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.

MRI can help differentiate Ménière's disease from other menieriform diseases.

It is difficult to distinguish other pathologies mimicking Ménière's disease (MD) clinically. This study aims to investigate the differences of imaging findings and features between MD and other menieriform diseases via intravenous gadolinium-enhanced magnetic resonance imaging (MRI). 426 patients with menieriform symptoms, including MD, vestibular migraine (VM), and vestibular schwannoma (VS), underwent 3D-FLAIR and 3D-T2WI MRI 6 h after the intravenous gadolinium injection. MR images were analyzed for inner ear morphology, perilymphatic enhancement (PE), EH and other abnormalities. EH was observed at a higher rate in MD patients (85.71%) than patients with other menieriform diseases (VM group = 14.75%, VS group = 37.50%). The prevalence of unilateral EH as well as both cochlear and vestibular EH showed significant differences between MD and VM groups. The prevalence of cochlear EH (I and II) and vestibular EH (II and III) was different between MD and VM groups. The prevalence of PE was higher in MD than VM group. The degrees of cochlear and vestibular hydrops were higher in the definite than probable MD group (P < 0.05). Using these imaging features, MRI can be used to help differentiate MD from other menieriform diseases.

Endolymphatic Duct Blockage as a Surgical Treatment Option for Ménière's Disease.

Endolymphatic duct blockage is a relatively new treatment option for Ménière's disease, aiming to reduce vertigo attacks while sparing hearing and equilibrium. After a regular mastoidectomy, the posterior semicircular canal is identified, and Donaldson's line is determined. This is a line through the horizontal semicircular canal, crossing the posterior semicircular canal. The endolymphatic sac is usually found at this site under the posterior semicircular canal. The bone of the endolymphatic sac and the dura are thinned until the sac is skeletonized, after which the endolymphatic duct is identified. The duct is then blocked with a titanium clip. Using a computerized tomography (CT) scan, the position is confirmed. Follow-up visits take place 1 week, 6 weeks and 1 year after surgery. To this day, only one prospective trial assessing this method has been conducted, comparing this new method to endolymphatic sac decompression. Results of the duct blockage are promising, with 96.5% of the patients free of vertigo after 2 years. However, further research is required.

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.

Radiological presence of vascular loops in the cerebellopontine angle region in patients with unilateral Ménière's disease.

OBJECTIVE: The relationship between vascular compression of the vestibulocochlear nerve and audio-vestibular symptoms remains controversial. We aimed to examine the radiological features of vascular loops signs in cerebellopontine angle (CPA) and internal auditory canal (IAC) in patients with unilateral Ménière's disease (MD). METHODS: One hundred and thirty-seven patients with unilateral definite MD and 69 control subjects (138 ears) were enrolled. All subjects received magnetic resonance imaging of CPA-IAC. The configuration of vascular loops in CPA-IAC, based on the Kazawa classification system, from MD-affected, non-affected and control ears were compared. The associations between imaging findings and Ménière's stage, electrocochleogram (EcochG) and caloric test were analyzed. RESULTS: (1) Among the MD-affected ears, 6 cases (4.4%) were classified as Kazawa type IA, 27 cases (19.7%) as IB, 60 cases (43.8%) as IIA, and 44 cases (32.1%) as IIB. No significant interaural difference in the distribution of Kazawa's types was found ([Formula: see text] = 4.737, p = 0.578) in unilateral MD patients. (2) The distribution of Kazawa's types were not significantly different between the MD-affected ears and the control subjects ([Formula: see text] = 2.876, p = 0.411). (3) No relationship was found between Kazawa staging of the MD-affected ear and Ménière's stage (H = 2.679, p = 0.444), EcochG ([Formula: see text] = 0.827, p = 0.867) and caloric test ([Formula: see text] = 4.116, p = 0.248). CONCLUSIONS: In patients with unilateral MD, the configuration of vascular loops in CPA-IAC region, measured by Kazawa criteria, did not correlate with the laterality, clinical stage, the results of EcochG and caloric test, suggesting that vascular loops may be natural anatomical variations for patients with MD.

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.

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.

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.

Signal Alteration of the Inner Ear on High-Resolution Three-Dimensional Constructive Interference in Steady State Sequence in Patients with Ménière's Disease and Labyrinthitis.

INTRODUCTION: The aim of this study is to evaluate signal alteration in the inner ear using three-dimensional (3D)-constructive interference in steady state (CISS) sequence in patients with Ménière's disease and labyrinthitis and its correlation with clinical and audiological parameters. METHODS: The medical records of the department of otorhinolaryngology were searched for patients with Ménière's disease or labyrinthitis who underwent MRI with 3D-CISS sequence. Blinded analysis of these patients and of MRI from control subjects without middle or inner ear symptoms was performed to detect any signal asymmetry of the inner ear structures. The results were correlated with clinical symptoms and results of audiological and vestibular tests. RESULTS: Fifty-eight patients with definite Ménière's disease and 5 patients with labyrinthitis as well as 41 control exams were included. A separate analysis was performed for patients with probable Ménière's disease (n = 68). A total of 172 3D-CISS sequences were analyzed by 2 blinded independent neuroradiologists. A CISS-hypointense signal of the inner ear structures was found in 3 patients with definite Ménière's disease (5.2%), in 4 patients with probable Ménière's disease (5.9%), and 2 patients with labyrinthitis (40%). No CISS hypointensity was found in the control group. Although no significant difference in symptoms or audiological test results was found between patients with and without this signal change, the side of hypointensity was frequently correlated with the symptomatic side and with hearing impairment. DISCUSSION/CONCLUSION: CISS hypointensity of the inner ear structures was evident in patients with clinical conditions other than vestibular schwannoma - more frequently in labyrinthitis than in Ménière's disease. This signal alteration was frequently encountered on the same symptomatic side as that of the pathological audiology tests, but it is not a predictor for hearing or vestibular impairment.

Inner ear MRI enhancement based on three dimensional-real IR sequence in patients with Meniere's disease after intravenous gadolinium injection: Comparison of different doses used and exploration of an appropriate dose.

OBJECTIVES: Three-dimensional inversion-recovery sequence with real reconstruction (3D-real IR) magnetic resonance imaging (MRI) can detect endolymphatic hydrops of the inner ear. We aimed to explore a appropriate dose for intravenous gadolinium injection. DESIGN: Observational prospective study. SETTING: Tertiary referral centre. PARTICIPANTS: We collected 90 unilateral definite Meniere's disease patients. MAIN OUTCOME MEASURES: All enrolled patients were divided into three groups randomly (patients in group A, B and C received gadolinium injection in 1/1.5/2 times doses respectively). After 4 h, inner ear MRI scans were applied. RESULTS: The signal intensities of B-affected ears and C-affected ears were significantly higher than A-affected ears (p < .05); however, no difference was found between B-affected ears and C-affected ears (p = .267). The same conditions also appeared in the three unaffected-ear groups. Moreover, the signal intensities of affected-ear in group A, B and C were significantly higher than that of the corresponding unaffected-ear groups (p < .05). Besides, the subjective visual evaluation scores of group B and C were significantly better than that of group A (p < .05). CONCLUSIONS: Intravenous injection of gadolinium in a single dose may be unbefitting for the inner ear imaging based on 3D-real IR MRI, both the applications of gadolinium in 1.5 times and double doses can have a good perilymphatic enhancement effect of inner ear. In order to minimise the use of dose for avoiding or mitigating the adverse reactions and renal damage, 1.5 times dose may be preferred in clinical practice.

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.

High-quality imaging of endolymphatic hydrops acquired in 7 minutes using sensitive hT2W-3D-FLAIR reconstructed with magnitude and zero-filled interpolation.

BACKGROUND: It is still challenging to detect endolymphatic hydrops (EH) in patients with Meniere's disease (MD) using MRI. The aim of the present study was to optimize a sensitive technique generating strong contrast enhancement from minimum gadolinium-diethylenetriamine pentaacetic acid (Gd-DTPA) while reliably detecting EH in the inner ear, including the apex. MATERIALS AND METHODS: All imaging was performed using a 3.0 T MR system 24 h after intratympanic injection of low-dose Gd-DTPA. Heavily T2-weighted 3-dimensional fluid-attenuated inversion recovery reconstructed with magnitude and zero-filled interpolation (hT2W-FLAIR-ZFI) was optimized and validated in phantom studies and compared with medium inversion time inversion recovery imaging with magnitude reconstruction (MIIRMR). The following parameters were used in hT2W-FLAIR-ZFI: repetition time 14,000 ms, echo time 663 ms, inversion time 2900 ms, flip angle 120°, echo train length 271, and field of view 166 × 196 mm2. RESULTS: MRI obtained using hT2W-FLAIR-MZFI yielded high-quality images with sharper and smoother borders between the endolymph and perilymph and a higher signal intensity ratio and more homogenous perilymph enhancement than those generated with MIIRMR (p < 0.01). There were predominantly grade II EHs in the cochleae and grade III EHs in the vestibule in definite MD. EH was detected in the apex of 11/16 ipsilateral ears, 3/16 contralateral ears in unilateral definite MD and 3/6 ears in bilateral MD. CONCLUSIONS: The novel hT2W-FLAIR-MZFI technique is sensitive and demonstrates strong and homogenous enhancement by minimum Gd-DTPA in the inner ear, including the apex, and yields high-quality images with sharp borders between the endolymph and perilymph.