Advances in the management of NF2-related schwannomatosis (NF2-SWN) have improved survival, but long-term complications such as increased intracranial pressure (IICP) remain insufficiently characterized. This study investigated the mechanisms, clinical presentation, and prognostic impact of IICP in NF2-SWN. We conducted a bicentric retrospective study including 551 NF2-SWN patients followed between 1994 and 2026 in two national reference centers. IICP was defined using combined clinical, ophthalmological, and radiological criteria, including papilledema. Mechanisms were categorized into hydrocephalus, tumor-related mass effect, and venous outflow obstruction. Volumetric analyses were performed using 3D segmentation to calculate tumor volumes and annual growth rates. Clinical manifestations of IICP were also compared according to history of posterior fossa vestibular schwannoma surgery. Thirty-three patients (6.0

Objective The aim of this study is to detail and evaluate the surgical procedure for perilymph sampling from the cochlear apex in the Mongolian gerbil. Design Perilymph sampling from the cochlear apex was performed one to three time in 12 male gerbils aged 8 to 12 months via the submandibular route. 11 of them were previously implanted with intracochlear implants loaded with dexamethasone and placed in the scala tympani, the 12th was used to collect control samples. The procedure was performed under general gas anesthesia, with head support, by a submandibular approach. After opening the bulla and sacrificing the external and middle ears, the cochlea was exposed and perilymph sampled. Macroscopic features of perilymph samples were reported before an HPLC-MS/MS assay to detect and quantify dexamethasone. Some cochleae were then harvested, immunostained and cleared to study fibrosis formation along the labyrinth and evaluate the consequences of multiple sampling procedures. Results The perilymph sampling procedure was technically difficult and required experimenter training. The procedure was well tolerated by the animals. One drawback of this technique in our gerbil model was the need to sacrifice the external ear, eardrum and ossicular chain to allow sufficient exposure for a quality procedure. Our technique enabled the collection of perilymph samples of the desired volume. Most of our samples were contaminated by bleeding from the otic capsule bone secondary to the cochleostomy. Nevertheless, HPLC-MS/MS analyses which successfully found dexamethasone in the perilymph of implanted gerbils, confirmed that our method was suitable for pharmacokinetic analyses. The occurrence of areas of fibrosis in the labyrinth after a sampling procedure compromises the quality and reliability of subsequent samples from the same animal. Conclusion The Mongolian gerbil is an animal model that can be used to collect perilymph from the cochlear apex to perform pharmacokinetic studies. The number of samples taken from a single animal must be limited to one.

INTRODUCTION:Assessing cochlear implantation's impact on cell loss and preventing post-implant cochlear damage are key areas of focus for hearing preservation research. The preservation of auditory neuronal and sensory neural hearing cells has a positive impact on auditory perception after implantation. This study aimed to provide details on a semi-automated spiral ganglion neuronal cell counting method, developed using whole implanted gerbil cochlea acquisitions with light-sheet microscopy. METHODS:Mongolian gerbils underwent right cochlear implantation with an electrode array whose silicone was loaded with dexamethasone or not and were euthanized 10 weeks after implantation. The cochleae were prepared according to a 29-day protocol, with the electrode array in place. Light-sheet microscopy was used for acquisition, and Imaris software was employed for three-dimensional analysis of the cochleas and semi-automatic quantification of spiral ganglion cells. The imaJ software was used for the manual quantification of these cells. RESULTS:Six cochleae were acquired by light-sheet microscopy, allowing good identification of cells. There was no significant difference between the mean number of spiral ganglion cells obtained by manual and semi-automatic counting (p = 0.25). CONCLUSION:Light-sheet microscopy provided complete visualization of the spiral ganglion and cell identification. The semi-automated counting method developed using Imaris software tools proved reliable and efficient and could be applied to a larger sample to assess post-cochlear implant cell damage and the efficacy of protective drugs delivered to the inner ear.

Background: The objective of this study was to describe the long-term hearing outcomes of gamma knife treatment for unilateral progressing vestibular schwannomas (VS) presenting with good initial hearing using audiologic data. Methods: A retrospective review was performed between 2010 and 2020 to select patients with progressing unilateral VS and good hearing (AAO-HNS class A) treated with stereotactic gamma knife surgery (GKS). Their audiograms were analyzed along with treatment metrics and patient data. Results: Hearing outcomes with a median follow-up of 5 years post-treatment showed statistically significant loss of serviceable hearing: 34.1% of patients maintained good hearing (AAO-HNS class A), and 56.1% maintained serviceable hearing (AAO-HNS class A and B). Non-hearing outcomes are favorable with excellent tumor control and low facial nerve morbidity. Conclusions: Hearing declines over time in intracanalicular VS treated with GKS, with a significant loss of serviceable hearing after 5 years. The mean cochlear dose and the presence of cochlear aperture obliteration by the tumor are the main statistically significant factors involved in the hearing outcomes.

This report discusses 2 clinical cases where the failure of osseointegration in bone-anchored implants may be associated with their placement directly in cranial sutures. The increasing shift toward minimally invasive surgical techniques for implant placement, such as the minimally invasive Ponto surgery (MIPS) and the punch technique, raises concerns about the risk of inadvertently positioning implants on cranial sutures, which can lead to the failure of osseointegration. In the first case, the Ponto (Oticon) implant and abutment were placed using MIPS. Two months post-operation, minimal movement was observed until the implant was significantly displaced, necessitating its removal. A subsequent computed tomography (CT) scan revealed that the implant had been placed in the asterion. The second case involved a Bone Anchored Hearing Aid (BAHA-Cochlear) implant and abutment inserted via a punch and drill technique. Early mobilization of the abutment was observed, progressively worsening until the implant was removed 2 months post-operation. A CT scan showed that the implant was located at the parietooccipital suture. These cases highlight a potential complication of minimally invasive implant surgery, suggesting that blind placement could elevate the risk of implant failure due to interference with cranial sutures. This underscores the importance of enhancing surgical precision and pre-operative planning with imaging.

PURPOSE:To corroborate the vascular etiology of sudden sensorineural hearing loss (SNHL) utilizing magnetic resonance imaging (MRI). PATIENT:A 24-year-old male with a history of sickle cell disease experienced sudden SNHL and right horizontal nystagmus, without accompanying vertigo. INTERVENTION:Audiometric evaluation revealed left-sided SNHL, predominantly affecting high frequencies. Video head impulse testing demonstrated isolated dysfunction of the left posterior semicircular canal. An urgent brain MRI identified a recent punctiform ischemic stroke in the frontal region. A subsequent MRI, conducted with a 4-hour delay and post-contrast enhancement, highlighted a hyperintense signal within the left cochlear region and the left posterior semicircular canal. CONCLUSION:The investigative results substantiate an infarction in the territory of the cochlear artery, precipitated by a vaso-occlusive event, thereby reinforcing the vascular hypothesis of cochleovestibular artery syndrome. This case underscores the congruence between clinical observations and delayed post-contrast MRI findings.

Objective The cochlear implant is a commonly used implantable device for the auditory rehabilitation of severe bilateral sensorineural hearing loss. The effectiveness of the implant, depends on many factors, including intensive auditory training, which is crucial. Intelligibility in a noisy environment is a current issue and poses a major difficulty for implanted patients. The aim of this study is to evaluate the improvement in auditory performance in noise among cochlear implant patients who underwent personalized auditory-cognitive training for speech understanding tasks in noise. Design This was a prospective study involving cochlear implanted patients divided into two groups. One group underwent auditory training in a noisy environment at home for 2 months (G1) while the other group served as a control (G0). A test of intelligibility performance in noise was conducted at inclusion and two months later. Results 52 patients were included in the study. The trained group, G1, showed a significant improvement with an increase of 4.8 dB in signal-to-noise ratio (SNR) between the two tests (P < 0.01). There was no significant improvement in the control group (G0) (P = 0.756). Conclusions This study demonstrated a significantly positive impact of personalized auditory training in a noisy environment for cochlear implant patients.

Risoud, Michaël; Toulemonde, Philippine; Beck, Cyril; Schapira, Stéphane; Vincent, Christophe Author Information

Cochlear implant is the method of choice for the rehabilitation of severe to profound sensorineural hearing loss. The study of the tissue response to cochlear implantation and the prevention of post-cochlear-implant damages are areas of interest in hearing protection research. The objective was to assess the efficacy of dexamethasone-eluting electrode array on endo canal fibrosis formation by three-dimensional immunofluorescence analysis in implanted Mongolian gerbil cochlea. Two trials were conducted after surgery using Mongolian gerbil implanted with dexamethasone-eluting or non-eluting intracochlear electrode arrays. The animals were then euthanised 10 weeks after implantation. The cochleae were prepared (electrode array in place) according to a 29-day protocol with immunofluorescent labelling and tissue clearing. The acquisition was carried out using light-sheet microscopy. Imaris software was then used for three-dimensional analysis of the cochleae and quantification of the fibrotic volume. The analysis of 12 cochleae showed a significantly different mean volume of fibrosis (2.16 × 108 μm3 ± 0.15 in the dexamethasone eluting group versus 3.17 × 108 μm3 ± 0.54 in the non-eluting group) (p = 0.004). The cochlear implant used as a corticosteroid delivery system appears to be an encouraging device for the protection of the inner ear against fibrosis induced by implantation. Three-dimensional analysis of the cochlea by light-sheet microscopy was suitable for studying post-implantation tissue damage.

The aim of this study is to assess the diagnostic performance of a new MR sign, named the round window sign (RWS), to diagnose perilymphatic fistula (PLF) in a population of patients with chronic cochleo-vestibular symptoms, classified as definite or probable Menière’s disease (MD). A total of 164 patients (mean age 52 ± 35 years) with chronic cochleo-vestibular symptoms underwent MRI, between 4 and 5 h after intravenous gadoteric acid injection (Dotarem®, 0.1 mmol/kg). MRI exploration was carried out on a 3-T Achieva® TX scanner. We analyzed the presence of the RWS, defined as a nodular FLAIR high signal in the round window (RW) and the presence of associated saccular hydrops. When this RWS was present, a temporal bone CT scan was performed and the RW was analyzed. Of the 164 patients with definite MD (85 patients) or probable MD (79 patients), we found the RWS in 18 (11%), and 17/18 were classified into the group of probable MD. All these 18 patients showed other MR sequences considered as normal, including heavily weighted T2 imaging. Among these 18 patients, the temporal bone CT examination presented a filling of the RW in 13 patients (72%) and no filling of the RW in 5 patients (28%). Seven patients were surgically managed confirming in vivo the PLF diagnosis. The RWS was associated with the presence of a saccular hydrops in 4 cases. Delayed postcontrast 3D-FLAIR may reveal perilymphatic fistulae in patients with probable Menière’s disease using the round window sign. • MRI with delayed acquisition can detect perilymphatic fistulae with perfect sensitivity, based on the presence of the round window sign. • This visual sign is only visible on a 3D-FLAIR sequence. • 3D-FLAIR sequence with delayed acquisition is more sensitive than temporal bone CT scan examination in detecting PLF.

To perform a long-term evaluation of the localisation capabilities in the horizontal plane of single-sided deaf patients fitted with a BAHA device.Single-centre retrospective study.Twenty-one adults with single-sided deafness (SSD) with normal hearing in the contralateral ear (pure tone average <20 dB, SDS > 90%) rehabilitated with a Cochlear BAHA device from 2003 to 2012 on the deaf side over a median follow-up of 8 years.The task used in this paper is a sound localisation identification task with a set-up of seven loudspeakers on a semi-circular array at 30-degree intervals performed at three periods: before BAHA, initially and at last follow-up. Our main criterion of judgement was the root-mean-square (RMS) localisation error. In addition, the Bern Benefit in Single-Sided Deafness Questionnaire (BBSS) was administered.The mean RMS localisation error was initially estimated at 64° without any rehabilitation (for a chance level RMS estimated at 81°). Initially, with the BAHA device, the RMS localisation error dropped to 51°. At the last follow-up evaluation, a significant decrease at 23° was noted. Concerning the Bern Questionnaire, 19% of the patients (n = 4) did not report any change (score of 0), 33% (n = 7) are satisfied (score of +1 or +2) and 48% (n = 10) are very satisfied with the BAHA device (score better than +3).Improvement of sound localisation in the horizontal plane for some SSD patients is likely related to altered processing of monaural spectral cues. The time needed to learn to use the azimuth-dependent spectral cues takes time. Long-term follow-up should be considered for studies investigating sound localisation performance.

BACKGROUND:Hearing response following an osteodural decompression of the internal auditory canal (IAC) is controversial. OBJECTIVE:To evaluate the course of auditory brainstem responses (ABRs) and the early hearing response during the first year following IAC decompression for small to medium-sized vestibular schwannomas occurring in neurofibromatosis type 2 (NF2). METHODS:Retrospective chart review of middle fossa craniotomy for IAC osteodural decompression in NF2-related vestibular schwannomas. RESULTS:Twelve NF2 patients were operated on from 2011 to 2016 for IAC decompression. All had NF2 according to the Manchester criteria. All had a progressive change of their ABRs documented from the diagnosis of NF2 over a mean period of 6.25 [0.36;10.9] yr. Treatment was proposed to stop hearing progression based on the speech discrimination scores (SDSs; n = 4) or for hearing maintenance (n = 8). In patients with prior hearing progression, hearing responses were observed in 3 of the 4 patients during the first year. One patient kept on progressing. In the hearing maintenance group, the SDSs remained stable. SDSs improved from 85% [20-100] to 92.5% [60-100] on average (n = 12) and from 55% [20-80] to 77.5% [50-100] in the hearing progression group (n = 4). ABRs improved in 4 patients following decompression. CONCLUSION:IAC decompression allows early objective hearing responses in select patients. We suggest that the procedure should be offered to patients with hearing progression based on their SDSs and/or associated progressive increases in their wave III and V latencies on ABRs.

The LaryngoscopeVolume 126, Issue 11 p. 2597-2600 Otology/Neurotology Infrared videoangiographic assessment of cochlear nerve vasculature during middle fossa surgery Nicolas-Xavier Bonne MD, Corresponding Author Nicolas-Xavier Bonne MD nicolas.bonne@chru-lille.fr Department of Otology and Neurotology, University Hospital of Lille, and INSERM U1008 Controlled Drug Delivery Systems and Biomaterials, University of Lille, Lille, FranceSend correspondence to Nicolas-Xavier Bonne, MD, MSc, University Hospital of Lille, Department of Otology and Neurotology, rue E. Laine, 59037 Lille Cedex, France. E-mail: nicolas.bonne@chru-lille.frSearch for more papers by this authorMichaël Risoud MD, Michaël Risoud MD Department of Otology and Neurotology, University Hospital of Lille, and INSERM U1008 Controlled Drug Delivery Systems and Biomaterials, University of Lille, Lille, FranceSearch for more papers by this authorEric P. Wilkinson MD, Eric P. Wilkinson MD House Clinic, Los Angeles, California, U.S.ASearch for more papers by this authorRabih Aboukais MD, Rabih Aboukais MD Department of Neurosurgery, University Hospital of Lille, Lille, FranceSearch for more papers by this authorMarc Baroncini MD, PhD, Marc Baroncini MD, PhD Department of Neurosurgery, University Hospital of Lille, Lille, FranceSearch for more papers by this authorJean-Paul Lejeune MD, Jean-Paul Lejeune MD Department of Neurosurgery, University Hospital of Lille, Lille, FranceSearch for more papers by this authorChristophe Vincent MD, PhD, Christophe Vincent MD, PhD Department of Otology and Neurotology, University Hospital of Lille, and INSERM U1008 Controlled Drug Delivery Systems and Biomaterials, University of Lille, Lille, FranceSearch for more papers by this author Nicolas-Xavier Bonne MD, Corresponding Author Nicolas-Xavier Bonne MD nicolas.bonne@chru-lille.fr Department of Otology and Neurotology, University Hospital of Lille, and INSERM U1008 Controlled Drug Delivery Systems and Biomaterials, University of Lille, Lille, FranceSend correspondence to Nicolas-Xavier Bonne, MD, MSc, University Hospital of Lille, Department of Otology and Neurotology, rue E. Laine, 59037 Lille Cedex, France. E-mail: nicolas.bonne@chru-lille.frSearch for more papers by this authorMichaël Risoud MD, Michaël Risoud MD Department of Otology and Neurotology, University Hospital of Lille, and INSERM U1008 Controlled Drug Delivery Systems and Biomaterials, University of Lille, Lille, FranceSearch for more papers by this authorEric P. Wilkinson MD, Eric P. Wilkinson MD House Clinic, Los Angeles, California, U.S.ASearch for more papers by this authorRabih Aboukais MD, Rabih Aboukais MD Department of Neurosurgery, University Hospital of Lille, Lille, FranceSearch for more papers by this authorMarc Baroncini MD, PhD, Marc Baroncini MD, PhD Department of Neurosurgery, University Hospital of Lille, Lille, FranceSearch for more papers by this authorJean-Paul Lejeune MD, Jean-Paul Lejeune MD Department of Neurosurgery, University Hospital of Lille, Lille, FranceSearch for more papers by this authorChristophe Vincent MD, PhD, Christophe Vincent MD, PhD Department of Otology and Neurotology, University Hospital of Lille, and INSERM U1008 Controlled Drug Delivery Systems and Biomaterials, University of Lille, Lille, FranceSearch for more papers by this author First published: 10 February 2016 https://doi.org/10.1002/lary.25859Citations: 2 The authors have no funding, financial relationships, or conflicts of interest to disclose. Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat Citing Literature Volume126, Issue11November 2016Pages 2597-2600 RelatedInformation

The Mongolian gerbil (Meriones unguiculatus) is commonly used in hearing research because the hearing frequency spectrum of the gerbil is rather similar to that of the human being. However, a precise description of the surgical post-auricular route has not been reported. The aim of this technical note is to provide details on the procedure and the surgical anatomy of the post-auricular route in the Mongolian gerbil. Surgery was performed under general anesthesia on eight (2 males and 6 females) adult Mongolian gerbils. All steps of the post-auricular route were detailed. This surgery provided an access to the following structures: the semi-circular posterior and lateral canals, the external auditory meatus, the tympanic membrane, the round window, the stapes, the stapedial artery and the reliefs of the cochlea. No anatomic variation was noticed among the 8 animals. This post-auricular route in the Mongolian gerbil defines a brief and simple surgery, overall standardized as a consequence of the absence of common anatomic variation, with painless and uncomplicated post-operative stage.