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.

Comparative analysis of vestibular endolymphatic hydrops grading methods and hearing loss in Ménière's disease: a retrospective MRI study using 3D-real inversion recovery sequence.

PURPOSE: To compare the correlation between different grading methods of vestibular endolymphatic hydrops (EH) and the severity of hearing loss in Ménière's disease (MD), and evaluate the diagnostic value of these methods in diagnosing MD. METHODS: This retrospective study included 30 patients diagnosed with MD from June 2021 to August 2023. All patients underwent inner ear MR gadolinium-enhanced imaging using three-dimensional (3D)-real inversion recovery sequences and pure-tone audiometry. The EH levels were independently evaluated according to the classification methods outlined by Nakashima et al. (Acta Otolaryngol Suppl 5-8, 2009. https://doi.org/10.1080/00016480902729827 ) (M1), Fang et al. (J Laryngol Otol 126:454-459, 2012. https://doi.org/10.1017/S0022215112000060 ) (M2), Barath et al. (Am J Neuroradiol 35:1387-1392, 2014. https://doi.org/10.3174/ajnr.A3856 ), (M3), Liu et al. (Front Surg 9:874971, 2022. https://doi.org/10.3389/fsurg.2022.874971 ), (M4), and Bernaerts et al. (Neuroradiology 61:421-429, 2019. https://doi.org/10.1007/s00234-019-02155-7 ) (M5), with a subsequent comparison of interobserver agreement. After achieving a consensus, an analysis was performed to explore the correlations between vestibular EH grading using different methods, the average hearing thresholds at low-mid, high-, and full frequencies and clinical stages. The diagnostic capabilities of these methods for MD were then compared. RESULTS: The interobserver consistency of M2-M5 was superior to that of M1. The EH grading based on M4 showed a significant correlation with the average hearing thresholds at low-mid, high-, and full frequencies and clinical stages. M1, M2, M3, and M5 correlated with some parameters. A receiver operating characteristic curve analysis indicated that M5 significantly outperformed M1, M2, M3, and M4 in terms of diagnostic efficiency for MD. CONCLUSION: M4 showed the strongest correlation with the degree of hearing loss in patients with MD, whereas M5 showed the highest diagnostic performance.

The value of gadolinium-enhanced MRI in predicting the development of sudden hearing loss into Ménière's disease.

OBJECTIVE: To compare the clinical features of sudden hearing loss (SHL) in patients with and without endolymphatic hydrops (EH), and to investigate the association between SHL with EH and Ménière's disease (MD). METHODS: The clinical data of 63 SHL patients with first symptoms were evaluated retrospectively. Patients were separated into two groups based on the results of gadolinium-enhanced magnetic resonance imaging: EH and non-EH groups. Independent sample t-test and U-test were used to compare groups for continuous variables, and the chi-squared test, corrected chi-squared test and Bonferroni correction test were used to compare groups for binary and ordinal variables. The binary logistic regression model was utilised for univariate and multivariate analysis of follow-up patient prognosis. RESULTS: The EH and non-EH groups contained 32 and 31 patients, respectively. The EH group had a higher prevalence of low-tone descending hearing loss. Fifty-one patients were followed for more than 2 years. In the EH group, 11 and 15 patients were diagnosed with sudden sensorineural hearing loss (SSNHL) and MD, respectively, while in the non-EH group, 24 patients were diagnosed with SSNHL and only one with MD. EH, low-tone descending hearing loss and vertigo were risk factors for the diagnosis of MD in a subgroup univariate regression analysis of patients experiencing SHL. EH was found to be a risk factor for the progression of SHL into MD in a multifactor regression analysis. CONCLUSIONS: Patients with SHL who have EH are more likely to present with low-tone descending hearing loss. EH is a risk factor for the subsequent development of MD.

Blood-labyrinth barrier breakdown in Meniere's disease.

OBJECTIVE: We compared the signal intensity ratio (SIR) of the cochlear basal turn between Meniere's disease and healthy controls to investigate potential damage of the blood-labyrinth barrier in Meniere's disease. METHODS: Thirty patients diagnosed with unilateral definite Meniere's disease and 24 healthy controls were enrolled. 3D-FLAIR scan was conducted to assess the grades of endolymphatic hydrops in Meniere's patients while measuring the SIR of cochlear basal turns in both groups. The differences of bilateral SIR between Meniere's disease and healthy control were compared, and the correlation between the SIR on affected ear in Meniere's disease and the grades of cochlear and vestibular hydrops were analyzed. RESULTS: SIR of affected ear in Meniere's disease exhibited significant increase compared to that of unaffected ear. No significant difference was observed in SIR between the two ears in the healthy control. Furthermore, the SIR of unaffected side in Meniere's disease was higher than that of both ears in healthy controls. The SIR in affected ear of Meniere's disease exhibited positive correlation with hydrops in both cochlea and vestibula. CONCLUSION: The permeability of blood-labyrinth barrier is increased in Meniere's disease, in combination with the typical criteria of Meniere's disease it may be a good biological marker. Destruction of blood-labyrinth barrier may be one of the causes of endolymphatic hydrops in Meniere's disease.

Impact of endolymphatic hydrops on the function of the horizontal canal during caloric stimulation in Ménière's disease.

PURPOSE: When a dizzy patient with episodic vertigo has an abnormal caloric and a normal video head impulse test (vHIT), this caloric-vHIT dissociation provides vital information for a diagnosis of Ménière's disease (MD). Endolymphatic hydrops (EH), a histological marker of MD, is hypothesized to be involved in the caloric-vHIT dissociation in MD through hydropic duct distension of the horizontal semicircular canal (SC). This study was designed to determine the impact of EH on the function of horizontal SC during caloric stimulation. METHODS: Caloric test and vHIT were used to evaluate the function of horizontal SC every six months, annual magnetic resonance imaging (MRI) was used to evaluate the degree of EH size in the vestibule, and monthly vertigo and hearing evaluation was done for 12 months. EH shrinkage was defined as the size change of vestibular EH from significant to none. RESULTS: Among 133 MD patients evaluated for eligibility, 67 patients with caloric-vHIT dissociation entered the study. Fifteen participants had EH shrinkage (G-I), while 52 participants had no remarkable EH change (G-II). Average values (IQR) of the maximum slow phase velocity in G-I and G-II were 29.6 (13.0-34.0) and 25.9 (17.3-31.3), respectively, at baseline, 26.1 (9.0-38.0) and 23.6 (18.0-28.3) at 12 months. Two-factor repeated-measures ANOVA showed no significant differences between the groups (P = 0.486). The values of vestibulo-ocular reflex gain of the horizontal SC in G-I and G-II remained above 0.8 during the study period. CONCLUSIONS: EH detected by MRI shows limited correlation with caloric stimulation results.

Evaluation of changes in endolymphatic hydrops volume after medical treatments for Meniere's disease using 3D magnetic resonance imaging.

OBJECTIVE: To elucidate the relationship between vertigo and EH volume after medical treatment, we investigated changes in endolymphatic hydrops (EH) volume using inner ear magnetic resonance imaging (ieMRI) in relation to clinical results for vertigo and hearing after administration of the anti-vertiginous medications betahistine, adenosine triphosphate (ATP), isosorbide (ISO), and saireito (SAI) for Meniere's disease (MD). METHODS: We retrospectively enrolled 202 consecutive patients diagnosed with unilateral MD from 2015 to 2021 and assigned them to four groups: Group I (G-I), symptomatic oral medication with betahistine only (CONT); Group II (G-II), inner ear vasoactive oral medication (ATP); Group III (G-III), osmotic diuretic oral medication (ISO); and Group IV (G-IV), kampo oral medication (SAI). In total, 172 patients completed the planned one-year-follow-up, which included the assessment of vertigo frequency, hearing improvement, and changes in EH using ieMRI (G-I, n=40; G-II, n=42; G-III, n=44; G-IV, n=46). We constructed 3D MRI images semi-automatically and fused the 3D images of the total fluid space (TFS) of the inner ear and endolymphatic space (ELS). After fusing the images, we calculated the volume ratios of the TFS and ELS (ELS ratios). RESULTS: One year after treatment, vertigo was controlled with zero episodes per month in 57.5% (23/40) of patients in G-I, 78.6% (33/42) in G-II, 81.8% (36/44) in G-III, and 82.6% (38/46) in G-IV (statistical significance: G-I 10 dB in 5.0% (2/40) of patients in G-I, 16.7% (7/42) in G-II, 18.2% (8/44) in G-III, and 21.7% (10/46) in G-IV (statistical significance: G-I=G-II=G-III=G-IV). ELS ratios were significantly reduced after treatment only in the vestibule for G-II, G-III, and G-IV when compared with G-I. Especially among patients with complete control of vertigo after treatment, ELS ratios were significantly reduced after treatment in the vestibule and total inner ear for G-II; in the cochlea, vestibule, and total inner ear for G-III; and in the cochlea, vestibule, and total inner ear for G-IV compared with G-I. However, there were no significant findings in the relationship between hearing results and changes in ELS ratios. CONCLUSION: These results indicate that daily administration of anti-vertiginous medications including ATP, ISO, and SAI could be an effective treatment option for patients with MD at an early stage before it becomes intractable. Treatments to reduce EH might offer better control of vertigo rather than improve hearing.

Endolymphatic hydrops imaging and correlation with clinical characteristics, audiovestibular function and mental impairment in patients with Meniere's disease.

PURPOSE: MR imaging was used to visualize the vestibular and cochlear endolymphatic hydrops in patients with Meniere's disease (MD). The relationship between the degree of hydrops and clinical characteristics, audiovestibular function, anxiety and depression state in MD patients. METHODS: 70 patients with definitely or probably unilateral Meniere's disease received bilateral intratympanic gadolinium administration and MR scanning. The degree of bilateral vestibular and cochlea hydrops were analyzed and evaluated by three-dimensional real inversion recovery (3D-real IR) sequence, and the correlation between the grades of endolymphatic hydrops (EH) and disease course, vertigo grading assessment, the duration of vertigo, hearing loss level, caloric test, vestibular myogenic evoked potential (VEMP), electrocochleogram (EcoG), vertigo disability scale (physical, emotional, functional), anxiety and depression scale were studied. RESULTS: It was found that the vestibule and cochlea EH of the affected and the contralateral ear had different degrees of hydrops and there was no statistical difference between the left and right vestibules. The degree of vestibule EH (V-EH) was significantly positively correlated with the degree of cochlear EH (C-EH). C-EH and hearing loss level were positively correlated with EcoG. There was positive correlation between vestibular EH and hearing loss level, VEMP, caloric test, disease course or vertigo duration. There was a negative relationship between Dizziness Handicap Inventory (Emotion) (DHI(E)) and VEMP. Self-rating Anxiety Scale (SAS) and Self-rating Depression Scale (SDS) scores were positive correlated with DHI(E) and DHI total scores in MD patients. CONCLUSION: Endolymph-enhancing MRI was used as an important imaging method for the diagnosis of labyrinthine hydrops in Meniere's disease. There were certain correlation between EH and the degree of vertigo attack, hearing loss level, vestibular function, and further changes in anxiety and depression emotion.

Temporal changes in endolymphatic hydrops on MRI with or without intervention: A systematic review.

OBJECTIVE: The pathophysiology of Meniere's Disease (MD) involves endolymphatic hydrops (ELH) of the inner ear. Magnetic Resonance Imaging (MRI) has been shown to detect ELH, but changes in ELH have been poorly described using this modality. Our objective was to review MRI-measured changes in ELH over time and after medical and/or surgical intervention in patients with MD. We secondarily aim to associate changes in ELH with changes in MD symptomatology. DATABASES REVIEWED: Medline, Web of Science, and Embase databases. METHODS: A systematic review of articles was performed to identify studies utilizing MRI to measure ELH changes over time, and after medical or surgical treatment. Articles on non-human subjects and without direct measurement of ELH were excluded. RESULTS: Of 532 studies identified, 12 were included, involving 170 patients (mean age 56.3 years). Ten studies were prospective; two were retrospective. Five studies strictly utilized medical means of intervention, four utilized surgical treatments, one utilized both, and two observed temporal changes without treatment. Across all interventions, 72.1 % of patients exhibited the same or worsening ELH on imaging. In studies reporting vertigo outcomes, 95.9 % of patients exhibited improvement after the treatment period. CONCLUSION: Medical and surgical interventions often yield symptomatic relief of vertigo in MD patients despite stable or increasing ELH volume. MRI may have greater clinical utility in diagnosing ELH as opposed to assessing treatment response.

Assessing the usefulness of inner ear contrast-enhanced magnetic resonance imaging and pure-tone audiometry in estimating the prognostic value of hearing improvement in patients with definite Meniere's disease.

PURPOSE: Meniere's disease (MD) is characterized by combined cochlear and vestibular symptoms. However, its underlying cause remains unclear, with low-to-mid-tone hearing impairment being predominantly reported. Moreover, predicting hearing improvement after disease onset is not possible. This study aimed to assess whether hearing improvement in patients with definite MD (DMD) could be predicted using inner ear contrast magnetic resonance imaging (IEC-MRI) and pure-tone audiometry (PTA) at disease attack. MATERIALS AND METHODS: Between April 2020 and March 2022, seven outpatients with DMD were enrolled based on the Bárány Society DMD criteria. The patients were divided into two groups: low-tone hearing loss (LTL) group and low-to-mid-tone hearing loss (LMTL) group. Hearing improvement rates as well as the possible inter-relation between endolymphatic hydrops and hearing improvement were evaluated. RESULTS: Endolymphatic hydrops was found in two of four LTL cases. One of three LMTL cases had prominent lymphedema. All patients with LTL but only one patient with LMTL had hearing improvement. Endolymphatic hydrops was not found to be correlated with hearing improvement. CONCLUSIONS: Estimating hearing improvement in patients with DMD using IEC-MRI was not possible. However, PTA showed better hearing prognosis in LTL than in LMTL. Therefore, estimating hearing improvement using PTA was possible at disease attack.

Endolymphatic Hydrops in the Setting of Vestibular Schwannoma: A Temporal Bone Study.

HYPOTHESIS: Vestibular schwannoma (VS) may be associated with endolymphatic hydrops (EH). EH may account for symptomatology in a subset of patients with VS. BACKGROUND: Presenting symptoms of VS and EH overlap, and MRI evaluation of the membranous labyrinth in some patients with VS demonstrates EH. The aim of the current study is to evaluate whether EH is present in temporal bones of patients with VS. METHODS: The NIDCD and House Temporal Bone Laboratory at UCLA Eccles database was queried for the diagnosis of "acoustic neuroma." Exclusion criteria included concomitant ear disease and surgery. Temporal bones were analyzed for EH of the basal, middle, and apical turns and vestibule. Premortem audiometric and clinical data were gathered. RESULTS: Of 43 human temporal bones with VS, 6 met inclusion criteria. All temporal bones demonstrated VS that was undisturbed by surgery. Three of six demonstrated EH of at least one cochlear turn as well as vestibular hydrops. Three patients had severe to profound hearing loss. One patient carried a diagnosis of Menière's disease. CONCLUSIONS: EH is demonstrated in the setting of VS in human temporal bones. EH may be one mechanism of hearing loss and dizziness in patients with VS. PROFESSIONAL PRACTICE GAP AND EDUCATIONAL NEED: The underlying mechanisms of symptoms of VS may be multifactorial. The association of EH in some patients with VS would modify our clinical approach to management. LEARNING OBJECTIVE: To discover if EH may be associated with VS. DESIRED RESULT: To broaden understanding of pathophysiologic mechanisms in patients with VS. LEVEL OF EVIDENCE: Level IVIRB Approved: UCLA IRB No. 10-001449.

Limitation of updated MR images on the vestibular hydrops in Meniere's disease.

PURPOSE: This study adopted the cervical and ocular vestibular-evoked myogenic potential (cVEMP and oVEMP) tests in Meniere's disease (MD) patients to correlate them with vestibular endolymphatic hydrops (EH) on MR images. METHODS: A total of 25 patients with unilateral definite MD identified by positive cochlear hydrops on MR images were enrolled. All patients underwent audiometry, cVEMP test and oVEMP test, followed by MR imaging for confirmation. RESULTS: A significantly declining sequence of abnormality rates in MD patients was identified from the audiometry (92%), cVEMP test (52%) to the oVEMP test (40%), which was consistent with a significantly decreasing order of prevalence of EH on MR images running from the cochlea (100%), saccule (56%) to the utricle (52%). The cVEMP test for detecting the saccular hydrops revealed a sensitivity of 62%, while the oVEMP test for assessing the utricular hydrops showed a sensitivity of 70%. However, correlating VEMP results with vestibular hydrops did not show any significant relationship. In addition, mean hearing level (MHL) at four frequencies (500, 1000, 2000, and 3000 Hz) of Grade I cochlear hydrops (51 ± 19 dB) did not significantly differ from Grade II cochlear hydrops (53 ± 19 dB). CONCLUSION: Limitations of the updated MR imaging for visualizing the hydrops comprised: (1) failure to correlate vestibular hydrops with VEMP results, and (2) failure to correlate grade of cochlear hydrops with MHL. The reason is probably because updated MR imaging fails to identify distorted contour of the cochlea/utricle/saccule. Further advanced technique using ultrahigh resolution of fine structures in the inner ear compartments is essential to promote a wider use of MR imaging.

Systematic review of the diagnostic value of hydrops MRI in relation to audiovestibular function tests (electrocochleography, cervical vestibular evoked myogenic potential and caloric test).

The objective of this systematic review is to compare the diagnostic value of endolymphatic hydrops (EH) magnetic resonance imaging (MRI) with audiovestibular function tests, including electro cochleography (ECochG), cervical vestibular evoked myogenic potential (cVEMP) and caloric tests for the diagnosis of definite Meniere's disease (DMD). An electronic search was performed in the PubMed, Embase and Cochrane databases in August 2022. Original studies which reported the efficacy of gadolinium MRI for diagnosis of DMD were compared with ECochG, cVEMP and caloric tests from 2007 to 2022 published in English. Two reviewers extracted the methodology and results of MRI and functional tests, assessing them independently. A modified version of the Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) was used for the assessment of the quality and the risk of bias of each study. The proportion of DMD cases diagnosed by MRI hydrops vs corresponding functional tests were calculated and the relationship between MRI and functional tests were evaluated using the Cohen's Kappa test. Concerning the MRI, the proportion diagnostic of DMD was 0.67 by cochlear EH and 0.80-0.82 by vestibular EH. Regarding the functional test, the propotiojn diagnostic of DMD was 0.48 by ECochG, 0.76 by cVEMP and 0.65 by caloric test. The findings of this systematic review were that the vestibular EH on imaging most effectively assisted in diagnosing DMD. Among the functional tests, cVEMP was the second most effective test. The agreement between imaging and cVEMP was moderate (0.44), indicating a gap between the patients identified by the imaging and functional tests based on the relatively small number of patients.

Is there progression of endolymphatic hydrops in Ménière's disease? Longitudinal magnetic resonance study.

BACKGROUND: Endolymphatic hydrops (EH) is universal in Ménière´s disease (MD). Given its chronic course, with variable interval before complete clinical picture is installed, it seems relevant to understand the progression of vestibular EH and hemato-perilymphatic barrier disruption in patients with MD and monosymptomatic presentations. METHODS: 239 consecutive patients were referred to us with suspected hydropic ear disease. 50 individuals accepted to participate in this study-final longitudinal sample included 24 patients (7 D1, 7 D2, 10 D3). Control group included ten patients. At recruitment, a clinical and MRI re-evaluation was done (3T, intravenous technique) (MR2) and 2 years after MRI was repeated (MR3). Previous MRI (MRI1) were retrospectively evaluated. Patients were classified as definite (D1), possible (D2) and atypical (D3-monosymptomatic) MD. Control group included non-typical symptoms (C2/C3) and 6 asymptomatic (C1). Vestibular endolymphatic ratio (vER) and grading, presence/absence of cochlear EH, asymmetry of cochlear perilymphatic enhancement, and rate of progression of vER were assessed by two independent neuroradiologists and compared between patient and control groups (index ear). RESULTS: EH was universal and pronounced in D1 and remained stable. vER progression was more variable and higher in some D3 patients (index ear worse) and in D2 (non-index), although this observation was not statistically significant. CONCLUSIONS: Considering that many probable and monosymptomatic presentations progress years later into definite MD and given the bilateral tendency of the disease, these findings may indicate that there is an initial accelerated worsening of EH in initial stages of the disease. These data should be confirmed with controlled and larger sample studies.

[Interpretation of consensus on MRI of endolymphatic hydrops in patients with suspected hydropic ear disease and domestic research progress].

Endolymphatic hydrops（EH） is considered the histological hallmark of Meniere's disease. Visualization of EH has been achieved by special sequences of inner ear magnetic resonance imaging（MRI） with gadolinium-based contrast-agent via intravenous or intratympanic administration. Although it has been applied for more than ten years since 2007, a unified view on this technique has not yet been achieved. In 2022, Yang Jun and Duan Maoli et al led the organization to write the international expert consensus on MRI of EH. This article interprets the main contents and reports related progress.

Post-irradiation endolymphatic hydrops vs. post-irradiation sudden deafness.

BACKGROUND: Increasing numbers of acute sensorineural hearing loss (SNHL) are recently experienced in irradiated nasopharyngeal carcinoma (NPC) survivors. AIM: This study adopted MR imaging to differentiate between post-irradiation sudden deafness (PISD) and post-irradiation endolymphatic hydrops (PIEH) in long-term NPC survivors with acute SNHL. METHODS: From 2012 to 2021, consecutive 10 irradiated NPC survivors with acute SNHL were enrolled. All patients underwent an inner ear test battery and MR imaging using HYDROPS-Mi2 technique. Six patients (11 ears) with positive cochlear hydrops on MR images were diagnosed as PIEH, while another 4 patients (4 ears) without cochlear hydrops on MR images were referred to PISD. RESULTS: The interval from the onset of NPC to acute SNHL did not significantly differ between the PIEH (10 ± 6 years) and PISD (8 ± 2 years). No significant difference was found between the two disorders from any of the symptomatic, radiotherapeutic, audiological, or vestibular perspective. Interestingly, most (5/6) patients with PIEH had bilateral involvement, while all (4/4) patients with PISD showed unilateral affliction. A significantly declining sequence of abnormality rates in the inner ear test battery was noted in the PIEH patients, running from the audiometry (100%), cervical vestibular-evoked myogenic potential (VEMP) test (100%), ocular VEMP test (73%), to the caloric test (36%). However, such declining trend was not observed in patients with PISD. CONCLUSION: When facing an NPC survivor who had acute SNHL over a prolonged period after irradiation, MR imaging using HYDROPS-Mi2 technique should be performed to differentiate the PIEH from the PISD, since both disorders have various treatment modalities and hearing outcome.

Prevalence of Endolymphatic Hydrops in Cochlear Implant Candidates with Idiopathic Profound Sensorineural Hearing Loss.

OBJECTIVE: To determine the prevalence of endolymphatic hydrops (EH) in cochlear implant (CI) candidates with idiopathic profound sensorineural hearing loss (SNHL) and its influence on the preservation of audiovestibular function after cochlear implantation. STUDY DESIGN: Prospective case series. SETTING: Tertiary referral center. PATIENTS: CI candidates with idiopathic progressive SNHL, but without classic EH-associated symptoms. INTERVENTIONS: Delayed intravenous gadolinium-enhanced inner ear fluid-attenuated inversion recovery magnetic resonance imaging as well as pure-tone audiograms, video head impulse tests, and vestibular evoked myogenic potentials before and 4 weeks after cochlear implantation. MAIN OUTCOME MEASURES: Prevalence of EH before cochlear implantation, audiovestibular function before and after surgery in hydropic and nonhydropic ears. RESULTS: Thirty-two ears in 16 CI candidates were included. Nine ears (28%) with EH were detected. Although preoperative hearing thresholds, utricular function, and semicircular canal function were not different between the two groups, saccular function was reduced in hydropic ears. Ten subjects received a unilateral CI. Of these, 3 (30%) showed EH on the implanted side. There was no difference regarding postoperative hearing loss between the two groups, but the results point toward a higher vulnerability of hydropic ears with respect to loss of otolith function after cochlear implantation. CONCLUSIONS: This is the first study showing that EH can be assumed in about one third of CI candidates with idiopathic profound SNHL, but no classic EH-associated symptoms. Preliminary results suggest that EH has no influence on the preservation of cochlear function but could be a risk factor for loss of otolith function after cochlear implantation.

Endolymphatic hydrops in the unaffected ear of patients with unilateral Ménière's disease.

PURPOSE: Current studies show that frequency tuning modification is a good marker for the detection of endolymphatic hydrops (EH) employing magnetic resonance imaging (MRI) in patients with Ménière's disease (MD). The purpose of the present study is to analyze the auditory and vestibular function with audiometric and vestibular-evoked myogenic potentials (VEMP) responses, respectively, in both the affected and unaffected ears of patients with unilateral MD using MRI as diagnostic support for the degree of EH. METHODS: We retrospectively reviewed the medical records of 76 consecutive patients with unilateral definite MD (age 55 (28-75); 39 women, 37 men). MRI was used through intravenous gadolinium administration, audiometry, and VEMPs. Functional tests were performed up to a week after the MRI. All were followed up one year after imaging utilizing clinical, auditory, and vestibular testing to rule out bilateral involvement. RESULTS: In the unaffected ear, the mean pure-tone average is normal even in cases with hydrops and, for a similar severity of hydrops is significantly lower than in the affected ear. Significant differences for the amplitude of the response at 0.5 kHz, at 1 kHz between the affected and unaffected ears were found to be lower in the affected ears. The relative amplitude ratio (1 Kz-0.5 kHz) was significantly lower in the affected ear and in the case of the oVEMP response depends on the degree of EH. The response in the unaffected ear was not modified by the presence or the degree of hydrops. CONCLUSION: In the unaffected ear, hydrops is not associated with hearing deterioration. For a similar degree of hydrops, hearing loss is significantly greater in the affected ear. The endolymphatic hydrops in the vestibule induces a frequency bias in the VEMP response only in the affected ear and not in the unaffected ear. Because of these findings we consider that hydrops does not represent an active disorder in the unaffected ear.

Clinical high-resolution imaging and grading of endolymphatic hydrops in Hydropic Ear Disease at 1.5 T using the two-slice grading for vestibular endolymphatic hydrops in less than 10 min.

BACKGROUND: Hydropic Ear Disease (Menière) is one of the most common inner ear disorders and one of the most common causes of vertigo attacks. The underlying pathology is a distension of the endolymphatic space of the inner ear, termed endolymphatic hydrops. However, the unequivocal morphologic confirmation of ELH has been restricted to post-mortem histologic analysis until 2007, when the first clinical MR imaging report demonstrated ELH in living patients with Menière's disease at 3 T combined with intratympanic application of contrast. Imaging techniques have since then evolved further. However, a high magnetic field strength of 3 T has consistently been mandatory for reliable clinical imaging of ELH. This limitation has significantly prevented ELH imaging from being widely available across different health care systems around the world. With the aim of filling this gap, in the present study, we aim to describe the feasibility of ELH imaging at 1.5 T in clinical practice and to develop a dedicated grading system for cochlear and vestibular ELH for MR imaging at 1.5 T. METHODS: In this retrospective study, we examined 30 patients with suspected hydropic ear disease undergoing diagnostic MR imaging. Contrast agent was diluted eightfold in saline solution and unilaterally applied by intratympanic injection as described previously. MRI scanning was performed using a 16-channel head coil on a 1.5 T Achieva Philips Medical Systems Scanner using a 3D FLAIR sequence. For the cochlea, a 3-stage grading was developed. For the vestibulum, a 4-stage grading based on two axial slices was developed by analysing both the superior and the inferior part of the vestibulum. The presence of hydropic herniation of the endolymphatic space into the posterior crus of the horizontal semicircular canal was evaluated. RESULTS: In all 30 patients, the perilymphatic fluid spaces of the inner ear showed clear and high signal intensity, while the endolymphatic space was not enhanced. In all patients, the vestibular endolymphatic space could be clearly delineated and differentiated from the perilymphatic space. Analysis of the cochlear endolymphatic space revealed no evidence of ELH in 7 patients, a grade 1 cochlear ELH in 11 patients and a grade 2 cochlear ELH in 12 patients. Analysis of the vestibular endoylmphatic space revealed no evidence of ELH in 8 patients, a grade 1 vestibular ELH in 5 patients, a grade 2 vestibular ELH in 9 patients and a grade 3 vestibular ELH in 8 patients. Three patients showed a clear hydropic herniation of the vestibular endolymphatic space into the posterior non-ampullated crus of the horizontal SCC. CONCLUSION: In summary, the findings presented in this study offer an easy, reliable and universally available technique of ELH imaging for diagnostic management of patients with suspected Hydropic Ear Disease.

Changes in endolymphatic hydrops after vestibular neurectomy observed in magnetic resonance imaging - A pilot study.

OBJECTIVES: The aim was to evaluate endolymphatic hydrops in patients with Ménière's disease before and after vestibular neurectomy to verify if the endolymphatic space dilatation, observed in magnetic resonance imaging, regressed within several months after surgery. METHODS: Magnetic resonance imaging was performed after intravenous gadolinium injection in four patients with unilateral definite Ménière's disease before and eight months after vestibular neurectomy. Clinical symptoms, audiovestibular tests, and endolymphatic hydrops in magnetic resonance imaging were evaluated. RESULTS: Endolymphatic hydrops was visualized in preoperative magnetic resonance imaging in three out of four analyzed patients. In the remaining one, an asymmetrical contrast enhancement in the affected ear was found. After the vestibular neurectomy, all four patients presented a complete resolution of vertigo episodes and improved functional level. Significant postoperative hearing deterioration was found in two patients. In the follow-up magnetic resonance imaging, no reduction of the endolymphatic hydrops was visualized. A reduction of asymmetrical contrast enhancement in one patient was found. CONCLUSIONS: Magnetic resonance imaging of the inner ear is a helpful diagnostic tool for Menière's disease. Vestibular neurectomy is an effective treatment for intractable vertigo; however, there is no endolymphatic hydrops regression evidence within several months after the surgery. Therefore, further studies with a long follow-up period and repeated magnetic resonance imaging are needed to assess the vestibular neurectomy's impact on endolymphatic hydrops. Nevertheless, magnetic resonance imaging supports the clinical diagnosis of Ménière's disease and may help understand its pathophysiology.