Predicting Matrix test effectiveness for evaluating auditory performance in noise using pure-tone audiometry and speech recognition in quiet in cochlear implant recipients.

INTRODUCTION: Auditory performance in noise of cochlear implant recipients can be assessed with the adaptive Matrix test (MT); however, when the speech-to-noise ratio (SNR) exceeds 15 dB, the background noise has any negative impact on the speech recognition. Here, we aim to evaluate the predictive power of aided pure-tone audiometry and speech recognition in quiet, and establish cut-off values for both tests that indicate whether auditory performance in noise can be assessed using the Matrix sentence test in a diffuse noise environment. METHODS: Here, we assessed the power of pure-tone audiometry and speech recognition in quiet to predict the response to the MT. Ninety-eight cochlear implant recipients were assessed using different sound processors from Advanced Bionics (n=56) and Cochlear (n=42). Auditory tests were performed at least 1-year after cochlear implantation or upgrading the sound processor to ensure the best benefit of the implant. Auditory assessment of the implanted ear in free-field conditions included: pure-tone average (PTA), speech discrimination score (SDS) in quiet at 65 dB, and speech recognition threshold (SRT) in noise that is the SNR at which the patient can correctly recognize 50% of the words using the MT in a diffuse sound field. RESULTS: The SRT in noise was determined in sixty patients (61%) and undetermined in 38 (39%) using the MT. When cut-off values for PTA <36 dB and SDS >41% were used separately, they were able to predict a positive response to the MT in 83% of recipients; using both cut-off values together, the predictive value reached 92%. DISCUSSION/CONCLUSION: As the pure-tone audiometry is standardized universally and the speech recognition in quiet could vary depending on the language used; we propose that the MT should be performed in recipients with PTA <36 dB, and in recipients with PTA >36 dB, a list of Matrix sentences at a fixed SNR should be presented to determine the percentage of words understood. This approach should enable clinicians to obtain information about auditory performance in noise whenever possible.

Long-term clinical and radiological results for fat graft obliteration in subtotal petrosectomy and cochlear implant surgery: a retrospective clinical study.

PURPOSE: The study aimed to evaluate the long-term clinical, radiological, and functional results for subtotal petrosectomy and cochlear implant surgery with closure of the external auditory canal and fat obliteration. METHODS: We retrospectively included all consecutive cases of simultaneous subtotal petrosectomy and cochlear implant surgery performed at a tertiary referral center between 2009 and 2016 using the same surgical technique. All patients underwent postoperative high-resolution computed tomography (HRCT) and annual audiological assessments. A 5-year minimum clinical, radiological, and audiological follow-up was performed. The early and late postoperative results were compared. The main outcome measures were complications, postauricular retraction, fat graft reabsorption, and audiological outcomes. RESULTS: Twenty-nine procedures performed in 23 patients (six bilateral) met the inclusion criteria. The mean age of the patients was 67 ± 13.4 years and mean follow-up duration was 7.5 ± 2 years. At follow-up, postauricular retraction was detected in 24 cases (82.8%), including five cases (17.1%) with subcutaneous protrusion of implant and array. Fat graft volume was significantly reduced at late-HRCT in terms of maximum diameter (2.24 ± 1.0 cm vs 3.69 ± 0.7 cm; p < 0.0005) and surface area (1.88 ± 1.2 vs 4.24 ± 1.6 cm2, p < 0.0005). Six patients had extracochlear electrodes at late-HRCT (3/6 had an increased number of extracochlear electrodes), with a lowering of this group's performance of - 15% (p < 0.005) in the follow-up speech comprehension test. CONCLUSIONS: Subtotal petrosectomy with cochlear implantation is an effective long-term technique in selected cases. Fat grafts showed significant reabsorption at long-term follow-up with reaeration of the middle ear spaces. Prolonged clinical and radiological follow-up is recommended for monitoring implant performances and late complications.

Auditory outcomes after scala vestibuli array insertion are similar to those after scala tympani insertion 1 year after cochlear implantation.

PURPOSE: In cochlear implantation, a scala vestibuli (SV) insertion of an electrode array is a rare occurrence and is reported to be linked to poor hearing outcomes. Using the same electrode array, the auditory performance of patients with a complete SV location was compared with that of patients having a complete scala tympani (ST) location 1 year after implantation. METHODS: Thirty-three patients were included in this retrospective case-control study (SV, n = 12; ST, n = 21). The matching criteria were electrode array type, age at implantation, and duration of severe or profound deafness. The array location was analyzed using 3D reconstruction of postoperative CT scans. Postoperative audiological evaluation of the implanted ear was performed using pure-tone audiometry, speech recognition of monosyllabic words in quiet, and words and sentences in noise. RESULTS: On the preoperative CT scan, six patients in the SV group presented with both round window (RW) and ST ossification, three with RW ossification alone, and three with no RW ossification. Auditory performance did not differ between SV and ST groups 1 year after cochlear implantation. Speech recognition of words was 49 ± 7.6% and 56 ± 5.0% in quiet and 75 ± 9.5% and 66 ± 6.0% in noise in SV and ST groups, respectively. CONCLUSION: ST insertion is the gold standard that allows the three cochlear scalae to preserve scalar cochlear integrity. However, 1 year after implantation, a planned or unexpected SV insertion is not detrimental to hearing outcomes, providing similar auditory performance in quiet and noise to ST insertion.

Simultaneous Bilateral Cochlear Implantation in Very Young Children Improves Adaptability and Social Skills: A Prospective Cohort Study.

OBJECTIVES: To investigate the value of using the Gesell Development Diagnosis Scale (GDDS) to predict developmental outcomes in very young children who undergo simultaneous bilateral cochlear implantation. DESIGN: In this prospective cohort study, a repeated-measures investigation was conducted in a tertiary referral hospital. A total of 62 children receiving simultaneous bilateral cochlear implantations were enrolled from April 2017 to August 2018. They were divided into 2 groups depending on the operative age: "Infants" group (6 to 12 months, N = 38) or "Children" group (12 to 36 months, N = 24). Data on the surgical outcomes, auditory development, speech production, and developmental indicators were collected until 2 years after the initial fitting. The primary outcome measure was the GDDS, a neuropsychological development examination. Secondary outcomes included the following: complication rate, aided pure-tone average, Infant-Toddler Meaningful Auditory Integration Scale, Categories of Auditory Performance-II, Meaningful Use of Speech Scale, Speech Intelligibility Rating, and the LittlEARS Auditory Questionnaire. RESULTS: The mean ages at implantation in infants and children groups were 9.2 ± 1.17 and 16.6 ± 3.60 months, respectively. Significant differences were found in the social skills ( p = 0.001) and adaptability ( p = 0.031) domains of GDDS. The younger the age of bilateral cochlear implants surgery, the higher developmental quotient of language, social skills, and adaptability the child could achieve after 2 years. The complication rates in the infants and children groups were 0% versus 2.1% ( p = 0.57). There was no surgical complication in the infants group. In the children group, 1 case with enlarged vestibular aqueduct and Mondini malformation had a receiver-implant misplacement on the right side (2%, 1/48). In the two groups, auditory performance and speech production had improved similarly. In the infants group, social skills developmental quotient at baseline had a significant positive relationship with Meaningful Use of Speech Scale after 2 years. CONCLUSIONS: Simultaneous bilateral cochlear implantation in younger children improves adaptability and social skills. GDDS is a sensitive tool of evaluating short-term effect of bilateral cochlear implants in neuropsychological development and constitutes a reliable predictor of speech production for the very younger pediatric cochlear implant users.

Atraumatic Insertion of a Cochlear Implant Pre-Curved Electrode Array by a Robot-Automated Alignment with the Coiling Direction of the Scala Tympani.

INTRODUCTION: Electrode array translocation is an unpredictable event with all types of arrays, even using a teleoperated robot in a clinical scenario. We aimed to compare the intracochlear trauma produced by the HiFocus™ Mid-Scala (MS) electrode array (Advanced Bionics, Valencia, CA, USA) using a teleoperated robot, with an automated robot connected to a navigation system to align the pre-curved tip of the electrode array with the coiling direction of the scala tympani (ST). METHODS: Fifteen freshly frozen temporal bones were implanted with the MS array using the RobOtol® (Collin, Bagneux, France). In the first group (n = 10), the robot was teleoperated to insert the electrode array into the basal turn of the ST under stereomicroscopic vision, and then the array was driven by a slow-speed hydraulic insertion technique with an estimated placement of the pre-curved electrode tip. In the second group (n = 5), 3 points were obtained from the preoperative cone-beam computed tomography: the 2 first defining the ST insertion axis of the basal turn and a third one at the center of the ST at 270°. They provided the information to the automated system (RobOtol® connected with a navigation system) to automatically align the electrode array with the ST insertion axis and to aim the pre-curved tip toward the subsequent coiling of the ST. After this, the electrode array was manually advanced. Finally, the cochleae were obtained and fixed in a crystal resin, and the position of each electrode was determined by a micro-grinding technique. RESULTS: In all cases, the electrode array was fully inserted into the cochlea and the depth of insertion was similar using both techniques. With the teleoperated robotic technique, translocations of the array were observed in 7/10 insertions (70%), but neither trauma nor array translocation occurred with automated robotic insertion. CONCLUSION: We have successfully tested an automated insertion system (robot + navigation) that could accurately align a pre-curved electrode array to the axis of the basal turn of the ST and its subsequent coiling, which reduced intracochlear insertion trauma and translocation.

Hearing recovery after surgical resection of non-vestibular schwannoma cerebellopontine angle tumors.

PURPOSE: Post-operative outcomes for hearing after resection surgery to remove cerebellopontine angle (CPA) tumors other than vestibular schwannomas (VS) are not well understood. This study presents a series of patients with significant post-operative hearing recovery, trying to define the incidence among all patients operated on for removal of non-VS CPA tumors. METHODS: This is a retrospective observational case series of 8 patients among 69 operated on for removal of non-VS CPA tumors between 2012 and 2020. All patients had pre- and post-operative hearing measurement with pure-tone average (PTA) and speech discrimination score (SDS), according to the American Academy of Otolaryngology-Head and Neck Surgery recommendations, auditory brainstem response (ABR) measurements and imaging. RESULTS: Six meningiomas and two lower cranial nerve schwannomas operated on with a retrosigmoid approach were included for analysis. The mean pre-operative PTA and SDS were 58 ± 20.7 dB and 13 ± 17.5%, respectively. All patients had pre-operative class D hearing and asynchronous ABRs. They all showed significant hearing recovery, with an improvement of 36 ± 22.2 dB (p = 0.0025) and 85 ± 16.9% (p = 0.0001) in PTA and SDS, respectively, with mean follow-up of 21 ± 23.5 months. Seven patients recovered to a class A hearing level and one patient to class B. The ABRs became synchronous for three patients. The incidence of auditory recovery was 13% for patients operated on with a conservative approach (n = 60). CONCLUSION: A significant post-operative improvement in hearing could be a reasonable expectation in non-VS tumors extending into the CPA and a retrosigmoid approach should always be considered regardless of pre-operative hearing status.

Cochlear Implantation and Other Treatments in Single-Sided Deafness and Asymmetric Hearing Loss: Results of a National Multicenter Study Including a Randomized Controlled Trial.

INTRODUCTION: Cochlear implantation is a recent approach proposed to treat single-sided deafness (SSD) and asymmetric hearing loss (AHL). Several cohort studies showed its effectiveness on tinnitus and variable results on binaural hearing. The main objective of this study is to assess the outcomes of cochlear implantation and other treatment options in SSD/AHL on quality of life. METHODS: This prospective multicenter study was conducted in 7 tertiary university hospitals and included an observational cohort study of SSD/AHL adult patients treated using contralateral routing of the signal (CROS) hearing aids or bone-anchored hearing systems (BAHSs) or who declined all treatments, and a randomized controlled trial in subjects treated by cochlear implantation, after failure of CROS and BAHS trials. In total, 155 subjects with SSD or AHL, with or without associated tinnitus, were enrolled. After 2 consecutive trials with CROS hearing aids and BAHSs on headband, all subjects chose any of the 4 treatment options (abstention, CROS, BAHS, or cochlear implant [CI]). The subjects who opted for a CI were randomized between 2 arms (CI vs. initial observation). Six months after the treatment choice, quality of life was assessed using both generic (EuroQoL-5D, EQ-5D) and auditory-specific quality-of-life indices (Nijmegen Cochlear implant Questionnaire [NCIQ] and Visual Analogue Scale [VAS] for tinnitus severity). Performances for speech-in-noise recognition and localization were measured as secondary outcomes. RESULTS: CROS was chosen by 75 subjects, while 51 opted for cochlear implantation, 18 for BAHSs, and 11 for abstention. Six months after treatment, both EQ-5D VAS and auditory-specific quality-of-life indices were significantly better in the "CI" arm versus "observation" arm. The mean effect of the CI was particularly significant in subjects with associated severe tinnitus (mean improvement of 20.7 points ± 19.7 on EQ-5D VAS, 20.4 ± 12.4 on NCIQ, and 51.4 ± 35.4 on tinnitus). No significant effect of the CI was found on binaural hearing results. Before/after comparisons showed that the CROS and BAHS also improved significantly NCIQ scores (for CROS: +7.7, 95% confidence interval [95% CI] = [4.5; 10.8]; for the BAHS: +14.3, 95% CI = [7.9; 20.7]). CONCLUSION: Cochlear implantation leads to significant improvements in quality of life in SSD and AHL patients, particularly in subjects with associated severe tinnitus, who are thereby the best candidates to an extension of CI indications.

Objective improvement in adults with cerebellopontine angle arachnoid cysts after surgical treatment.

BACKGROUND: Intracranial arachnoid cysts are extra-axial benign lesions mainly found in the middle cerebral fossa. Rare case series report various cranial nerve dysfunctions associated with cerebellopontine angle (CPA) cysts and there is no consensus with regard to their surgical management; some reports claiming that subjective improvement in adults with intracranial arachnoid cysts cannot justify surgical treatment. METHODS: This retrospective study included all 12 consecutive adult patients treated by microsurgical fenestration for symptomatic CPA arachnoid cysts between 2010 and 2019 and using a retrosigmoid approach. Demographic, clinical, surgical, and radiological data were collected from medical files. RESULTS: The main symptoms were audiovestibular in 9 patients (75%) complaining of dizziness and 6 patients (50%) with hearing loss. In addition, 3 patients (25%) reported tinnitus, 3 patients (25%) presented vasovagal syncope, and 1 patient (8.3%) reported facial pain. Surgery improved 5 patients (83%) with pre-operative hearing loss, 7 patients (78%) reporting dizziness, and all patients with vasovagal syncope. All of the patients recovered from at least one symptom. No recurrence was observed with a mean follow-up of 5.5 years. CONCLUSION: Although most arachnoid cysts are asymptomatic, the CPA location may lead to cranial nerve impairments. Microsurgical fenestration seems to be a simple, safe, and effective technique.

Intraoperative facial nerve electromyography parameters to optimize postoperative facial nerve outcome in patients with large unilateral vestibular schwannoma.

BACKGROUND: Decision-making for large sporadic vestibular schwannomas (VS) resection guided by the intraoperative change in supramaximal facial nerve (FN) amplitude and latency response to optimize post-operative FN outcome. METHODS: Prospectively study of 43 patients, from January to December 2018, of large sporadic VS with preoperative normal FN function at our center. Tumors were removed through retrosigmoid (81%) or translabyrinthine (19%) approaches with FN monitoring. Intraoperative pre- and post-VS resection supramaximal (2 mA) amplitude and latency responses at the proximal FN root were recorded. RESULTS: Total, near-/subtotal VS resections (TR, NTR, STR) were achieved in 51%, 38%, and 11% of tumors, respectively, guided by no more than 40% decrease in supramaximal amplitude. Pre- and post-resection supramaximal amplitude and latency responses were lower and longer, respectively, in NTR+STR than in TR. At day 8, FN function was grade I-II in 77% of patients and grade III-V in 23%, and after 6 months, it was in grade I-II in 95% and grade III in 5%, and there was no significant difference between TR and NTR+STR. Facial palsy occurred in older patients and in the case of severe FN adhesion. At day 8, pre- and post-resection supramaximal amplitude but not latency responses were different between FN grade III-V and grade I-II. Serviceable hearing was preserved in 28% of large VS. CONCLUSIONS: Intraoperative FN monitoring guided VS resection in large VS so that 49% retained some residual tumor. Accordingly, 95% good postoperative FN function and significant hearing preservation were achieved after 6 months.

Benefits in noise from sound processor upgrade in thirty-three cochlear implant users for more than 20 years.

PURPOSE: Some oldest patients rehabilitated with a cochlear implant more than 20 years ago could still be upgraded with new generations of speech processor (SP). The aim of this study was to show the benefit of a recent generation of SP in this population. METHODS: A monocentric prospective study was designed to evaluate the performance of 33 ancient CI22M users implanted between 1989 and 1997 and upgraded with the late compatible sound processor CP900. Performance was evaluated in quiet and noise with Framatix, an automated adaptative test. RESULTS: Performance using Framatix significantly improved with the CP900, with a decrease of the median speech perception threshold of 6 dB in quiet (p < 0.05) and 5,3 dB in noise (p < 0.0005). No subjective benefit using the APHAB questionnaire was observed. CONCLUSION: Upgrading of cochlear implant recipients who were implanted more than 20 years ago with recent compatible and new technological SP provide benefit in speech recognition in noise.

Analysis of forces during robot-assisted and manual manipulations of mobile and fixed footplate in temporal bone specimens.

PURPOSE: To evaluate the forces involved in different manipulations, manual or robot-assisted, applied to the ossicular chain, on normal temporal bones and on an anatomical model of otosclerosis. METHODS: Thirteen cadaveric temporal bones, with mobile footplates or with footplates that were fixed using hydroxyapatite cement, were manipulated, manually or using a robotic arm (RobOtol®). "Short contact" of a mobile footplate was the weakest interaction on the incus. "Long contact" was the same manipulation held for 10 s. "Mobilization" was the smallest visualized movement of the mobile footplate, or the movement necessary to regain mobility of the fixed footplate. A six-axis force sensor (Nano17, ATI) measured the maximal peak of forces, summation of forces applied, and yank. RESULTS: Maximal forces during short (~4 mN) and long contact (~15 mN) were similar for manual and robot-assisted manipulations. For manual manipulation, yank measured during long contact was twice as high compared to robot-assisted manipulation: 6 ± 2.4 (n = 5) and 3 ± 1.3 mN/s (n = 5), respectively (mean ± SD, p < 0.02). For mobilization of the mobile footplate, maximal forces during mobilization were similar during manual and robot-assisted manipulations, respectively: 12 ± 2.5 (n = 6) and 19 ± 7.6 mN (n = 7). Compared with mobilization of a mobile footplate, mobilization of a fixed footplate required ~ 60 and ~ 27 times higher maximal forces for manual and robot-assisted manipulations, respectively: 724 ± 366.4 and 507 ± 283.2 mN. Yank was twice as high during manual manipulation compared to robot-assisted manipulation (p < 0.05). CONCLUSION: Robot-assisted manipulation of the ossicular chain was reliable. Our anatomical model of otosclerosis was successfully developed requiring higher forces for stapes mobilization.

Robot-based assistance in middle ear surgery and cochlear implantation: first clinical report.

PURPOSE: Middle ear surgery may benefit from robot-based assistance to hold micro-instruments or an endoscope. However, the surgical gesture performed by one hand may perturb surgeons accustomed to two-handed surgery. A robot-based holder may combine the benefits from endoscopic exposure and a two-handed technique. Furthermore, tremor suppression and accurate tool control might help the surgeon during critical surgical steps. The goal of this work was to study the safety of an otological robot-based assistant under clinical conditions in a limited series of patients. METHODS: The RobOtol system has been used as an endoscope or a micro instrument holder for this series. Eleven cases were operated on with the robot as an endoscope holder for chronic otitis. Twenty-one cases were operated on with the robot as a micro-instrument holder for otosclerosis (9 cases), transtympanic tube placement (2 cases), or cochlear implantation (10 cases). RESULTS: No complications related to the robot manipulation occurred during surgery nor in postoperative. In the chronic otitis group, all perforations were sealed and 3-month postoperative pure-tone average air-bone gap (PTA ABG) was 15 ± 2.6 dB. In the otosclerosis group, 1-month post-op PTA ABG was 10 ± 1 dB. For cochlear implantation cases, a scala tympani insertion, a vestibular scala translocation occurred and a full scala vestibuli insertion was observed in 7, 2 and 1 case, respectively. CONCLUSION: The RobOtol system has reached the clinical stage. It could be used safely and with accurate control as an endoscope holder or a micro instrument holder in 32 cases.

Treatment choice in single-sided deafness and asymmetric hearing loss. A prospective, multicentre cohort study on 155 patients.

OBJECTIVES: To describe the treatment choice in a cohort of subjects with single-sided deafness (SSD) and asymmetric hearing loss (AHL). To assess the reliability of the treatment trials. DESIGN: In this national, multicentre, prospective study, the choice of subjects was made after two consecutive trials of Contralateral Routing Of the Signal (CROS) hearing aids and a Bone Conduction Device (BCD) on a headband. Subjects could proceed with one of these two options, opt for cochlear implantation or decline all treatments. SETTING: Seven tertiary university hospitals. PARTICIPANTS: One hundred fifty-five subjects with SSD or AHL fulfilling the candidacy criteria for cochlear implantation, with or without associated tinnitus. MAIN OUTCOME MEASURES: After the two trials, the number of subjects choosing each option was described. Repeated assessments of both generic and auditory-specific quality of life were conducted, as well as hearing assessments (speech recognition in noise and horizontal localization). RESULTS: CROS was chosen by 75 subjects, followed by cochlear implantation (n = 51), BCD (n = 18) and abstention (n = 11). Patients who opted for cochlear implantation had a poorer quality of life (P = .03). The improvement of quality of life indices after each trial was significantly associated with the final treatment choice (P = .008 for generic indices, P = .002 for auditory-specific indices). The follow-up showed that this improvement had been overestimated in the CROS group, with a long-term retention rate of 52.5%. CONCLUSIONS: More than one third of SSD/AHL subjects are unsatisfied after CROS and BCD trials. Repeated quality of life assessments help counselling the patient for his/her treatment choice.

FDXR Mutations Cause Sensorial Neuropathies and Expand the Spectrum of Mitochondrial Fe-S-Synthesis Diseases.

Hearing loss and visual impairment in childhood have mostly genetic origins, some of them being related to sensorial neuronal defects. Here, we report on eight subjects from four independent families affected by auditory neuropathy and optic atrophy. Whole-exome sequencing revealed biallelic mutations in FDXR in affected subjects of each family. FDXR encodes the mitochondrial ferredoxin reductase, the sole human ferredoxin reductase implicated in the biosynthesis of iron-sulfur clusters (ISCs) and in heme formation. ISC proteins are involved in enzymatic catalysis, gene expression, and DNA replication and repair. We observed deregulated iron homeostasis in FDXR mutant fibroblasts and indirect evidence of mitochondrial iron overload. Functional complementation in a yeast strain in which ARH1, the human FDXR ortholog, was deleted established the pathogenicity of these mutations. These data highlight the wide clinical heterogeneity of mitochondrial disorders related to ISC synthesis.

Improving facial nerve outcome and hearing preservation by different degrees of vestibular schwannoma resection guided by intraoperative facial nerve electromyography.

BACKGROUND: Facial nerve (FN) outcome has been improved by deciding upon the degree of vestibular schwannoma (VS) resection guided by intraoperative facial nerve monitoring (IOFM). This study aimed to evaluate hearing and FN outcomes following IOFM-guided VS removal through a retrosigmoid approach (RS). METHODS: Between January 2015 and August 2017, 77 patients undergoing VS resection through RS, regardless of their preoperative hearing or tumor size, were included in this monocentric retrospective study. Total or near-/subtotal resection was decided intraoperatively according to IOFM. Partial resection was planned preoperatively. Pre- and postoperative FN function (House-Brackmann) and hearing level (AAO-HNS and Gardner-Robertson (GR) scales) were reported. Predictive factors for hearing preservation were analyzed according to a score developed to take into account pre-/postoperative hearing evolution. RESULTS: The mean extrameatal diameter was 17 ± 8.5 mm. VS resection was total, near-/subtotal, and partial in 71%, 21%, and 8% of cases, respectively. Postoperative grade I and II FN function was achieved in 91% of patients. Serviceable (A+B or GR I+II) hearing and hearing with intelligibility (A+B+C or GR I-III) were preserved in 30% and 43% of cases, respectively. In multivariate analysis, preoperative synchronized auditory brainstem responses (ABR) were the only predictive factor (p = 0.006) imparting a five times greater chance of hearing preservation. CONCLUSION: IOFM-guided VS excision through RS, whatever the VS size and hearing level, achieved a high rate of good postoperative FN function together with significant hearing preservation, and it should be used if hearing with some intelligibility is still present preoperatively, even in large VS.

Long-term residual hearing in cochlear implanted adult patients who were candidates for electro-acoustic stimulation.

PURPOSE: To evaluate the long-term hearing outcomes in cochlear implanted adults with residual hearing at low frequencies, and the proportion of patients using electro-acoustic stimulation (EAS). METHODS: A monocentric retrospective cohort study was performed in a tertiary referral center. Population demographics, surgical approach, pre- and postoperative hearing at low frequencies, in the implanted and contralateral ear, were recorded as well as duration of EAS use. The percentage hearing preservation was calculated according to the formula S (HEARRING group). RESULTS: In total, 63 adults (81 ears) with residual hearing underwent cochlear implantation with intent to use EAS processors. Six different types of electrode array were implanted. The mean pure tone audiometry (PTA) shift after cochlear implantation was 16 ± 15 dB HL (range 0-59 dB HL). Half of the implanted ears had minimal hearing preservation or total hearing loss (HL) at 5.5 years and the cumulative risk of total HL was 50% at 7 years. During the follow-up, total HL occurred in 22 ears. The decrease in hearing levels was similar in both implanted and contralateral ear during follow-up (ns, F = 2.46 ± 3, Linear Mixed Model (LMM)). Only 44 patients found a benefit from EAS at the first fitting. At the last visit, EAS processors were fitted in 30% of the cases. The pre- and postoperative mean PTA thresholds were not predictive of EAS use (Cox's proportional hazards analysis). CONCLUSIONS: Postoperative residual hearing was observed in 93% of implanted ears, but only half of them had an initial benefit from EAS. No predictive factors were found to influence the use of EAS processors.

Bioactive glass granules for mastoid and epitympanic surgical obliteration: CT and MRI appearance.

PURPOSE: To evaluate the appearance of mastoid and epitympanic obliteration using S53P4 bioactive glass (BG) granules in high-resolution computed tomography (HRCT) and MRI. MATERIALS AND METHODS: Patients undergoing mastoid and epitympanic obliteration between May 2013 and December 2015 were prospectively included in an uncontrolled clinical study. All patients underwent a temporal HRCT scan 1 year after surgery, aimed at evaluating the attenuation, homogeneity, and osseointegration of the BG granules, as well as the ventilation of the middle ear and the volume of the obliterated paratympanic spaces. If a cholesteatoma was found during surgery, additional MRI, including at least pre- and post-contrast T1-weighted, T2-weighted, and axial non-echo-planar diffusion-weighted (DW) sequences, was performed 1 year after surgery, to study the normal signal of the BG granules and the presence of residual cholesteatoma and/or other temporal bone pathologies. RESULTS: Seventy cases were included. On 1-year HRCT, the mean attenuation of the BG granules was 888.34 ± 166.10 HU. The obliteration was found to be mostly homogeneous with partial osseointegration. The appearance of the BG granules having a low-intensity signal in T2-weighted imaging and DW MRI was always different from the appearance of cholesteatoma. A longer follow-up has shown no attenuation or signal modification of the BG granules compared with the 1-year imaging. CONCLUSION: Radiological follow-up of patients operated on with mastoid and epitympanic obliteration using BG granules is effective using both HRCT and MRI. A cholesteatoma and/or other potential complications could easily be detected due to the specific radiological appearance of the BG granules. KEY POINTS: • The appearance of mastoid and epitympanic obliteration by S53P4 bioactive glass (BG) granules on high-resolution computed tomography (HRCT) scans was homogeneous with an attenuation significantly higher than the attenuation of cholesteatoma and lower than mastoid bone attenuation. • The granules have a low-intensity signal on non-echo-planar diffusion-weighted sequences and on T2-weighted images and present contrast enhancement allowing the differential diagnosis with cholesteatoma and effective for the detection of other underlying temporal bone pathologies. • The volume and radiological appearance of the obliteration appear to be stable with time.

Benefits of a contralateral routing of signal device for unilateral Naída CI cochlear implant recipients.

PURPOSE: Many bilaterally deaf adults are only able to receive one cochlear implant (CI), resulting in suboptimal listening performance, especially in challenging listening environments. Adding a contralateral routing of signal (CROS) device to a unilateral CI is one possibility to alleviate these challenges. This study examined the benefit of such a CROS device. METHODS: Thirteen adult subjects with at least 6 months of CI use, and no or limited benefit of a hearing instrument in the contralateral ear were included in the study. The perceived benefit of a CROS device in everyday listening environments was evaluated up to 1 year after initial fitting using several questionnaires. Speech intelligibility performance was determined using the French matrix sentence test in quiet and in two speech-in-noise setups and was followed for 3 months after CROS fitting. RESULTS: Subjects indicated high satisfaction with the practical usability of the CROS device and long-term device retention was high. Perceived benefits in everyday listening environments were reported. Formal speech intelligibility tests revealed statistically significant median improvements of 6.93 dB SPL (Wilcoxon Z = 2.380, p = 0.017) in quiet and up to 8.00 dB SNR (Wilcoxon Z = 2.366, p = 0.018) in noise. These benefits were accessible immediately without a need for prolonged acclimatization. CONCLUSIONS: Subjective satisfaction and device retention as well as speech intelligibility benefits in quiet and in noise prove the CROS device to be a valuable addition to a unilateral CI in cases of bilateral deafness where bilateral implantation is not an option.

3D endoscopic ear surgery: a clinical pilot study.

OBJECTIVE: To evaluate the feasibility and efficacy of a new high-resolution 3D endoscope in endoscopic ear and lateral skull base surgery. METHODS: Eight patients, five women and three men, were included in this clinical pilot prospective study. Their age was 38 ± 17.3 years (mean ± SD, range 17-54 years). The right side was involved in five cases, and the left side in three cases. There were three cases of chronic otitis, one case of cholesteatoma of the external auditory canal, one case of otosclerosis, one case of cochlear implant surgery, and two cases of stage 2 vestibular schwannoma operated on with a retrosigmoid approach to preserve hearing. RESULTS: There were no intraoperative or postoperative complications. The new system was used during all procedures without the necessity to switch to a 2D mode. The surgeons felt comfortable using the system and its major advantages were considered to be in measuring the distances for ossicular chain reconstruction and in the sense of depth provided in the middle ear and cerebellopontine angle. CONCLUSION: The sense of depth provided by the 3D system is effective in both middle ear and lateral skull base surgery. Further improvements (smaller and/or more angled endoscopes) should be considered for future developments in endoscopic ear surgery.

Improvement of the insertion axis for cochlear implantation with a robot-based system.

It has previously reported that alignment of the insertion axis along the basal turn of the cochlea was depending on surgeon' experience. In this experimental study, we assessed technological assistances, such as navigation or a robot-based system, to improve the insertion axis during cochlear implantation. A preoperative cone beam CT and a mastoidectomy with a posterior tympanotomy were performed on four temporal bones. The optimal insertion axis was defined as the closest axis to the scala tympani centerline avoiding the facial nerve. A neuronavigation system, a robot assistance prototype, and software allowing a semi-automated alignment of the robot were used to align an insertion tool with an optimal insertion axis. Four procedures were performed and repeated three times in each temporal bone: manual, manual navigation-assisted, robot-based navigation-assisted, and robot-based semi-automated. The angle between the optimal and the insertion tool axis was measured in the four procedures. The error was 8.3° ± 2.82° for the manual procedure (n = 24), 8.6° ± 2.83° for the manual navigation-assisted procedure (n = 24), 5.4° ± 3.91° for the robot-based navigation-assisted procedure (n = 24), and 3.4° ± 1.56° for the robot-based semi-automated procedure (n = 12). A higher accuracy was observed with the semi-automated robot-based technique than manual and manual navigation-assisted (p < 0.01). Combination of a navigation system and a manual insertion does not improve the alignment accuracy due to the lack of friendly user interface. On the contrary, a semi-automated robot-based system reduces both the error and the variability of the alignment with a defined optimal axis.