Management of vestibular dysfunction and hearing loss in intralabyrinthine schwannomas.

PURPOSE: Intralabyrinthine schwannomas (ILS) are rare, benign, slow-growing tumors arising from schwann cells of the cochlear or vestibular nerves within the bony labyrinth. This study provides insight into the management of this rare tumor through a large case series. MATERIALS AND METHODS: After Institutional Review Board approval, a retrospective chart review was performed of all ILS patients treated at our institution between 2007 and 2019. RESULTS: 20 patients (9 male, 11 female) with ILS were managed at our institution. The right ear was affected in 9 patients (45%) and the left in 11 (55%). Subjective hearing loss was endorsed by all 20 patients. Average pure tone average at presentation was 72 dB nHL. Nine tumors (45%) were intravestibular, 6 (30%) were intracochlear, 4 (20%) were transmodiolar and 1 (5%) was intravestibulocochlear. Hearings aids were used in 3 patients (15%), BiCROS in 2 (10%), CI in 2 (10%), and bone conduction implant in 1 (5%). Vestibular rehabilitation was pursued in 5 patients. Surgical excision was performed for one patient (5%) via translabyrinthine approach due to intractable vertigo. No patients received radiotherapy or intratympanic gentamicin injections. CONCLUSION: ILS presents a diagnostic and management challenge given the similarity of symptoms with other disorders and limited treatment options. Hearing loss may be managed on a case-by-case basis according to patient symptoms while vestibular loss may be mitigated with vestibular therapy. Surgical excision may be considered in patients with intractable vertigo, severe hearing loss with concurrent CI placement, or in other case-by-case situations.

Recovery of ocular and cervical vestibular evoked myogenic potentials after treatment of inner ear diseases.

Purpose: This study aimed to assess the clinical value of ocular vestibular evoked myogenic potential (oVEMP) and cervical vestibular evoked myogenic potential (cVEMP) for monitoring the rehabilitation of vestibular function in patients treated for peripheral vertigo. Materials and methods: Fifteen patients who had been diagnosed with peripheral vertigo and showed no VEMP response on the affected side but exhibited symptom alleviation and VEMP responses after therapies were retrospectively enrolled. We analyzed the restoration and parameters of their VEMP response. Results: After treatment, six patients with sudden sensorineural hearing loss showed VEMP recovery, including two with both oVEMP and cVEMP recovery, three with oVEMP recovery only, and one with cVEMP recovery only. Two patients with Meniere's disease (MD) showed cVEMP recovery, while the other three MD patients showed oVEMP recovery. Three patients with herpes zoster oticus exhibited cVEMP recovery. One patient with vestibular neuritis exhibited cVEMP recovery. Among the patients with cVEMP and/or oVEMP restoration, most patients presented normal VEMP parameters; however, some patients showed abnormal VEMP parameters after treatment. Conclusion: Combined oVEMP and cVEMP are objective tools for assessing vestibular otolithic end organ function during dynamic functional recovery from vestibular diseases.

Inner ear drug delivery using liposomes.

Dysfunction of inner ear can result in from several disease procedures and introduce a possibility for therapeutic intervention. The existence of a blood-cochlear obstacle and round window membrane restricts direct access into the inner ear and following inner ear drug, gene, protein and cell delivery. Several strategies have designed to increase drug delivery to the inner ear. One of main particles for inner ear drug delivery is liposome. Here we reviewed the application of liposomes in inner ear drug delivery.

Posterior semicircular canal dehiscence secondary to jugular enlargement.

Semicircular canal dehiscence is an important entity often presenting with symptoms of noise or pressure induced vertigo, autophony, aural fullness and conductive hearing loss. Due to its varied presentation and mimic of other otologic conditions its consideration is of increased importance. Within we report a case of right sided posterior semicircular canal dehiscence secondary to an enlarged and high jugular bulb. The results of this observation indicate a need for patients with auditory symptoms and high riding jugular bulbs to be evaluated for possible posterior semicircular canal dehiscence.

Pneumo-Membranous Labyrinth After Hyperbaric Oxygen Therapy for Sudden Sensorineural Hearing Loss.

Pneumo-membranous labyrinth is an almost unique condition, in which air extends into the membranous labyrinth, filling the endolymphatic sac through the vestibular aqueduct. In this manuscript, we describe and discuss a case of pneumo-membranous labyrinth, with air bubbles extending also to the endolymphatic sac, resulting in anacusis, following hyperbaric oxygen therapy for sudden sensorineural hearing loss. The patient was successfully rehabilitated with a cochlear implant, obtaining a pure-tone average of 30 dB, with a speech discrimination score of 100% at 70 dB. Laryngoscope, 134:3773-3777, 2024.

Reversible opening of the blood-labyrinth barrier by low-pressure pulsed ultrasound and microbubbles for the treatment of inner ear diseases.

Systemic drug administration provides convenience and non-invasive benefits for preventing and treating inner ear diseases. However, the blood-labyrinth barrier (BLB) restricts the transport of drugs to inner ear tissues. Ultrasound can stimulate specific areas and penetrate tissues, with the potential to overcome physiological barriers. We present a novel strategy based on low-pressure pulsed ultrasound assisted by microbubbles (USMB) to transiently open the BLB and deliver therapeutics into the inner ear. A pulsed ultrasound device with adjustable pressure was established; the generated ultrasound was transmitted through the external auditory canal into the guinea pig's inner ear. We observed that the application of microbubbles allowed the use of safe and efficient ultrasound conditions to penetrate the BLB. We found that USMB-mediated BLB opening seemed to be associated with a reduced expression of the tight junction proteins zonula occludens-1 and occludin. Following intravenous administration, hydrophilic dexamethasone sodium phosphate (DSP), hydrophobic curcumin (CUR), as well as drug-loaded nanoparticles (Fe3O4@CUR NPs) could be efficiently delivered into the inner ear. We observed better drug accumulation in the perilymph of the inner ear, resulting in less drug (cisplatin)-induced ototoxicity. Furthermore, physiological, hematological, and histological studies showed that the modulation of the BLB by low-pressure USMB was a safe process without significant adverse effects. We conclude that USMB could become a promising strategy for the systematic delivery of therapeutics in the treatment of inner ear diseases.

Gene transfer in inner ear cells: a challenging race.

Recent advances in human genomics led to the identification of numerous defective genes causing deafness, which represent novel putative therapeutic targets. Future gene-based treatment of deafness resulting from genetic or acquired sensorineural hearing loss may include strategies ranging from gene therapy to antisense delivery. For successful development of gene therapies, a minimal requirement involves the engineering of appropriate gene carrier systems. Transfer of exogenous genetic material into the mammalian inner ear using viral or non-viral vectors has been characterized over the last decade. The nature of inner ear cells targeted, as well as the transgene expression level and duration, are highly dependent on the vector type, the route of administration and the strength of the promoter driving expression. This review summarizes and discusses recent advances in inner ear gene-transfer technologies aimed at examining gene function or identifying new treatment for inner ear disorders.

Inner ear symptoms and disease: pathophysiological understanding and therapeutic options.

In recent years, huge advances have taken place in understanding of inner ear pathophysiology causing sensorineural hearing loss, tinnitus, and vertigo. Advances in understanding comprise biochemical and physiological research of stimulus perception and conduction, inner ear homeostasis, and hereditary diseases with underlying genetics. This review describes and tabulates the various causes of inner ear disease and defines inner ear and non-inner ear causes of hearing loss, tinnitus, and vertigo. The aim of this review was to comprehensively breakdown this field of otorhinolaryngology for specialists and non-specialists and to discuss current therapeutic options in distinct diseases and promising research for future therapies, especially pharmaceutic, genetic, or stem cell therapy.

Severe capillary leak syndrome after inner ear decompression sickness in a recreational scuba diver.

BACKGROUND: Post-decompression shock with plasma volume deficit is a very rare event that has been observed under extreme conditions of hypobaric and hyperbaric exposure in aviators and professional divers. CASE REPORT: We report a case of severe hypovolemic shock due to extravasation of plasma in a recreational scuba diver presenting with inner ear decompression sickness. Impaired endothelial function can lead to capillary leak with hemoconcentration and hypotension in severe cases. This report suggests that decompression-induced circulating bubbles may have triggered the endothelial damage, activating the classic inflammatory pathway of increased vascular permeability. CONCLUSION: This observation highlights the need for an accurate diagnosis of this potentially life-threatening condition at the initial presentation in the Emergency Department after a diving-related injury. An elevated hematocrit in a diver should raise the suspicion for the potential development of capillary leak syndrome requiring specific treatment using albumin infusion as primary fluid replacement.

[Diagnosis and treatment of post-traumatic perilymphatic fistula: Report of 16 cases]. / Diagnostic et traitement des fistules périlymphatiques post-traumatiques : à propos de 16 cas.

INTRODUCTION: When facing cochleovestibular symptoms such as hearing loss, dizziness or unsteadiness, or a tinnitus evolving in the aftermath of a cranial trauma or overpressure in the form of inner ear barotrauma after diving or a from blast, a perilymphatic fistula must be considered. MATERIALS AND METHODS: We present a homogenous prospective series of 16 cases of perilymphatic fistulae occurring after head trauma or overpressure between 2003 and 2011. Patients suspected of suffering from a perilymphatic fistula and presenting with the following criteria were included: the occurrence after a variable delay of cochleovestibular symptoms (vertigo, tinnitus, and hearing loss) in the aftermath of a head trauma or overpressure. All patients received medical treatment with intravenous corticosteroids. Failure of the initial treatment and in the presence of clinical data suggesting a perilymphatic fistula, an exploration of the middle ear was performed. RESULTS: 13 patients (81.2% underwent surgical exploration with early and stable subtotal recovery of hearing in 90%, a rapid disappearance of vertigo in 89.9%, a loss of tinnitus in 45% and in 27% improvement. CONCLUSION: The diagnosis must be supported by various diagnostic tests. If evidence in favor of a perilymphatic fistula is credible, surgery has always achieved an excellent functional outcome.

A pilot study of rituximab in immune-mediated inner ear disease.

Immune-mediated inner ear disease (IMED) is a cause of rapidly progressive auditory dysfunction. Patients are often responsive to high-dose corticosteroids and the disease is believed to be mediated by an antibody to inner ear proteins. To date, no therapies have proven effective as corticosteroid-sparing agents. Rituximab is a monoclonal antibody that depletes B cells, resulting in a reduction in autoantibody production. For that reason, rituximab was evaluated in a small pilot study in patients with IMED to see if there was a signal suggesting benefit. In all, 5/7 patients met the primary endpoint of an improvement in pure tone average (500-3000 Hz) by 10 dB in at least one ear, or an improvement in word identification score by at least 12% at 24 weeks, both relative to screening precorticosteroid values after 1 course of treatment. No significant adverse events were reported. The results of this study suggest further evaluation of rituximab as a treatment for IMED is indicated.

[Vertigo induced by noise or pressure to the left ear]. / Schwindel durch Lärm oder Druck auf dem linken Ohr.

A 49-year-old male patient presented with recently acquired vertigo induced by noise or pressure to the left ear. With appropriate stimulation, oscillopsia with a rotatory component could be reproduced in videooculography. Cervical vestibular evoked myogenic potentials (VEMP) showed increased amplitudes and a lowered threshold on the left side. CT of the petrous bone showed a bony dehiscence of the left superior semicircular canal. Conservative therapy was initiated as a first step.

[Future therapeutic options for inner ear diseases]. / Tulevaisuuden hoitokeinoja sisäkorvasairauksissa.

Knowledge of the structure, molecular biology and function of the inner ear will enable the research on new modes of treatment such as gene transfers, growth factor treatments and stem cell transfers. With respect to the treatment of inner ear diseases in humans, at present the majority of these means remain at an experimental level. Improvement of hearing has, however, been achieved in various experimental disease models by gene transfer. Regeneration of sensory cells and hair cells from stem cells has opened up new lines of research and treatment options for the restoration of a damaged inner ear.

Canalithiasis of the anterior semicircular canal (ASC): treatment options based on the possible underlying pathogenetic mechanisms.

Benign paroxysmal positional vertigo (BPPV) of the anterior semicircular canal (ASC) is an uncommon disorder currently diagnosed with the Dix-Hallpike (D-H) examination. According to the literature, nystagmus and vertigo may be more pronounced when the affected ear is either up or down. In some patients, both right and left D-H tests can trigger nystagmus with the same direction. The proposed treatment options with the addition of a different manoeuvre applied by the authors of the present study in cases of ASC lithiasis, seem to present a respective variety regarding the position of the affected ASC during the procedure of canalith repositioning. The aim of this study is to analyse the mechanisms underlying both the proposed treatment options and the clinical findings in the D-H examination. The results of this analysis stimulate further investigation, since they probably imply that repositioning manoeuvres might vary in their effectiveness when applied to different clinical subgroups of ASC BPPV.

Practical aspects of inner ear gene delivery for research and clinical applications.

The application of gene therapy is widely expanding in research and continuously improving in preparation for clinical applications. The inner ear is an attractive target for gene therapy for treating environmental and genetic diseases in both the auditory and vestibular systems. With the lack of spontaneous cochlear hair cell replacement, hair cell regeneration in adult mammals is among the most important goals of gene therapy. In addition, correcting gene defects can open up a new era for treating inner ear diseases. The relative isolation and small size of the inner ear dictate local administration routes and carefully calculated small volumes of reagents. In the current review, we will cover effective timing, injection routes and types of vectors for successful gene delivery to specific target cells within the inner ear. Differences between research purposes and clinical applications are also discussed.

Adeno-associated virus gene replacement for recessive inner ear dysfunction: Progress and challenges.

Approximately 3 in 1000 children in the US under 4 years of age are affected by hearing loss. Currently, cochlear implants represent the only line of treatment for patients with severe to profound hearing loss, and there are no targeted drug or biological based therapies available. Gene replacement is a promising therapeutic approach for hereditary hearing loss, where viral vectors are used to deliver functional cDNA to "replace" defective genes in dysfunctional cells in the inner ear. Proof-of-concept studies have successfully used this approach to improve auditory function in mouse models of hereditary hearing loss, and human clinical trials are on the immediate horizon. The success of this method is ultimately determined by the underlying biology of the defective gene and design of the treatment strategy, relying on intervention before degeneration of the sensory structures occurs. A challenge will be the delivery of a corrective gene to the proper target within the therapeutic window of opportunity, which may be unique for each specific defective gene. Although rescue of pre-lingual forms of recessive deafness have been explored in animal models thus far, future identification of genes with post-lingual onset that are amenable to gene replacement holds even greater promise for treatment, since the therapeutic window is likely open for a much longer period of time. This review summarizes the current state of adeno-associated virus (AAV) gene replacement therapy for recessive hereditary hearing loss and discusses potential challenges and opportunities for translating inner ear gene replacement therapy for patients with hereditary hearing loss.