[Radiation-induced parotid leiomyosarcoma]. / Léiomyosarcome parotidien en territoire irradié.

INTRODUCTION: First case of radiation-induced parotid leiomyosarcoma. ANATOMO-CLINICAL OBSERVATION: A 50-year-old woman with a history of cervical irradiation for Hodgkin's lymphoma presented with a right parotid tumefaction. Examination noted a deep adherent pretragal mass with peripheral facial palsy. A total parotidectomy with intra-operative examination and cervical curage was performed. Histopathological analysis concluded to a grade 3 parotid leiomyosarcoma according to the National Federation of Cancer Centers. Adjuvant radiotherapy was performed. After 24 months of follow-up, the patient presented bone and liver metastases without local recurrence. DISCUSSION: This is the first case of radiation-induced leiomyosarcoma and the 12th case of parotid leiomyosarcoma described in the literature. The management associates surgery with adjuvant radiotherapy. Follow-up is by clinical examination, parotid MRI, and annual thoracoabdominal CT scan to search for metastases. Recurrences occur during the first year in 40 to 64% of cases, and distant metastases in 40 to 60% of cases. The 5-year survival rate is between 10 and 30%.

Clinical and biochemical footprints of inherited metabolic diseases. IX. Metabolic ear disease.

Damages to the ear are very diverse and can depend on the type of inherited metabolic diseases (IMD). Indeed, IMDs can affect all parts of the auditory system, from the outer ear to the central auditory process. We have identified 219 IMDs associated with various types of ear involvement which we classified into five groups according to the lesion site of the auditory system: congenital external ear abnormalities, acquired external ear abnormalities, middle ear involvement, inner ear or retrocochlear involvement, and unspecified hearing loss. This represents the ninth issue in a series of educational summaries providing a comprehensive and updated list of metabolic differential diagnoses according to system involvement.

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.

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.

Pediatric thyroid surgery: experience in 75 consecutive thyroidectomies.

OBJECTIVES: The main objective of this study is to report our experience in a university hospital in the surgical management of thyroid disease in pediatric patients. We also aim to analyze the results and evaluate the efficacy of fine-needle aspiration biopsy (FNAB) and frozen section analysis. METHODS: A retrospective review of thyroid surgeries from January 1997 to December 2017 was conducted. Patients aged under 18 who underwent total or partial thyroidectomy were included. The indication of the surgery, the investigation results, the surgical technique used and the final diagnosis were reviewed and analyzed. RESULTS: A total of 75 patients were included. 80% (n = 60) were females and 20% (n = 15) were males. The average age was 13.3 years ± 3.76 and age range was 3-18 years. The indication for thyroidectomy was thyroid nodule in 80% (n = 60), Grave's disease in 13.3% (n = 10), multiple endocrine neoplasm type II (MEN II) in 6.7% (n. 5). FNAB was done in 42.7% (n = 32/75) with sensitivity and specificity of 62.50% and 94.4%, respectively, the positive predictive value was 83.3% and the negative predictive value was 85%. Frozen section, which is a quick intraoperative micro and/or macroscopic examination, was done in 66.7% (n = 50/75). It was malignant in 12% (n = 6/50) and was benign in 88% (n = 44/50). Among benign results, nine (n = 9/44) patients had malignant disease in final pathological diagnosis. Its sensitivity and specificity were 40% and 100%, respectively, the positive predictive value and the negative predictive value were 100% and 79.6%, respectively. Total thyroidectomy was done in 54.7% (n = 41/75) and partial thyroidectomy was done in 45.3% (n = 34/75). Of the 75 patients, 29.3% (n = 22) had thyroid carcinoma on final pathological analysis. CONCLUSION: Thyroid diseases that require surgical intervention are rare in pediatric populations. However, when surgery is indicated, there is higher risk of malignancy compared to adults. Our study showed that FNAB has a lower specificity and sensitivity compared to adults, and that surgical decision should be made considering all investigations. We also showed that frozen section is considered primarily for papillary thyroid carcinoma but is not reliable for follicular carcinoma or Bethesda IV. Finally, thyroid surgery in children and adolescents must be part of global multidisciplinary management.

Binaural Perception in Single-Sided Deaf Cochlear Implant Users with Unrestricted or Restricted Acoustic Hearing in the Non-Implanted Ear.

Cochlear implantation (CI) can benefit patients with single-sided deafness (SSD) in terms of sound localization, speech understanding in noise, tinnitus severity, and quality of life (QoL). In previous studies, CI outcomes have been largely reported for SSD patients with normal "unrestricted" hearing in the contralateral ear. However, SSD patients may often have some degree of hearing loss in the contralateral ear ("restricted" acoustic hearing). In this study, we report results from a French clinical trial for CI in in SSD patients (NCT02204618). Localization, speech reception thresholds (SRTs) in noise, tinnitus severity, and QoL were evaluated in 18 SSD patients 1 year after CI. Data were analyzed for 2 subject groups according to the pure-tone average thresholds in the non-implanted ear: unrestricted acoustic hearing (UNRES; ≤25 dB HL; n = 10) and restricted acoustic hearing (RES; > 25 dB HL; n = 8). Across all subjects, localization was significantly better with the CI on than off (p = 0.005); there was no significant difference between subject groups (p = 0.301). When speech and noise were co-located (S0N0), there was no significant difference in SRTs with the CI on or off (p = 0.480); SRTs were significantly better for the UNRES than for the RES group (p = 0.005). When speech and noise were spatially separated (SCINNH), SRTs were significantly better with the CI on than off (p < 0.001). While SRTs were better for the UNRES than for the RES group (p = 0.024), the CI benefit was more than 50% greater for the RES group due to the restoration of high-frequency speech cues. Questionnaire data showed that tinnitus severity was significantly reduced (p = 0.045) and QoL was significantly improved after one year of experience with the CI (p < 0.001). Age at testing was significantly correlated with SRTs for the S0N0 condition; duration of deafness was correlated with SRTs for the SCINNH condition. There were relatively few correlations between behavioral and subjective measures, suggesting that both were valuable when assessing CI benefits for SSD patients. The present data suggest that indications for CI should be expanded to include unilaterally deaf patients who have normal hearing or mild-to-moderate hearing loss in the non-implanted ear.

Cortical Processing of Vocal and Nonvocal Sounds in Cochlear-Implanted Children: An Electrophysiological Study.

OBJECTIVES: For prelingually deaf children, cochlear implants (CIs) can restore auditory input to the auditory cortex and the ability to acquire spoken language. Language development is strongly intertwined with voice perception. The aim of this electrophysiological study was to investigate human voice processing using measures of cortical auditory evoked potentials (AEPs) in pediatric CI users. DESIGN: Cortical AEPs were measured in 8 CI children (4 to 12 years old) with good auditory and language performance and 8 normal-hearing (NH) age-matched controls. The auditory stimuli were nonspeech vocal sounds (laughing, sighing, coughing) and environmental sounds (e.g., telephones, alarms, cars, bells, water, wind). Independent component analysis was used to minimize the CI artifact in cortical AEPs. RESULTS: Fronto-temporal positivity to vocal sounds was found in NH children, with a significant effect in the 140 to 240 msec latency range. In CI children, there was a positive response to vocal sounds in the 170 to 250 msec latency range, with a more diffuse and anterior distribution than in the NH children. CONCLUSIONS: Cortical responses to vocal sounds were recorded in CI children. The topography and latency of response to voice differed from that of NH children. The results suggest that cortical reorganization for processing vocal sounds may occur in congenitally deaf children fitted with a CI.

Audiometric evaluation in patients with Alzheimer's disease.

The objective of this study is to assess the validity of ASSR as a complementary diagnostic test for peripheral hearing loss by proving a significant correlation between behavioral thresholds and ASSR. The design used in this study is monocentric prospective study from November 2014 to April 2015. The setting used in this study is the ENT-Head and Neck Surgery Department and Geriatrics Department in a French Regional and University Hospital. The participants are patients over 75 years with cognitive impairment (Alzheimer's disease or mild-cognitive impairment) with a Mini-Mental State Examination score under 27/30 and without hearing aids. Exclusion criteria were: otoscopic and middle ear abnormalities, retro-cochlear lesion, other types of dementia, and central nervous system disease altering cerebral lateralization. The intervention used in this study is pure-tone audiometry, speech audiometry, dichotic listening test, and auditory steady-state responses recording. The correlations between these exams were studied with Pearson's correlation coefficient and Student's t test. Results were significant if p < 0.05. Twenty-three ears were analyzed from 12 patients. There were six women and six men with cognitive impairment, mean age 82.1 (±4.6) years, and mean MMSE score that was 21.3/30 (±5.7). The correlation between pure-tone audiometry and ASSR was significant for all frequencies: r = 0.55 (p = 0.006) for 500 Hz, r = 0.58 (p = 0.005) for 1000 Hz, r = 0.61 (p = 0.003) for 2000 Hz, and r = 0.66 (p = 0.002) for 4000 Hz. There was no significant correlation between the MMSE and the difference between ASSR and PTA on each frequency. The dichotic listening test showed a right ear advantage (50.9 %, p = 0.039). The ASSR in patients with cognitive impairment and understanding troubles is a promising complementary technique to estimate the hearing thresholds.

Management of laryngoceles by transoral robotic surgery.

We herein report our experience with the management of laryngoceles using transoral robotic surgery (TORS). A bicentric retrospective study was conducted from November 2009 to September 2015. The inclusion criteria were treatment of a laryngocele by TORS and no malignancy on definitive histopathology. Surgery was performed using the Da Vinci (Intuitive®) surgical robot. Surgical methods and post-operative outcomes were evaluated. Eight patients (four men and four women) presenting with a laryngocele (one bilateral case) were included (mean age 61.8 years). There was one covering tracheotomy. The average post-operative stay was 3.75 days. Three patients treated for a combined laryngocele had a nasogastric feeding tube inserted for 5 days. One patient experienced late laryngeal bleeding that required surgical treatment. TORS may offer an efficient treatment option for laryngoceles. The use of precise and flexible instruments and a three-dimensional camera allow fine dissection of these tumours, preserving the glottic space and vocal function, even for combined laryngoceles extending deep within the neck.Evidence level: 4.

Head Spear Gun Injury: An Atypical Suicide Attempt.

Weapon injuries with spear gun are rare. The aim of this case report is to report the emergency and surgical management when this event occurs. A 35-year-old man attempted suicide with a spear gun. The entry of the shaft was localized through the submental area without an obvious exit point. The projectile passed through the tongue and palatal bone. A tracheotomy was performed. Preoperative cranial computed tomography (CT) showed the harpoon was gone upward through the submental area, the oral cavity, the ethmoid paranasal sinus, the cribriform plate, and the frontal region without vessel damages. Under general anesthesia, the harpoon was pulled out in order to extract the shaft tip and the articulated wishbone. Osteo-meningeal defect of the ethmoid roof was closed using a middle turbinate flap. There were no neurologic deficit and no cerebro-spinal rhinorrhea at his 3-year follow-up visit. The trajectory of the shaft is different between attempted suicide and accident. Cranial CT scan is helpful to show the trajectory of the shaft. Angiogram can be helpful to see the relations between the tip shaft and the vessels. The knowledge of the shaft tip and the imagery findings are important to decide the best surgical approach.

Microbubble-assisted ultrasound for inner ear drug delivery.

Treating pathologies of the inner ear is a major challenge. To date, a wide range of procedures exists for administering therapeutic agents to the inner ear, with varying degrees of success. The key is to deliver therapeutics in a way that is minimally invasive, effective, long-lasting, and without adverse effects on vestibular and cochlear function. Microbubble-assisted ultrasound ("sonoporation") is a promising new modality that can be adapted to the inner ear. Combining ultrasound technology with microbubbles in the middle ear can increase the permeability of the round window, enabling therapeutic agents to be delivered safely and effectively to the inner ear in a targeted manner. As such, sonoporation is a promising new approach to treat hearing loss and vertigo. This review summarizes all studies on the delivery of therapeutic molecules to the inner ear using sonoporation.

Carcinomas of the external auditory canal: Management and results: A multicenter REFCOR propensity score matching study.

OBJECTIVES: To analyse prognostic factors and survival outcomes of malignant tumors of the external auditory canal, to investigate the role of regional surgery, and adjuvant radiotherapy in early stages and to investigate the role of surgery in operable T4 stage. SETTING: A retrospective analysis was conducted on all patients prospectively included in the national database of the French Expertize Network for Rare ENT Cancers (REFCOR) from January 2000 to December 2016. PARTICIPANTS: 103 patients from 19 reference centers were included. A propensity score matching analysis was applied to enable comparisons between treatments. MAIN OUTCOMES AND MEASURES: Event-free survival, overall survival and factors of poor prognosis of the cohort were described. The interest of local and regional surgery and postoperative radiotherapy were evaluated. RESULTS: The factors of poor prognosis on event-free survival were immunosuppression (p = 0.002), Karnofsky status less than 90% (p = 0.02), body mass index less than 19 Kg / m2 (p = 0.0009), peripheric facial palsy (p = 0.0016), and positive margin (p = 0.0006). In early stages, locoregional surgery was associated with an increase in event-free survival (p = 0.003, HR = 0.21) versus local surgery alone, while postoperative radiotherapy was not associated with an increase in event-free survival (p = 0.86, HR = 0.91) or overall (p = 0.86, HR = 0.91). In locally advanced stages, locoregional surgery followed by radiotherapy was associated with an increase in event-free survival (p = 0.03, HR = 0.39) and overall (p = 0.02, HR = 0.34) versus chemoradiotherapy alone. CONCLUSION AND RELEVANCE: Regional surgery is recommended for early stages of cancers of the external auditory canal. In operable cases, locoregional surgery followed by radiotherapy is recommended.

Preliminary evaluation of computer-assisted home training for French cochlear implant recipients.

For French cochlear implant (CI) recipients, in-person clinical auditory rehabilitation is typically provided during the first few years post-implantation. However, this is often inconvenient, it requires substantial time resources and can be problematic when appointments are unavailable. In response, we developed a computer-based home training software ("French AngelSound™") for French CI recipients. We recently conducted a pilot study to evaluate the newly developed French AngelSound™ in 15 CI recipients (5 unilateral, 5 bilateral, 5 bimodal). Outcome measures included phoneme recognition in quiet and sentence recognition in noise. Unilateral CI users were tested with the CI alone. Bilateral CI users were tested with each CI ear alone to determine the poorer ear to be trained, as well as with both ears (binaural performance). Bimodal CI users were tested with the CI ear alone, and with the contralateral hearing aid (binaural performance). Participants trained at home over a one-month period (10 hours total). Phonemic contrast training was used; the level of difficulty ranged from phoneme discrimination in quiet to phoneme identification in multi-talker babble. Unilateral and bimodal CI users trained with the CI alone; bilateral CI users trained with the poorer ear alone. Outcomes were measured before training (pre-training), immediately after training was completed (post-training), and one month after training was stopped (follow-up). For all participants, post-training CI-only vowel and consonant recognition scores significantly improved after phoneme training with the CI ear alone. For bilateral and bimodal CI users, binaural vowel and consonant recognition scores also significantly improved after training with a single CI ear. Follow-up measures showed that training benefits were largely retained. These preliminary data suggest that the phonemic contrast training in French AngelSound™ may significantly benefit French CI recipients and may complement clinical auditory rehabilitation, especially when in-person visits are not possible.

Sonoporation of the Round Window Membrane on a Sheep Model: A Safety Study.

Sonoporation using microbubble-assisted ultrasound increases the permeability of a biological barrier to therapeutic molecules. Application of this method to the round window membrane could improve the delivery of therapeutics to the inner ear. The aim of this study was to assess the safety of sonoporation of the round window membrane in a sheep model. To achieve this objective, we assessed auditory function and cochlear heating, and analysed the metabolomics profiles of perilymph collected after sonoporation, comparing them with those of the control ear in the same animal. Six normal-hearing ewes were studied, with one sonoporation ear and one control ear for each. A mastoidectomy was performed on both ears. On the sonoporation side, Vevo MicroMarker® microbubbles (MBs; VisualSonics-Fujifilm, Amsterdam, The Netherlands) at a concentration of 2 × 108 MB/mL were locally injected into the middle ear and exposed to 1.1 MHz sinusoidal ultrasonic waves at 0.3 MPa negative peak pressure with 40% duty cycle and 100 µs interpulse period for 1 min; this was repeated three times with 1 min between applications. The sonoporation protocol did not induce any hearing impairment or toxic overheating compared with the control condition. The metabolomic analysis did not reveal any significant metabolic difference between perilymph samples from the sonoporation and control ears. The results suggest that sonoporation of the round window membrane does not cause damage to the inner ear in a sheep model.

[Early management of presbycusis: recommendations from the French Society of Otorhinolaryngology and Head and Neck Surgery, the French Society of Audiology, and the French Society of Geriatrics and Gerontology]. / Recommandations de la Société française d'otorhinolaryngologie et de chirurgie de la face et du cou, la Société française d'audiologie et la Société française de gériatrie et gérontologie pour la prise en charge précoce de la presbyacousie.

INTRODUCTION: Presbycusis is the physiological decrease in hearing due to advancing age and begins well before the sixth decade. These recommendations recall the principles of early diagnosis of presbycusis and the means of optimal rehabilitation as soon as the first symptoms appear. MATERIAL AND METHODS: The recommendations are based on a systematic analysis of the literature carried out by a multidisciplinary group of doctors and audioprosthetists from all over France. They are graded A, B, C or expert opinion according to decreasing level of scientific evidence. RESULTS: The diagnosis of presbycusis is more difficult at the beginning of its evolution but a certain number of tools are available for its early diagnosis and its management in face-to-face or even distance learning. CONCLUSION: In case of a clinical profile suggestive of presbycusis in a young subject, especially if there are several family cases, it is recommended to propose a genetic investigation. It is recommended to perform free-field speech audiometry in noise to measure intelligibility in an environment as close as possible to reality. Questionnaires can be used in addition to audiometry to best assess the patient's disability. It is recommended that hearing rehabilitation with a hearing aid or cochlear implant may slow or prevent cognitive decline. Combined auditory and cognitive rehabilitation should be offered regardless of the time elapsed since the fitting. It is recommended to integrate programs accessible via smartphones, tablets or the Internet, integrating different training domains in addition to face-to-face sessions.

Early management of presbycusis: recommendations from the French Society of Otorhinolaryngology and Head and Neck Surgery, the French Society of Audiology, and the French Society of Geriatrics and Gerontology.

INTRODUCTION: Presbycusis is the physiological decrease in hearing due to advancing age and begins well before the sixth decade. These recommendations recall the principles of early diagnosis of presbycusis and the means of optimal rehabilitation as soon as the first symptoms appear. MATERIAL AND METHODS: The recommendations are based on a systematic analysis of the literature carried out by a multidisciplinary group of ENT physicians, audiologists, geriatricians and hearing specialists from all over France. They are classified as grade A, B, C or professional agreement according to a decreasing level of scientific evidence. RESULTS: The diagnosis of presbycusis is more difficult at the beginning of its evolution but a certain number of tools are available for its early diagnosis and its face-to-face or remote management. CONCLUSION: In the case of a clinical profile suggestive of presbycusis in a young subject, especially if there are several family cases, it is recommended to propose a genetic investigation. Free-field speech audiometry in noise is recommended to measure intelligibility in a realistic environment. Questionnaires in addition to audiometric tests would allow the best assessment of the patient's disability. Hearing rehabilitation with a hearing aid or cochlear implant may slow or prevent cognitive decline. Combined auditory and cognitive rehabilitation should be offered regardless of the time since the hearing was fitting. It is recommended to integrate programs accessible via smartphones, tablets or the Internet, that include different training domains to complement face-to-face sessions.

Metabolomic Studies in Inner Ear Pathologies.

Sensorineural hearing loss is the most common sensory deficit. The etiologies of sensorineural hearing loss have been described and can be congenital or acquired. For congenital non-syndromic hearing loss, mutations that are related to sites of cochlear damage have been discovered (e.g., connexin proteins, mitochondrial genes, etc.). For cytomegalovirus infection or auditory neuropathies, mechanisms are also well known and well researched. Although the etiologies of sensorineural hearing loss may be evident for some patients, the damaged sites and pathological mechanisms remain unclear for patients with progressive post-lingual hearing loss. Metabolomics is an emerging technique in which all metabolites present in a sample at a given time are analyzed, reflecting a physiological state. The objective of this study was to review the literature on the use of metabolomics in hearing loss. The findings of this review suggest that metabolomic studies may help to develop objective tests for diagnosis and personalized treatment.

Immediate-Early Modifications to the Metabolomic Profile of the Perilymph Following an Acoustic Trauma in a Sheep Model.

The pathophysiological mechanisms of noise-induced hearing loss remain unknown. Identifying biomarkers of noise-induced hearing loss may increase the understanding of pathophysiological mechanisms of deafness, allow for a more precise diagnosis, and inform personalized treatment. Emerging techniques such as metabolomics can help to identify these biomarkers. The objective of the present study was to investigate immediate-early changes in the perilymph metabolome following acoustic trauma. Metabolomic analysis was performed using liquid chromatography coupled to mass spectrophotometry to analyze metabolic changes in perilymph associated with noise-induced hearing loss. Sheep (n = 6) were exposed to a noise designed to induce substantial hearing loss. Perilymph was collected before and after acoustic trauma. Data were analyzed using univariate analysis and a supervised multivariate analysis based on partial least squares discriminant analysis. A metabolomic analysis showed an abundance of 213 metabolites. Four metabolites were significantly changed following acoustic trauma (Urocanate (p = 0.004, FC = 0.48), S-(5'-Adenosyl)-L-Homocysteine (p = 0.06, FC = 2.32), Trigonelline (p = 0.06, FC = 0.46) and N-Acetyl-L-Leucine (p = 0.09, FC = 2.02)). The approach allowed for the identification of new metabolites and metabolic pathways involved with acoustic trauma that were associated with auditory impairment (nerve damage, mechanical destruction, and oxidative stress). The results suggest that metabolomics provides a powerful approach to characterize inner ear metabolites which may lead to identification of new therapies and therapeutic targets.