Detecting endolymphatic hydrops in patients with cranial nerve VIII schwannoma using hydrops MR examination.

PURPOSE: This study utilized Hydrops MRI in patients with cranial nerve (CN) VIII schwannoma to assess the concomitance with endolymphatic hydrops (EH), aiming to elucidate the mechanism of hydrops formation in these patients. METHODS: Twenty-six patients diagnosed as CN VIII schwannoma including vestibular schwannoma (VS) in 24 and intracochlear schwannoma (ICS) in 2 were enrolled. Fifteen patients received radiosurgery and 11 patients opted for a wait-and-scan approach. All patients underwent an inner ear test battery, followed by Hydrops MRI. Based on Hydrops MRI, 6 patients (23%) with positive EH were assigned to Group A, while the other 20 patients showing negative EH were assigned to Group B. RESULTS: The abnormality rates of inner ear test battery in Group A ran from the audiometry (100%), cervical vestibular-evoked myogenic potential (cVEMP) test (83%), ocular VEMP (oVEMP) test (67%) to the caloric test (33%), exhibiting a significantly declining sequence. This declining sequence is consistent with the decreasing order in the prevalence of EH from the cochlea (83%), saccule (50%) to utricle (50%). However, Group B did not show such decreasing trend, indicating that Groups A and B did not share the common mechanism. The mean tumor size prior to radiosurgery was 1.91 ± 0.89 cm, which significantly reduced to 1.53 ± 0.60 cm at a mean interval of 6 years following radiosurgery. In contrast, tumor size remained unchanged in those opted for a wait-and-scan approach. CONCLUSION: It is recommended to utilize Hydrops MRI for patients with CN VIII schwannoma during annual follow-up, particularly those experienced episodic vertigo and/or deteriorated hearing. The Hydrops MRI can not only monitor tumor size, but also detect the presence of EH, so as to guide treatment decision.

Correlation between the etiology of severe hearing loss and endolymphatic hydrops.

PURPOSE: This study aimed to investigate correlation between the presence of endolymphatic hydrops(EH) and factors such as causes of hearing loss, patient age, duration of deafness, and results of vestibular function tests. METHODS: We retrospectively reviewed medical charts of 128 ears of cochlear implantees who were not considered relevant to Meniere's disease. RESULTS: When comparing group with genetic variants of GJB2, SLC26A4, LMX1A and other genetic mutation group, the proportion of vestibular EH and cochlear EH found in group with genetic variants of GJB2, SLC26A4, LMX1A was significantly higher than group with other genetic etiology (p < 0.01) or the group with all the other causes of hearing loss (p < 0.01). The rate of vestibular and cochlear EH detection was higher in younger patients (41.5% and 35.4%) than in older patients (25.4% and 20.6%). A higher ratio of vestibular and cochlear EH was observed in patients with a longer duration of deafness (37.5% and 31.3%) than those with a shorter duration of deafness (29.7% and 25.0%). The group with vestibular EH showed a higher incidence of abnormal findings in the caloric test (42.9%) than the group without vestibular EH (28.2%). CONCLUSION: Patients with genetic variants of GJB2, SLC26A4, LMX1A, younger patients, those with longer deaf durations showed a higher prevalence of vestibular and cochlear EH, implying EH appears to be formed as a developmental disorder in association with a certain set of genetic variants, rather than a phenotypic marker as a result of severe to profound hearing loss.

The characteristics of three-dimensional real inversion recovery MRI sequence in delayed Meniere's disease.

BACKGROUND: Delayed Meniere's disease (DMD) is characterized by episodic vertigo occurring after a significant delay following longstanding sensorineural hearing loss. However, its pathogenesis and characteristics remain unclear. OBJECTIVES: To explore the characteristics of endolymphatic hydrops (EH) in DMD and investigate its pathology using MRI. MATERIALS AND METHODS: 17 patients diagnosed with DMD were included in this study. A 3D-real-IR MRI sequence was utilized to visualize and grade EH. The signal intensity of the basal cochlear turn was compared to that of the cerebellar white matter to calculate the CC ratio. A paired t-test was employed to assess the differences in the CC ratio between the affected and unaffected sides in patients with unilateral DMD. RESULTS: EH was present in 100% of cases on the affected side. Unilateral EH was seen in 82.4%, and bilateral EH in 23.5%. Vestibular EH without cochlear involvement occurred in 29.4%, and cochlear EH without vestibular involvement in 5.9%. The CC ratio was significantly higher on the affected side (p < 0.01). CONCLUSIONS AND SIGNIFICANCE: A significant grade of vestibular EH was observed in DMD, with bilateral EH being relatively common. The increased contrast on the affected side may reflect the underlying pathology in DMD patients.

The relationship between endolymphatic hydrops features and hearing loss in Bilateral Meniere's disease.

BACKGROUND: This study aimed to investigate the relationship between the features of endolymphatic hydrops and hearing loss in patients with Bilateral Meniere's Disease. METHODS: A retrospective analysis was conducted on 77 patients diagnosed with Bilateral Meniere's Disease. The features of endolymphatic hydrops in the affected ear were evaluated through gadolinium-enhanced inner ear Magnetic resonance imaging. The Spearman correlation coefficient, paired t-tests, and Wilcoxon signed-rank tests were employed for data analysis. RESULTS: The analysis revealed a significant correlation between the degree of endolymphatic hydrops and hearing loss across all frequencies(0.125-8 kHz), including the cochlear, vestibular, and overall degree of endolymphatic hydrops. The strongest correlation between the overall degree of endolymphatic hydrops and hearing loss was observed at low frequencies (r = 0.571, p < 0.05), followed by mid-frequencies (r = 0.508, p < 0.05), and high-frequencies (r = 0.351, p < 0.05), with a correlation of r = 0.463, p < 0.05 for the staging of Meniere's disease. Affected Ears with endolymphatic hydrops both in the cochlea and vestibule exhibited more severe hearing loss and Meniere's disease staging compared to those with isolated endolymphatic hydrops within the same patient. CONCLUSIONS: The features of endolymphatic hydrops in patients with Bilateral Meniere's Disease were found to correlate with the severity of hearing loss and the staging of Meniere's disease.

The clinical manifestation and treatment of Meniere's Disease from the viewpoint of the water homeostasis of the inner ear.

Endolymphatic hydrops, a pathological feature of Ménière's disease, has been experimentally and clinically confirmed to be influenced by the blood circulation of vasopressin (VP). VP is a well-known hormonal regulator of water homeostasis. In addition, VP is influenced by various environmental changes, dehydration, fluctuation of atmospheric pressure, pregnancy, and other factors. Furthermore, VP is a key regulator of the hypothalamic-pituitary-adrenal (HPA) axis. The HPA axis is a major neuroendocrine system that controls reactions to emotional and physical stresses, as well as the sleep/wake cycle (circadian rhythm). Therefore, VP is susceptible to change via the HPA axis. This review considers possible mechanisms of the formation of endolymphatic hydrops from the perspective of the vasopressin-aquaporin 2 system.

Association of contrast-enhanced MRI of inner ear and caloric response in patients with clinically diagnosed ipsilateral delayed endolymphatic hydrops.

BACKGROUND: Patients with delayed endolymphatic hydrops (DEH) often show caloric hypofunction and endolymphatic hydrops (ELH) on gadolinium (Gd) enhanced magnetic resonance imaging (MRI) of the inner ear. OBJECTIVES: We aimed to investigate the relationship between the ELH in vivo and caloric results in ipsilateral DEH. MATERIAL AND METHODS: Twelve patients with ipsilateral DEH were included, who underwent delayed MRI following intratympanic Gd application, pure-tone audiometry, caloric test, and video head impulse test (vHIT). RESULTS: For the affected ears, the overall prevalence of inner ear hydrops was 91.7%, including 75% in the cochlear and 50% in vestibular compartment. For the non-affected ears, the overall prevalence of inner ear hydrops was 25%, including 25% in cochlear and 16.7% in vestibular region. Caloric hypofunction was demonstrated in 75% of the affected ears. No pathologic vHIT were found. Caloric results were in agreement with the radiological evidence of inner ear hydrops on affected and non-affected ears in 9 cases. There was fair concordance between inner ear hydrops and canal paresis abnormality on the affected side. CONCLUSIONS AND SIGNIFICANCE: MRI provides auxiliary evidence of ELH in vivo in the ipsilateral DEH-affected ears. The association between morphological alterations and caloric hypofunction warrants further investigation.

A Pediatric Case of Cogan's Syndrome With Internal Otitis.

Cogan's syndrome is characterized by ocular symptoms and auditory vestibular dysfunction. Auditory vestibular dysfunction in Cogan's syndrome is believed to be similar to Ménière's disease, but the cause is not known in detail. We present the case of a 10-year-old boy with Cogan's syndrome. The patient had panuveitis, bilateral hearing loss, and bilateral vestibular dysfunction. MRI revealed no evidence of endolymphatic hydrops, which is a cause of Ménière's disease, and enhanced contrast effects on the bilateral cochlear and vestibular apparatus. The caloric test, the video-head impulse test, and the vestibular evoked muscle potential test also showed severe vestibular dysfunction. Based on the above, the auditory vestibular dysfunction in this patient was considered to be caused by internal otitis. The patient's vision recovered after treatment with steroids and immunosuppressive drugs, but his hearing did not recover. He underwent bilateral cochlear implantation and had a good postoperative course but we encountered difficulty in deciding when to perform cochlear implantation. This case demonstrates the importance of determining the timing of surgery in consideration of the ossification and fibrosis of the inner ear and the drug administration status.

Applications of Machine Learning in Meniere's Disease Assessment Based on Pure-Tone Audiometry.

OBJECTIVE: To apply machine learning models based on air conduction thresholds of pure-tone audiometry for automatic diagnosis of Meniere's disease (MD) and prediction of endolymphatic hydrops (EH). STUDY DESIGN: Retrospective study. SETTING: Tertiary medical center. METHODS: Gadolinium-enhanced magnetic resonance imaging sequences and pure-tone audiometry data were collected. Subsequently, basic and multiple analytical features were engineered based on the air conduction thresholds of pure-tone audiometry. Later, 5 classical machine learning models were trained to diagnose MD using the engineered features. The models demonstrating excellent performance were also selected to predict EH. The model's effectiveness in MD diagnosis was compared with experienced otolaryngologists. RESULTS: First, the winning light gradient boosting (LGB) machine learning model trained by multiple features demonstrates a remarkable performance on the diagnosis of MD, achieving an accuracy rate of 87%, sensitivity of 83%, specificity of 90%, and a robust area under the receiver operating characteristic curve of 0.95, which compares favorably with experienced clinicians. Second, the LGB model, with an accuracy of 78% on EH prediction, outperformed the other 3 machine learning models. Finally, a feature importance analysis reveals a pivotal role of the specific pure-tone audiometry features that are essential for both MD diagnosis and EH prediction. Highlighted features include standard deviation and mean of the whole-frequency hearing, the peak of the audiogram, and hearing at low frequencies, notably at 250 Hz. CONCLUSION: An efficient machine learning model based on pure-tone audiometry features was produced to diagnose MD, which also showed the potential to predict the subtypes of EH. The innovative approach demonstrated a game-changing strategy for MD screening and promising cost-effective benefits for the health care enterprise.

Magnetic resonance imaging evaluation of cochlear and vestibular nerve calibre: a case-control study in Ménière's disease and endolymphatic hydrops.

PURPOSE: To compare the calibre of the cochlear (CN), superior vestibular (SVN) and inferior vestibular (IVN) nerves on magnetic resonance imaging (MRI), both between Ménière's Disease (MD) ears and clinical controls, and between inner ears with and without endolymphatic hydrops (EH) on MRI. METHODS: A retrospective case-control study evaluated patients undergoing MRI for suspected hydropic ear disease from 9/2017 to 8/2022. The CN, SVN, IVN and facial nerve (FN) diameters and cross-sectional areas (CSA) were measured on T2-weighted sequences whilst EH was evaluated on delayed post-gadolinium MRI. Absolute nerve calibre (and that relative to the FN) in unilateral definite MD ears (2015 Barany criteria) was compared to that in both asymptomatic contralateral ears and clinical control ears. Nerve calibre in ears with severe cochlear and vestibular EH was compared to ears without EH. t tests or Wilcoxon signed-rank test/Mann-Whitney U test were applied (p < 0.001). RESULTS: 173 patients (mean age 51.3 ± 15.1, 65 men) with 84 MD (62 unilateral) and 62 clinical control ears were studied. Absolute and relative CN dimensions were decreased in both MD ears (CSA and diameter) and the contralateral asymptomatic ears (CSA) when compared to clinical controls (p < 0.001). Absolute nerve dimensions were reduced in both severe vestibular EH (CN, IVN and SVN) and severe cochlear EH (CN) (p < 0.001), however this was not evident when adjusted according to facial nerve calibre. CONCLUSION: There is decreased absolute CN calibre in both symptomatic and asymptomatic MD ears as well as ears with severe cochlear and vestibular EH on MRI.

Predictive nomograms and an algorithm for managing patients with probable Meniere's disease.

PURPOSE: To explore the efficacy of diagnostic tests in accurately reclassifying patients initially diagnosed with probable Meniere's disease (MD) into either definite or non-MD categories. MATERIALS AND METHODS: A retrospective cohort study was conducted at a neurotology clinic between 1/2016 and 5/2022. Patients underwent a battery of tests, from which sensitivity, specificity, positive and negative predictive values, as well as positive and negative likelihood ratios, were calculated. Additionally, prediction nomograms were developed. RESULTS: Of the 69 patients, 25 (36.2 %) were initially classified as definite MD, 21 (30.4 %), probable MD, and 23 (33.4 %) non-MD. The mean follow-up was 3.5 years. The sensitivity of electrocochleography (ECochG) was the highest (92 %), with a negative likelihood ratio of 15 %. Magnetic resonance imaging (MRI) with MD-protocol had the highest specificity (100 %), with a positive likelihood ratio of 100 %. Videonystagmography, video head impulse test, and cervical vestibular-evoked myogenic potentials, had lower sensitivity and specificity. We were able to reclassify 18 (86 %) patients with probable MD: 12 (57 %) were diagnosed with definite MD, and 6 (29 %) were diagnosed with non-MD, consistent with their clinical course. CONCLUSIONS: The combination of ECochG and MRI with MD-protocol provides the most reliable approach to reclassify patients with Probable MD, ensuring a precise and accurate diagnosis. Vestibular tests express the functional status of the labyrinth and may not be reliable. Our findings provide valuable insights into clinical decision-making for patients with Probable MD and raise the consideration of additional diagnostic tests as supplementary to the existing clinical-only diagnosis criteria.

Efficacy of endolymphatic duct blockage in treating Ménière's disease. / å† æ·‹å·´ç®¡å¤¹é—­æœ¯æ²»ç–—æ¢ å°¼åŸƒç— çš„æ•ˆæžœ.

OBJECTIVES: Ménière's disease (MD) is an idiopathic inner ear disorder characterized by recurrent episodes of episodic rotational vertigo, fluctuating hearing loss, tinnitus, and a feeling of ear stuffiness. Endolymphatic sac (ES)-related surgery is used primarily in patients with MD who have failed to respond to pharmacologic therapy. Endolymphatic duct blockage (EDB) is a new procedure for the treatment of MD, and related clinical studies are still scarce. This study aims to investigate the dynamic changes in endolymphatic hydrops (EH) and the long-term surgical outcomes in MD patients undergoing EDB, and to evaluate the impact of different types of ES on the surgical efficacy. METHODS: A retrospective analysis was conducted on 33 patients with refractory MD who underwent EDB. Based on the morphology of their endolymphatic sacs, patients were divided into a normal-type group (n=14) and an atrophic-type group (n=19). The frequency of vertigo symptoms, hearing, vestibular function, and the dynamic changes of gadolinium-enhanced MRI of the inner ear were compared were compared before and after surgery between the 2 groups. RESULTS: Compared with the atrophic-type group, the patients in the normal-type group had a higher rate of complete vertigo control, better cochlear and vestibular function, and a lower endolymph to vestibule volume ratio (all P<0.05). In addition, 7 patients in the normal-type group were found to have reversal of EH, while no reversal of EH was detected in the atrophic-type group after surgery. CONCLUSIONS: The response to EDB treatment varies between normal and atrophic MD patients, suggesting that the 2 pathological types of endolymphatic sacs may have different underlying mechanisms of disease.

New non-contrast MRI of endolymphatic hydrops in Ménière's disease considering inversion time.

Objectives: Three-tesla MRI with gadolinium-based contrast agents is important in diagnosing Ménière's disease. However, contrast agents cannot be used in some patients. By using the compositional difference between the inner ear endolymph and perilymph, we performed basic and clinical research focused on potassium ions and protein to find the optimal parameters for visualizing endolymphatic hydrops on MRI without contrast. We then examined the relationship between severity stage and visualization rate of endolymphatic hydrops. Methods: In phantom experiments simulating the endolymph and perilymph, we explored MRI parameters that could be used to separate endolymph from perilymph by gradually changing the inversion time. We then used these parameters to perform both new non-contrast MRI and contrast MRI on the same day in Ménière's disease patients, and we compared the visualization rates of endolymphatic hydrops under the two modalities. Fifty patients were selected from 478 patients with Ménière's disease of different severity stages; 12 patients had asthma and allergy to contrast agents. Results: The higher the disease stage, the higher the endolymphatic hydrops visualization rate. The new non-contrast MRI gave significantly higher (p < .01) visualization rates of endolymphatic hydrops on the affected side in patients at Stage 3 or above than in Stages 1 and 2 combined. Conclusion: New non-contrast MRI with parameters focusing on the endolymph-perilymph difference in the density of protons surrounding the potassium ions and protein can produce images consistent with endolymphatic hydrops. We believe that this groundbreaking method will be useful for diagnosing Ménière's disease in patients. Evidence Level: Clinical studies are at evidence level 3 in non-randomized controlled trials.

Hydrops regression after vestibular denervation - longitudinal magnetic resonance study in patients with severe Meniere's disease treated with vestibular neurectomy.

OBJECTIVES: The aim was to evaluate endolymphatic hydrops in patients with severe Ménière's disease (MD) before and after vestibular neurectomy to verify if vestibular denervation results in hydrops regression. METHODS: Magnetic resonance imaging was performed after intravenous gadolinium injection in twenty patients with unilateral definite MD before and after the vestibular neurectomy. Clinical symptoms and audiovestibular tests were evaluated. Follow-up intervals ranged from 18 to 35 months after the surgery. RESULTS: Endolymphatic hydrops were visualized in all patients in the preoperative scans. After the vestibular neurectomy, all patients presented a complete resolution of vertigo episodes. Regression of the endolymphatic hydrops was observed in 35% and 15% of cases analyzing cochlea and vestibule, respectively. In 71.43% of patients with utricular herniation into the lateral semicircular canal, withdrawal of the hernia was visualized. Asymmetrical contrast enhancement in the cochlea regressed in 17.64% of cases. Analyzing all the parameters collectively, in 60% of patients, partial regression of at least one of the radiological signs was confirmed in the follow-up examination. No progression of the endolymphatic hydrops was visualized after the surgery in either the cochlea or the vestibule. CONCLUSIONS: Vestibular neurectomy is an effective treatment, eliminating vertigo attacks and improving the quality of life in patients with MD. Magnetic resonance imaging of the inner ear allows visualization of changes in endolymphatic hydrops degree after treatment. Regression of the endolymphatic hydrops after vestibular neurectomy suggests that vestibular denervation may effectively halt the progression of the endolymphatic space dilatation and result in hydrops regression.

Relationship Between Cochlear Lateral Wall Changes and Endolymphatic Hydrops in Otitis Media.

OBJECTIVES: Despite otitis media and various disease processes being associated with endolymphatic hydrops (EH), an exact explanation of the pathophysiology has yet to be reported. This study aimed to investigate the changes in the cochlear lateral wall structures and their potential correlation with the presence and severity of cochlear EH in acute and chronic otitis media cases. The investigations were conducted in both chinchilla animal model and human temporal bone specimens. METHODS: We studied a total of 15 chinchilla and 25 human temporal bones from our collection, which were categorized into acute otitis media, chronic otitis media (COM), and control groups. Through quantitative analysis, we measured the area of cochlear lateral wall structures and observed the presence and the degree of EH using light microscopy. RESULTS: No significant changes were determined in the area of the spiral ligament (p > 0.05) across the species. However, a significant (p < 0.05) decrease in the mean area of the stria vascularis in the basal turn was identified in COM groups compared to controls of both species. Chinchilla model additionally exhibited pathology extending to the lower mid turn. A negative correlation was found between the mean strial area and the severity of EH in both the animal model and human samples. CONCLUSIONS: COM associated with significant changes in the stria vascularis that may lead to significant increase in the degree of EH. The presented animal model exhibited parallel findings with human samples, suggesting its viability as a valuable model for future studies. LEVEL OF EVIDENCE: N/A Laryngoscope, 2024.

An unenhanced 3D-FLAIR sequence using long repetition time and constant flip angle to image endolymphatic hydrops.

OBJECTIVES: To evaluate a three-dimensional fluid-attenuated inversion recovery (3D-FLAIR) sequence using a long repetition time (TR) and constant flip angle (CFA) in differentiating between perilymph and endolymph in a phantom study, and unenhanced endolymphatic hydrops (EH) imaging in a patient study. METHODS: Three solutions in similar ion and protein concentrations with endolymph, perilymph, and cerebrospinal fluid were prepared for variable flip angle (VFA) 3D-FLAIR (TR 10,000 ms) and CFA (120°) 3D-FLAIR using different TR (10,000, 16,000, and 20,000 ms). Fifty-two patients with probable or definite Meniere's disease received unenhanced CFA (120°) 3D-FLAIR using a long TR (20,000 ms) and 4-h-delay enhanced CFA (120°) 3D-FLAIR (TR 16,000 ms). Image quality, signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) of them were compared. Agreement in the evaluation of the EH degree between them was analyzed. RESULTS: In the phantom study, CNRs between perilymphatic and endolymphatic samples of VFA 3D-FLAIR (TR 10,000 ms) and CFA 3D-FLAIR (TR 10,000, 16,000, and 20,000 ms) were 6.66 ± 1.30, 17.90 ± 2.76, 23.87 ± 3.09, and 28.22 ± 3.15 (p < 0.001). In patient study, average score (3.65 ± 0.48 vs. 4.19 ± 0.40), SNR (34.56 ± 9.80 vs. 51.40 ± 11.27), and CNR (30.66 ± 10.55 vs. 45.08 ± 12.27) of unenhanced 3D-FLAIR were lower than enhanced 3D-FLAIR (p < 0.001). Evaluations of the two sequences showed excellent agreement in the cochlear and vestibule (Kappa value: 0.898 and 0.909). CONCLUSIONS: The CFA 3D-FLAIR sequence using a long TR could be used in unenhanced EH imaging with high accuracy. CLINICAL RELEVANCE STATEMENT: Unenhanced imaging of endolymphatic hydrops is valuable in the diagnosis and follow-up of patients, especially those who cannot receive contrast-enhanced MRI. KEY POINTS: Ion and protein concentration differences can be utilized in differentiating endolymph and perilymph on MRI. Endolymphatic and perilymphatic samples could be differentiated in vitro on this 3D-FLAIR sequence. This unenhanced 3D-FLAIR sequence is in excellent agreement with the enhanced constant flip angle 3D-FLAIR sequence.

Temporal Bone Histopathology of Atypical Cogan Syndrome.

Cogan's syndrome is a rare disorder first clinically defined in 1945, characterized by nonsyphilitic interstitial keratitis and progressive audiovestibular symptoms. Later, patients with audiovestibular dysfunction and various types of inflammatory eye disease were classified as having atypical Cogan's syndrome. The etiology and pathogenesis of Cogan's syndrome remain largely unknown. Here, we report a case of atypical Cogan's syndrome with a histological assessment of the temporal bone during the acute disease period. Temporal bone histology was compared to age- and gender-matched normal control, and our findings revealed endolymphatic hydrops and degenerative changes in various parts of the inner ear. Laryngoscope, 2024.

Efficacy of 100 hz sound stimulation on saccular dysfunction in meniere's disease.

BACKGROUND: Although various medical remedies have been attempted to alleviate the symptoms of Meniere's disease (MD), the risk-benefit ratios of these various treatments remain debatable. OBJECTIVE: We investigated the efficacy of sound stimulation of 100 Hz for treating vestibular dysfunction in patients with Meniere's disease (MD). MATERIALS AND METHODS: Patients with definitive MD with intractable vestibular symptoms and endolymphatic hydrops (EH) in the inner ear were evaluated. The experimental group received sound stimulation of 75 dB at a frequency of 100 Hz for 5 min, and the control group received sound stimulation of 75 dB at a frequency of 250 Hz for 5 min. Cervical vestibular-evoked myogenic potentials (cVEMPs) were measured before and after each sound stimulation, and the results of the clinical tests were compared between the two patient groups. RESULTS: Significant increases in cVEMP amplitudes were observed after sound stimulation of 100 Hz in ears with vestibular endolymphatic hydrops, although no such improvement was observed in the control group. CONCLUSION: Sound stimulation of 75 dB at a frequency of 100 Hz leads to improvement in cVEMP amplitude in patients with definitive MD. Adequate sound stimulation might be a new method for treating vestibular dysfunction associated with MD.

Potential Application of Hydrops MR Imaging: A Systematic Review.

BACKGROUND: Diagnostic dilemma between clinical Meniere's disease and radiological endolymphatic hydrops (EH) has emerged since the introduction of hydrops magnetic resonance imaging (MRI). The aim of this study is to explore the potential application of hydrops MRI on diagnosing the EH. METHODS: This review was developed from peer-reviewed articles published in those journals listed on journal of citation reports. The MEDLINE database of the US National Library of Medicine, Scopus, and Google Scholar were used to collect articles based on the guidelines (PRISMA 2020 statement) for reporting reviews. RESULTS: Initially, 470 articles were retrieved from 1983 to 2023, and 80 relevant articles were ultimately selected. The sensitivity (69%-92%) and specificity (78%-96%) values varied from each laboratory for detecting EH via hydrops MRI, probably due to candidate selection and the grading system employed. CONCLUSION: The application of hydrops MRI allows (1) differentiation between EH and sudden sensorineural hearing loss; (2) determination of the affected side of EH; and (3) confirmation of the diagnosis of EH concomitant with other disorders. Notably, not all differentials for EH can be visualized on MR images. One of the existing gaps to be filled is that updated hydrops MRI fails to identify distortion, that is, rupture, collapse, fistula, or fibrosis of the inner ear compartments, akin to what histopathological evidence can demonstrate. Hence, enhanced ultrahigh resolution of hydrops MRI is required for demonstrating fine structures of the inner ear compartments in the future.

Sudden Sensorineural Hearing Loss in Patients Aged from 15 to 40 Years.

Objectives: The purpose of this study was to investigate the hearing characteristics and causes of sudden sensorineural hearing loss (SSNHL) in patients aged from 15 to 40 years, focusing on audiological outcomes one year after the diagnosis. Methods: The medical records of individuals with SSNHL who were referred to our tertiary-level audiologic center were reviewed. All patients had undergone comprehensive diagnostic evaluations, including high-resolution 3D-FLAIR delayed magnetic resonance imaging (MRI), cone beam computed tomography (CBCT), and screening for coagulation, infectious, and autoimmune diseases. Results: Overall, 56 patients (mean age 28.1 ± 7.6 years) were included in the study. The hearing threshold in the affected ear improved significantly from 56.0 ± 18.0 dB at the diagnosis to 46.9 ± 22.3 dB after one year (p = 0.02). The degree of hearing loss, audiometric configurations, hearing improvements, and adherence to hearing treatments showed considerable variability among patients. Aural fullness, tinnitus, and hyperacusis were the predominant symptoms associated with SSNHL, and their prevalence decreased significantly over time. The diagnostic protocol led to the identification of the specific cause of SSNHL in 75% (42/56) of patients. The known etiology was found to be otological (39.3%), infectious (21.4%), autoimmune (7.1%), vascular (5.4%), or neoplastic (1.8%). In particular, Menière's disease (n = 12), isolated cochlear endolymphatic hydrops (n = 6), HSV-1 (n = 5), and EBV (n = 4) infections were the most frequent causes of SSNHL. Conclusions: The identification of the specific etiology of SSNHL may facilitate a more personalized approach to management and treatment.