virtual-reality-enhanced mannequin (VREM) was developed to evaluate the detection of catch-up saccades during head impulse test (HIT) and the effect of training in VREM. For novices (n = 35), 2 trials were conducted before and after a training session. Experts (n = 7) were submitted to an evaluation session. In each trial, a left or a right horizontal canal deficit with an overt catch-up saccade (delay between 110 and 320 ms) was randomly presented. Participants scored the difficulty in performing the maneuver, in recognizing the saccades, and the self-confidence in the diagnosis using a visual analogue scale (VAS). Saccade delay significantly influenced the performance. Training significantly improved the sensitivity in the residents (69.1% before to 97.9% after the training, p < 0.001, Fisher's exact test, n = 560 tests), surpassing experts' performances (p < 0.001, versus 87% in experts, Fisher's exact test). The specificity also increased to the expert level (78% before to 95% after the training, and 95% in experts, p < 0.001, Fisher's exact test). The VAS showed a decrease difficulty to execute the HIT, with an increase in the confidence after training. VREM improved the HIT execution performance and the confidence in novice practitioners.

Confrontation of endolymphatic hydrops diagnosis on 3-Tesla MRI to clinical and audiovestibular findings in Meniere's disease.

Objective: The aim of this study was to compare different MRI diagnostic criteria for endolymphatic hydrops (EH) and to investigate the relation between audiovestibular and MRI findings in Meniere's disease (MD). Materials and methods: Prospective cross-sectional cohort study in 2 referral centers included 76 patients with unilateral (n = 62) or bilateral (n = 14) MD. All patients underwent inner ear 3T-MRI 4 h (n = 52) or >24H (n = 24) following audiovestibular tests. T2-CISS and 3D-FLAIR images 4H after gadolinium were obtained. EH diagnosis was based on saccular morphology on coronal views (T2 and 3D-FLAIR), semi quantitative estimation of endolymphatic space enlargement, and saccule utricle ratio inversion (SURI) on 3D-FLAIR axial views. Results: SURI was the best criterion related to the disease side (43 SURI+ on symptomatic ears, n = 77, vs. 6 SURI+ on asymptomatic ears, n = 53, p < 0.0001, Chi-2). Same-day MRI revealed relation between EH, hearing loss and caloric weakness which could not be detected on delayed MRI: SURI was associated with a higher pure-tone average (43 ± 4.1 dB in SURI+ ears, n = 42 vs. 23 ± 2.6 SURI-, n = 62, p < 0.0001, unpaired t-test,), and a higher proportion of vestibular caloric weakness (23/46 SURI+ ears vs. 4/62 SURI-, p < 0.001, Chi-2). Among all criteria, SURI combined to caloric weakness was the best predictor of the affected side in a logistic regression model. Conclusion: SURI had the strongest relation to the side the disease and audio vestibular findings for unilateral, probable and definite meniere disease. A short delay between MRI and audio vestibular tests improved the coherence between the findings.

Virtual-reality-enhanced mannequin to train emergency physicians to examine dizzy patients using the HINTS method.

Introduction: Acute vertigo is a frequent chief complaint in the emergency departments, and its efficient management requires thorough training. The HINTS protocol is a valid method to screen patients in the emergency room, but its application in routine is hindered by the lack of training. This study aimed to evaluate the training of emergency physicians for the HINTS method based on a mannequin-based virtual reality simulator (MBVRS). Methods: We conducted a monocenter, prospective, longitudinal, and randomized cohort study in an Emergency Department at a regional university hospital. We included 34 emergency physicians randomized into two equal groups matched by age and professional experience. The control group attended a theoretical lesson with video demonstrations and the test group received a simulation-based training in addition to the lecture. Results: We showed that the test group had a higher diagnosis performance for the HINTS method compared to the control group as evaluated by the simulator at 1 month (89% sensitivity versus 45, and 100% specificity versus 86% respectively, p < 001, Fisher's exact test). Evaluation at 6 months showed a similar advantage to the test group. Discussion: The MBVRS is a useful pedagogic tool for the HINTS protocol in the emergency department. The advantage of a unique training session can be measured up to 6 months after the lesson.

Effect of Sound Coding Strategies on Music Perception with a Cochlear Implant.

The goal of this study was to evaluate the music perception of cochlear implantees with two different sound processing strategies. Methods: Twenty-one patients with unilateral or bilateral cochlear implants (Oticon Medical®) were included. A music trial evaluated emotions (sad versus happy based on tempo and/or minor versus major modes) with three tests of increasing difficulty. This was followed by a test evaluating the perception of musical dissonances (marked out of 10). A novel sound processing strategy reducing spectral distortions (CrystalisXDP, Oticon Medical) was compared to the standard strategy (main peak interleaved sampling). Each strategy was used one week before the music trial. Results: Total music score was higher with CrystalisXDP than with the standard strategy. Nine patients (21%) categorized music above the random level (>5) on test 3 only based on mode with either of the strategies. In this group, CrystalisXDP improved the performances. For dissonance detection, 17 patients (40%) scored above random level with either of the strategies. In this group, CrystalisXDP did not improve the performances. Conclusions: CrystalisXDP, which enhances spectral cues, seemed to improve the categorization of happy versus sad music. Spectral cues could participate in musical emotions in cochlear implantees and improve the quality of musical perception.

Augmented Reality Based Transmodiolar Cochlear Implantation.

HYPOTHESIS: Transmodiolar auditory implantation via the middle ear cavity could be possible using an augmented reality system (ARS). BACKGROUND: There is no clear landmark to indicate the cochlear apex or the modiolar axis. The ARS seems to be a promising tool for transmodiolar implantation by combining information from the preprocedure computed tomography scan (CT-scan) images to the real-time video of the surgical field. METHODS: Eight human temporal bone resin models were included (five adults and three children). The procedure started by the identification of the modiolar axis on the preprocedure CT-scan followed by a 3D reconstruction of the images. Information on modiolar location and navigational guidance was supplemented to the reconstructed model, which was then registered with the surgical video using a point-based approach. Relative movements between the phantom and the microscope were tracked using image feature-based motion tracking. Based on the information provided via the ARS, the surgeon implanted the electrode-array inside the modiolus after drilling the helicothrema. Postprocedure CT-scan images were acquired to evaluate the registration error and the implantation accuracy. RESULTS: The implantation could be conducted in all cases with a 2D registration error of 0.4 ±â€Š0.24 mm. The mean entry point error was 0.6 ±â€Š1.00 mm and the implant angular error 13.5 ±â€Š8.93 degrees (n = 8), compatible with the procedure requirements. CONCLUSION: We developed an image-based ARS to identify the extremities and the axis of the cochlear modiolus on intraprocedure videos. The system yielded submillimetric accuracy for implantation and remained stable throughout the experimental study.

Vision-Based Augmented Reality System for Middle Ear Surgery: Evaluation in Operating Room Environment.

HYPOTHESIS: Augmented reality (AR) solely based on image features is achievable in operating room conditions and its precision is compatible with otological surgery. BACKGROUND: The objective of this work was to evaluate the performance of a vision-based AR system for middle ear surgery in the operating room conditions. METHODS: Nine adult patients undergoing ossicular procedures were included in this prospective study. AR was obtained by combining real-time video from the operating microscope with the virtual image obtained from the preoperative computed tomography (CT)-scan. Initial registration between the video and the virtual CT image was achieved using manual selection of six points on the tympanic sulcus. Patient-microscope movements during the procedure were tracked using image-feature matching algorithm. The microscope was randomly moved at an approximated speed of 5 mm/s in the three axes of space and rotation for 180 seconds. The accuracy of the system was assessed by calculating the distance between each fiducial point selected on the video image and its corresponding point on the scanner. RESULTS: AR could be obtained for at least 3 minutes in seven out of nine patients. The overlay fiducial and target registration errors were 0.38 ±â€Š0.23 mm (n = 7) and 0.36 ±â€Š0.15 mm (n = 5) respectively, with a drift error of 1.2 ±â€Š0.5 µm/s. The system was stable throughout the procedure and achieved a refresh rate of 12 fps. Moderate bleeding and introduction of surgical instruments did not compromise the performance of the system. CONCLUSION: The AR system yielded sub-millimetric accuracy and remained stable throughout the experimental study despite patient-microscope movements and field of view obtrusions.

Participation of Acoustic and Electric Hearing in Perceiving Musical Sounds.

Introduction: The objective of our study was to evaluate musical perception and its relation to the quality of life in patients with bimodal binaural auditory stimulation. Materials and Methods: Nineteen adult patients with a cochlear implant (CI) for minimum 6 months, and moderate to severe contralateral hearing loss with a hearing aid (HA), and 21 normal hearing adults were included in this prospective, cross-sectional study. Pure-tone and speech audiometry, musical test evaluating sound perception characteristics and musical listening abilities, Munich questionnaire for musical habits, and the APHAB questionnaire were recoded. Performance in musical perception test with HA, CI, and HA + CI, and potential correlations between music test, audiometry and questionnaires were investigated. Results: Bimodal stimulation improved musical perception in several features (sound brightness, roughness, and clarity) in comparison to unimodal hearing, but CI did not add to HA performances in texture, polyphony or musical emotion and even appeared to interfere negatively in pitch perception with HA. Musical perception performances (sound clarity, instrument recognition) appeared to be correlated to hearing-related quality of life (APHAB RV and EC subdomains) but not with speech performances suggesting that the exploration of musical perception complements speech understanding evaluation to better describe every-day life hearing handicap. Conclusion: Testing musical sound perception provides important information on hearing performances as a complement to speech audiometry and appears to be related to hearing-related quality of life.

Use of Super Paramagnetic Iron Oxide Nanoparticles as Drug Carriers in Brain and Ear: State of the Art and Challenges.

Drug delivery and distribution in the central nervous system (CNS) and the inner ear represent a challenge for the medical and scientific world, especially because of the blood-brain and the blood-perilymph barriers. Solutions are being studied to circumvent or to facilitate drug diffusion across these structures. Using superparamagnetic iron oxide nanoparticles (SPIONs), which can be coated to change their properties and ensure biocompatibility, represents a promising tool as a drug carrier. They can act as nanocarriers and can be driven with precision by magnetic forces. The aim of this study was to systematically review the use of SPIONs in the CNS and the inner ear. A systematic PubMed search between 1999 and 2019 yielded 97 studies. In this review, we describe the applications of the SPIONS, their design, their administration, their pharmacokinetic, their toxicity and the methods used for targeted delivery of drugs into the ear and the CNS.

Automatic segmentation of inner ear on CT-scan using auto-context convolutional neural network.

Temporal bone CT-scan is a prerequisite in most surgical procedures concerning the ear such as cochlear implants. The 3D vision of inner ear structures is crucial for diagnostic and surgical preplanning purposes. Since clinical CT-scans are acquired at relatively low resolutions, improved performance can be achieved by registering patient-specific CT images to a high-resolution inner ear model built from accurate 3D segmentations based on micro-CT of human temporal bone specimens. This paper presents a framework based on convolutional neural network for human inner ear segmentation from micro-CT images which can be used to build such a model from an extensive database. The proposed approach employs an auto-context based cascaded 2D U-net architecture with 3D connected component refinement to segment the cochlear scalae, semicircular canals, and the vestibule. The system was formulated on a data set composed of 17 micro-CT from public Hear-EU dataset. A Dice coefficient of 0.90 and Hausdorff distance of 0.74 mm were obtained. The system yielded precise and fast automatic inner-ear segmentations.

Curvilinear Multiplanar Reconstruction to Predict Useful Length and Diameter of Cochlear Lumen for Cochlear Implantation.

OBJECTIVE: Evaluate the useful length and the diameter of the cochlear lumen (CL) using routine imaging before cochlear implantation to study inter-individual variability and its impact on the insertion depth of the electrode carrier (EC). STUDY DESIGN: Prospective cross-sectional study. SETTING: Tertiary referral center. PATIENTS: Thirty-one preoperative and postimplantation temporal bone CT scans were analyzed by two investigators. INTERVENTION: Images were analyzed via orthogonal multiplanar reconstruction (Osirix) to measure the lengths of the entire CL and the basal turn. By means of curvilinear reconstruction, the CL was unfolded and the diameters of the CL and of the EC were measured every 2 mm from the round window (RW) to the apex. RESULTS: Very high-inter individual variability was found for the length of the basal turn (RSD > 1000%), the entire CL length (RSD > 800%), and the CL diameter at the RW (RSD > 600%). CL diameter was not correlated to the CL length. The inserted EC/total visible CL length ratio was 1.0 ±â€Š0.12. Reliability of the measures was acceptable for the CL length and the diameter at 16 mm from the RW (Crohnbach's alpha > 0.7, n = 31). CONCLUSION: CL length and diameter can be directly measured in a reliable manner by commercially available tools. These parameters potentially influence the EC insertion and should be assessed before cochlear implant surgery.

Augmented reality for inner ear procedures: visualization of the cochlear central axis in microscopic videos.

PURPOSE: Visualization of the cochlea is impossible due to the delicate and intricate ear anatomy. Augmented reality may be used to perform auditory nerve implantation by transmodiolar approach in patients with profound hearing loss. METHODS: We present an augmented reality system for the visualization of the cochlear axis in surgical videos. The system starts with an automatic anatomical landmark detection in preoperative computed tomography images based on deep reinforcement learning. These landmarks are used to register the preoperative geometry with the real-time microscopic video captured inside the auditory canal. Three-dimensional pose of the cochlear axis is determined using the registration projection matrices. In addition, the patient microscope movements are tracked using an image feature-based tracking process. RESULTS: The landmark detection stage yielded an average localization error of [Formula: see text] mm ([Formula: see text]). The target registration error was [Formula: see text] mm for the cochlear apex and [Formula: see text] for the cochlear axis. CONCLUSION: We developed an augmented reality system to visualize the cochlear axis in intraoperative videos. The system yielded millimetric accuracy and remained stable throughout the experimental study despite camera movements throughout the procedure in experimental conditions.

Video-based augmented reality combining CT-scan and instrument position data to microscope view in middle ear surgery.

The aim of the study was to develop and assess the performance of a video-based augmented reality system, combining preoperative computed tomography (CT) and real-time microscopic video, as the first crucial step to keyhole middle ear procedures through a tympanic membrane puncture. Six different artificial human temporal bones were included in this prospective study. Six stainless steel fiducial markers were glued on the periphery of the eardrum, and a high-resolution CT-scan of the temporal bone was obtained. Virtual endoscopy of the middle ear based on this CT-scan was conducted on Osirix software. Virtual endoscopy image was registered to the microscope-based video of the intact tympanic membrane based on fiducial markers and a homography transformation was applied during microscope movements. These movements were tracked using Speeded-Up Robust Features (SURF) method. Simultaneously, a micro-surgical instrument was identified and tracked using a Kalman filter. The 3D position of the instrument was extracted by solving a three-point perspective framework. For evaluation, the instrument was introduced through the tympanic membrane and ink droplets were injected on three middle ear structures. An average initial registration accuracy of 0.21 ± 0.10 mm (n = 3) was achieved with a slow propagation error during tracking (0.04 ± 0.07 mm). The estimated surgical instrument tip position error was 0.33 ± 0.22 mm. The target structures' localization accuracy was 0.52 ± 0.15 mm. The submillimetric accuracy of our system without tracker is compatible with ear surgery.

Minimally Invasive Cochlear Implantation Assisted by Intraoperative CT Scan Combined to Neuronavigation.

OBJECTIVE: The objective of this work was to study the feasibility of minimally invasive cochlear implantation under intraoperative computerized tomography-scan coupled to navigation. MATERIALS AND METHODS: Five human resin temporal bones (two adults and three children) were used. Initially, a temporal bone imaging was obtained by the intraoperative CT-scan coupled to the navigation (O-ARM). The navigation-assisted drilling began at the mastoid surface creating a conical tunnel (4-2 mm in diameter) through the facial recess and down to the round window. A cochleostomy was performed based on the navigation. A sham electrode array was inserted in the drilled tunnel and into the cochlea.Postoperative CT-scan and dissection were performed to evaluate the trajectory, and possible injury to the external auditory canal, ossicles, or facial nerve. RESULTS: The mean duration of the procedure was 24.4 ±â€Š3.79 minutes (range, 15-35). Cochleostomy was possible in all cases without injury to other structures. The sham array was inside the cochlea in all cases. The mean distance between the drilled canal and the mastoid portion of the facial nerve was 1.2 ±â€Š0.07 mm (range, 1.08-1.38). The mean tracking error was 0.6 ±â€Š0.26 mm (range, 0.20-0.72) at the entry point, 0.6 ±â€Š0.33 mm (range, 0.2-1.02) at the facial nerve and 0.4 ±â€Š0.07 mm (range, 0.36-0.51) at the cochleostomy. CONCLUSION: Cochlear implantation through a minimally invasive approach assisted by intraoperative imaging combined with navigation was feasible in operating room environment and experimental conditions.

Evaluation of the quality of the information received during head and neck cancer announcement: Prospective two-center study.

BACKGROUND: Providing patient with cancer with appropriate information following the disclosure of a cancer diagnosis has multiple benefits. The objective was to evaluate the quality of the information received during an announcement for head and neck cancer and to determine predictive factors. METHODS: We conducted a prospective two-center study using self-questionnaires to assess the patient's perception of the quality of the announcement. RESULTS: Satisfaction scores on the information provided about the overall disease were 7.7/10. The main positive predictors of quality were a satisfactory consultation setting (P = .004), assessment of pain by a physician (P = .04), physician availability (P = .003), accurate information about tumor stage, quality of information regarding the type (P < .0001) and purpose (P = .001) of treatment and its side effects (P = .006), and the interview with the oncology nurse coordinator (P < .05). CONCLUSIONS: Patients who received the announcement of head and neck cancer perceived the information received during the pretherapeutic period as satisfactory.

Contribution of Augmented Reality to Minimally Invasive Computer-Assisted Cranial Base Surgery.

Cranial base procedures involve manipulation of small, delicate and complex structures in the fields of otology, rhinology, neurosurgery and maxillofacial surgery. Critical nerves and blood vessels are in close proximity of these structures. Augmented reality is an emerging technology that can revolutionize the cranial base procedures by providing supplementary anatomical and navigational information unified on a single display. However, the awareness and acceptance of possibilities of augmented reality systems in cranial base domain is fairly low. This article aims at evaluating the usefulness of augmented reality systems in cranial base surgeries and highlights the challenges that current technology faces and their potential solutions. A technical perspective about different strategies employed in development of an augmented realty system is also presented. The current trend suggests an increase in interest towards augmented reality systems that may lead to safer and cost-effective procedures. However, several issues need to be addressed before it can be widely integrated into routine practice.