The Correlation Between Endolymphatic Hydrops and Clinical Features of Meniere Disease

Correlation of endolymphatic hydrops and perilymphatic enhancement with the clinical features of Ménière's disease

OBJECTIVES

To use three-dimensional real inversion recovery (3D-real IR) MRI to investigate correlations between endolymphatic hydrops (EH) grades or the degree of perilymphatic enhancement (PE) and clinical features of Ménière's disease (MD), as previous findings have been inconsistent.

METHODS

A total of 273 consecutive patients with definite unilateral MD were retrospectively enrolled from September 2020 to October 2021. All patients underwent 3D-real IR and 3D-T2WI 6 h after intravenous gadolinium injection. MD-related symptom duration and vertigo frequency were recorded. EH grades were evaluated, the signal intensity ratio (SIR) was measured, and correlations between clinical features and EH, PE were assessed respectively.

RESULTS

The study included 123 males and 150 females, with a mean age of 53.0 years. A longer duration of vertigo was associated with higher cochlear EH grades, whereas the opposite was true for the duration of aural fullness. A longer time since vertigo onset was associated with higher vestibular EH grades; the opposite was true for the duration of individual vertigo attacks. The multiple regression analysis revealed that age, tinnitus duration, and vestibular EH were risk factors for SIR. Furthermore, the low-frequency hearing threshold (HT) was a risk factor for cochlear and vestibular EH, and the SIR.

CONCLUSION

The EH grade and SIR (an indicator for the quantitative evaluation of PE) were correlated with clinical features and HT of MD; thus, imaging can be a valuable tool in planning individualised treatment.

CLINICAL RELEVANCE STATEMENT

This study revealed that the grade of endolymphatic hydrops and degree of perilymphatic enhancement positively correlates with the length of time since onset of clinical symptoms and hearing thresholds in patients with Ménière's disease, facilitating the tailored treatment.

KEY POINTS

• Relationships between 3-dimensional real inversion recovery features and clinical symptoms in Ménière's disease are unknown. • Symptom duration and hearing thresholds correlated with endolymphatic hydrops grades and degree of perilymphatic enhancement. • MRI features correlate with MD severity; thus, imaging is valuable for planning tailored treatment.

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.

Hearing, balance, and imaging assessment in adolescent Menière's disease: A retrospective analysis

Objective

To retrospectively analyze clinical features in adolescent Menière's disease (MD).

Methods

The medical records of adolescents with MD (11-17 years old) from May 2014 to March 2023 in Shandong Provincial ENT Hospital were retrospectively analyzed, including clinical features, a battery of auditory and vestibular function tests, sensory organization test, and imaging assessments. Patients with recurrent vertigo of childhood (RVC) were as controls.

Results

Compared with RVC, adolescent MD showed higher pure tone average threshold (p < .001), lower speech discrimination score (p = .014), and lower otoacoustic emission pass rates (p = .005). Adolescents with MD exhibited significant reduction in equilibrium score (Conditions 1, 5, and 6; p1 = .035; p5 = .033; p6 = .003), composite sensory score (p = .014), and vestibular sensory score (p = .029). Adolescents with bilateral MD exhibited worse performance in equilibrium score and strategy score compared to adolescents with unilateral MD. For the affected ear, the more severe endolymphatic hydrops detected by gadolinium-enhanced magnetic resonance imaging, the higher the auditory brainstem response threshold (r = .850, p = .007), and the lower the otoacoustic emission pass rate (r = -.976, p < .001).

Conclusion

Adolescent MD has similar vestibular information inputs with that of RVC, but the ability for the nerve center to use these clues to maintain balance is worse in adolescents with MD. There were potential differences in vestibular weights in adolescents with unilateral and bilateral MD, also potential effects on vision and proprioception.

Level of Evidence

Level 4.

The correlation of hearing prognosis and caloric test results in Meniere's disease: a follow up study

BACKGROUND

Hearing loss is important in the diagnosis and treatment of Meniere's disease (MD). However, little is known about the factors associated with hearing changes in MD.

AIMS/OBJECTIVES

This study aimed to investigate the correlation between hearing prognosis and caloric test (CT) results in MD.

MATERIAL AND METHODS

Ninety consecutive patients diagnosed with unilateral definite MD underwent pure tone audiometry (PTA) and CT at initial visits, and were re-tested PTA at the 6-month follow-up.

RESULTS

Fifty-three of ninety MD patients (58.89%) had abnormal CT results. The change of PTA (cPTA = initial PTA-last PTA) was negatively correlated with canal paresis (CP) values (overall association p = 0.032 and non-linear association p = 0.413). Multivariate linear model showed that as the CP value changed from 0 to 1, the cPTA decreased by -13.31 dB (95% CI: -24.03, -2.6) (p = 0.016). Stratified analysis found that the association was present in MD patients of Stage 1 and 2 (p < 0.05) but not in patients of Stage 3 and 4 (p > 0.05).

CONCLUSIONS AND SIGNIFICANCE

Elevated CP values may be linked to worse hearing outcomes in MD, especially in Stage 1 and 2 patients. Conducting a caloric test at the initial consultation may aid in assessing hearing regression in MD.

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.

15-year follow-up for steroid-responsive, fluctuating hearing loss in the ear with endolymphatic hydrops confirmed by magnetic resonance imaging

Autoimmune mechanisms may play crucial roles in the etiology of endolymphatic hydrops (ELH), which was previously regarded as a postmortem finding in the temporal bone. Recently, ELH has been visualized using 3-T MR imaging in living patients. A 47-year-old woman with deafness in the left ear since adolescence developed right-sided steroid-responsive sensorineural hearing loss in the low frequencies. During over 15 years of follow-up at our otolaryngology clinic, acute deteriorations of hearing in the only hearing ear repeatedly recovered with administration of intravenous and oral steroids. Hearing in the only hearing ear at 62 years old was preserved and comparable to that at 47 years old. At 61 years old, cochlear ELH was documented bilaterally on MR imaging, appearing more severe in the deafened ear than in the hearing ear. This case provides new evidence of the potential steroid-responsiveness of hearing loss due to contralateral-type delayed ELH distinctly visualized on MR imaging.

Evaluation of the relationship between endolymphatic hydrops and hearing loss in Meniere's disease based on three-dimensional real inversion recovery sequence

OBJECTIVES

The degree of endolymphatic hydrops in Meniere's disease may be related to hearing loss. However, the results of prior studies have been inconsistent. We aimed to investigate the relationship between endolymphatic hydrops and hearing loss characteristics in Meniere's disease.

METHODS

This study included 54 patients (62 ears) with Meniere's disease. Patients underwent three-dimensional real inversion recovery sequences for magnetic resonance imaging and pure-tone audiometry. Endolymphatic hydrops were assessed according to Gurkov's criteria (2011). Correlations between different degrees of endolymphatic hydrops and pure-tone audiometry, as well as staging, were analysed.

RESULTS

Pure tone audiometry and staging were higher for vestibular endolymphatic hydrops complicated by cochlear ones than isolated cochlear or vestibular hydrops (both p < 0.05). There was no significant correlation between vestibular endolymphatic hydrops and pure-tonal audiometry or staging (all p > 0.05). The degree of hydrops in the middle turn was correlated with the mid-frequency hearing threshold (p < 0.05). The degree of cochlear hydrops was correlated with the audiometry, low-frequency hearing thresholds, mid-frequency hearing thresholds and staging (p < 0.01).

CONCLUSION

The types and sites of endolymphatic hydrops based on a 3D-real inversion recovery sequence can be used to indicate the degree of hearing loss in patients with Meniere's disease.

LEVEL OF EVIDENCE

Level III.

Functional and Molecular Markers for Hearing Loss and Vertigo Attacks in Meniere's Disease

Meniere's disease (MD) is one of the most complicated diseases in the otologic clinic. The complexity of MD is partially due to the multifactorial etiological mechanisms and the heterogenous symptoms, including episodic vertigo, hearing loss, aural fullness and tinnitus. As a result, the diagnosis of MD and differentiating MD from other diseases with similar symptoms, such as vestibular migraine (VM), is challenging. In addition, it is difficult to predict the progression of hearing loss and the frequency of vertigo attacks. Detailed studies have revealed that functional markers, such as pure tone audiometry (PTA), electrocochleography (ECochG), vestibular evoked myogenic potential (VEMP), caloric test, video head impulse test (vHIT) and magnetic resonance imaging (MRI) could help to evaluate MD with different hearing levels and frequency of vertigo attacks. Investigations of molecular markers such as autoimmunity, inflammation, protein signatures, vasopressin and circadian clock genes in MD are still underway. This review will summarize these functional and molecular markers, address how these markers are associated with hearing loss and vertigo attacks in MD, and analyze the results of the markers between MD and VM.

Microstructural changes of the vestibulocochlear nerve in patients with Ménière's disease using diffusion tensor imaging

Objective

To evaluate the microstructural changes of the vestibulocochlear nerve in patients with Ménière's disease.

Methods

A total of 26 subjects, 13 patients with MD and 13 healthy controls, underwent diffusion tensor imaging (DTI) on a 3T scanner. The independent sample t-test was used to compare the differences in fractional anisotropy (FA) and apparent diffusion coefficient (ADC) between the two groups. A Pearson correlation was used between DTI and the dizziness handicap inventory (DHI) scores.

Results

There was a significant decrease in FA and an increase in ADC of the vestibulocochlear nerve in MD patients compared with healthy controls (P = 0.04, P = 0.001). FA had negative correlations with the DHI score (r = −0.62, P = 0.02) and DHI-functional score (r = −0.64, P = 0.02).

Conclusion

These results are the first evidence of possible changes in the microstructure of the vestibulocochlear nerves in patients with MD. DTI is a potential technique for evaluating the vestibulocochlear nerve in patients with MD.

Magnetic resonance imaging of endolymphatic hydrops in Ménière's disease: A comparison of the diagnostic value of multiple scoring methods

Objectives

To compare three methods of scoring endolymphatic hydrops in patients with Ménière's disease in order to assess the correlation between endolymphatic hydrops and auditory characteristics.

Methods

A retrospective study of 97 patients with unilateral definite Ménière's disease (DMD) who underwent contrast-enhanced three-dimensional fluid attenuated inversion recovery (3D FLAIR) MRI. Each patient was scored by the Inner Ear Structural Assignment Method (IESAM), the Saccule to utricle area ratio (SURI), and the Four Stage Vestibular Hydrops Grading (FSVH), according to their corresponding axial images. Cohen's Kappa and intra-class correlation coefficient were used for consistency testing, combined with binary logistic regression analysis, to compare the sensitivity and specificity of the three methods. The degree of hydrops in different stages of MD was compared. The correlation between endolymphatic hydrops in the inner ear sub-units and hearing thresholds was further analyzed.

Results

The intra- and inter-reader reliability for the scoring of endolymphatic hydrops were excellent. The IESAM had a high diagnostic value for identifying definite Ménière's disease (sensitivity: 86.6%, specificity: 97.9%). The hearing thresholds were correlated with the degree of endolymphatic hydrops. Stages 3 and 4 were more significant for the severity of hydrops than stage 1. Within the subgroups of the Ménière's disease patients, compared with the non-hydrops group and the pure vestibular hydrops (V group), the cochlear combined vestibular hydrops group (CV group) had significantly higher auditory thresholds. The amplitude ratio of electrocochleogram was significantly higher in the affected ear than in the healthy ear.

Conclusion

The IESAM is a more sensitive and specific diagnostic scoring method for the diagnosis of DMD. Diagnostic imaging may improve the detection of inner ear hydrops which is correlated with severity of hearing loss. A comprehensive evaluation of the inner ear sub-unit structures maybe necessary.

Correlation of clinical parameters with endolymphatic hydrops on MRI in Meniere's disease

A clinical diagnosis of Ménière's disease (MD) is made based on medical history and audiometry findings. The 1995 American Academy of Otolaryngology-Head and Neck Surgery (AAO-HNS) guidelines requires histopathological confirmation of endolymphatic hydrops (EH) for a diagnosis of “certain” MD. Symptoms such as dizziness and ear fullness are important diagnostic features; however, the descriptions provided by patients are frequently vague and non-specific. A recently developed magnetic resonance imaging (MRI) protocol to document EH is, therefore, useful for the evaluation of inner ear status in patients with MD. In this study, patients with MD were assessed using MRI and the HYDROPS (HYbriD of Reversed image Of Positive endolymph signal and native image of positive perilymph Signal) protocol to investigate the effectiveness of MRI for visualization of the endolymphatic space in the diagnosis of MD by correlating clinical laboratory parameters with the grade of EH. Of the 123 patients with MD recruited in this study, 80 had definite MD, 11 had probable MD, and 32 had possible MD based on the 1995 AAO-HNS guidelines. The EH grade based on HYDROPS MRI was determined independently by two otorhinolaryngologists and compared with several clinical parameters, including the diagnostic scale of MD (1995 AAO-HNS guidelines), pure tone average (PTA), low tone average (LTA), canal paresis (CP) on the caloric test, and disease duration. Cochlear hydrops and vestibular hydrops were detected in 58 and 80% of 80 definite MD ears, in 33 and 58% of 12 probable MD ears, and in 5 and 27% of 37 possible MD ears, respectively. The proportion of higher hydrops grades increased significantly with grade according to the MD diagnostic scale (p < 0.0001). Both PTA and LTA were significantly higher in patients with hydrops grade 2 than hydrops grade 0 in both the cochlea and the vestibule. CP was significantly higher in patients with grade 2 than grade 0 vestibular hydrops. Disease duration was not associated with hydrops grade. Radiological evaluation of MD using the HYDROPS protocol is useful for evaluation of the extent and severity of EH in the diagnosis of MD based on its pathophysiological mechanism.

Development and Characteristics of Hearing Loss With the Progression of Endolymphatic Hydrops

OBJECTIVES

This study aims to explore how patients' hearing loss developed with the progression of endolymphatic hydrops and the characteristics of hearing loss at different stages.

MATERIALS AND METHODS

We collected 73 patients with definite or possible unilateral Meniere's disease or sudden hearing loss who underwent magnetic resonance imaging after intravenous contrast agent injection. There were 25 cases of isolated cochlear hydrops, 24 cases of isolated vestibular hydrops, and 24 cases of cochlear and vestibular hydrops. Primary outcome analyses included their evaluation of endolymphatic hydrops and hearing thresholds at low and high frequencies.

RESULTS

The overall hearing threshold of patients with vestibular and cochlear hydrops was significantly higher than that of patients with isolated cochlear hydrops and patients with isolated vestibular hydrops. There was a significant correlation between low-frequency hearing loss and cochlear hydrops, and the low-frequency hearing threshold was proportional to the grade of cochlear hydrops. At low frequency, the hearing threshold of patients with isolated vestibular hydrops was lower than that of patients with isolated cochlear hydrops and patients with both cochlear and vestibular hydrops. The audiogram configurations of patients with isolated cochlear hydrops consist largely of flat type and up-sloping type. The audiogram configurations of patients with isolated vestibular hydrops and patients with both cochlear and vestibular hydrops are mainly flat type and down-sloping type.

CONCLUSIONS

Patients present with low-frequency hearing loss in the early stage of endolymphatic hydrops. When the hydrops involves the whole cochlea and vestibule, the patients' hearing is impaired at both low and high frequencies.

The Role of Wideband Tympanometry in the Diagnosis of Meniere's Disease

Meniere's disease (MD) is a clinical syndrome characterized by spontaneous recurrent vertigo, usually accompanied by hearing loss, tinnitus, and aural fullness. The cause of MD remains unclear and is generally considered to be associated with endolymphatic hydrops. Studies showed that patients with MD could have eustachian tube dysfunction (ETD). ETD can disrupt the pressure balance between the middle and inner ear and impair the inner ear's function. In recent years, several studies have attempted to identify MD by using wideband tympanometry (WBT). However, there are limited studies in this area. There is no consensus on how to use WBT to diagnose Meniere's disease. Therefore, we endeavored to conduct a narrative review in this aspect based on the latest research findings. Reduction in resonance frequency and absorbance are characteristic of MD and can identify Meniere's disease. The use of an increase in the integrated area of absorbance as an indicator for identifying MD is controversial. WBT seems to be ineffective as a diagnostic tool during the acute episodes of Meniere's disease. Patients with MD may benefit from WBT. WBT has excellent potential for future use in Meniere's disease. However, further large sample sizes, multicenter studies are needed.

Three-Dimensional Volumetric Measurement of Endolymphatic Hydrops in Meniere's Disease

Objective: We used volumetric three-dimensional (3D) analysis to quantitatively evaluate the extent of endolymphatic hydrops (EH) in the entire inner ear. We tested for correlations between the planimetric and volumetric measurements, to identify their advantages and disadvantages. Methods: HYDROPS2-Mi2 EH images were acquired for 32 ears (16 patients): 16 ipsilateral ears of MD patients (MD-ears) and 16 contralateral ears. Three-T MR unit with a 32-channel phased-array coil/the contrast agent to fill the perilymphatic space and the HYDROPS2-Mi2 sequence. We calculated the EH% [(endolymph)/(endolymph+perilymph)] ratio and analyzed the entire inner ear in terms of the volumetric EH% value, but only single cochlear and vestibular slices were subjected to planimetric EH% evaluation. The EH% values were compared between MD ears and non-MD ears, to evaluate the diagnostic accuracy of the two methods. Results: The volumetric EH% was significantly higher for MD vestibules (50.76 ± 13.78%) than non-MD vestibules (39.50 ± 8.99%). The planimetric EH% was also significantly higher for MD vestibules (61.98 ± 20.65%) than non-MD vestibules (37.22 ± 12.95%). The vestibular and cochlear volumetric EH% values correlated significantly with the planimetric EH% values of the MD ear. Conclusion: Volumetric and planimetric EH measurements facilitate diagnosis of MD ears compared to non-MD ears. Both methods seem to be reliable and consistent; the measurements were significantly correlated in this study. However, the planimetric EH% overestimates the extent of vestibular hydrops by 26.26%. Also, planimetric data may not correlate with volumetric data for non-MD cochleae with normal EH% values.

Advanced Imaging of the Vestibular Endolymphatic Space in Ménière's Disease

The diagnosis of "definite" Méniére's disease (MD) relies upon its clinical manifestations. MD has been related with Endolymphatic Hydrops (EH), an enlargement of the endolymphatic spaces (ES) (cochlear duct, posterior labyrinth, or both). Recent advances in Magnetic Resonance (MR) imaging justify its increasing role in the diagnostic workup: EH can be consistently recognized in living human subjects by means of 3-dimensional Fluid-Attenuated Inversion-Recovery sequences (3D-FLAIR) acquired 4 h post-injection of intra-venous (i.v.) Gadolinium-based contrast medium, or 24 h after an intratympanic (i.t.) injection. Different criteria to assess EH include: the comparison of the area of the vestibular ES with the whole vestibule on an axial section; the saccule-to-utricle ratio ("SURI"); and the bulging of the vestibular organs toward the inferior 1/3 of the vestibule, in contact with the stapedial platina ("VESCO"). An absolute link between MD and EH has been questioned, since not all patients with hydrops manifest MD symptoms. In this literature review, we report the technical refinements of the imaging methods proposed with either i.t. or i.v. delivery routes, and we browse the outcomes of MR imaging of the ES in both MD and non-MD patients. Finally, we summarize the following imaging findings observed by different researchers: blood-labyrinthine-barrier (BLB) breakdown, the extent and grading of EH, its correlation with clinical symptoms, otoneurological tests, and stage and progression of the disease.

Association between Statin Use and Meniere's Disease: Results from a National Health Screening Cohort

The protective effects of statins against inner ear diseases have been suggested. This study investigated the relationship between previous statin use and the occurrence of Meniere’s disease (MD). Participants ≥40 years old in the Korean National Health Insurance Service-Health Screening Cohort 2002–2015 were enrolled. A total of 7734 MD participants were matched with 38,670 comparison participants. The dates of statin prescriptions for the 2 years before the onset of MD were examined. A conditional logistic regression analysis was performed to estimate the odds ratios (ORs) of statin use for MD. Regarding the different types of statins, lipophilic statins, but not hydrophilic statins, were associated with lower odds of MD in the <65 year-old group (adjusted OR = 0.81, 95% CI = 0.68–0.97, p = 0.023). Prior statin use did not show association with MD in the adult population. Regarding the different types of statins, lipophilic statin use was related to a lower rate of MD in a middle-aged population.

New Frontiers in Managing the Dizzy Patient

Despite progress in vestibular research in the last 20 years, much remains poorly understood about vestibular pathophysiology and its management. A shared language is a critical first step in understanding vestibular disorders and is under development. Telehealth will continue for patients with dizziness, and ambulatory monitoring of nystagmus will become a diagnostic tool. In the next 2 decades, it is anticipated that vestibular perceptual threshold testing will become common in tertiary centers, imaging with improved spatial resolution will yield better understanding of vestibular pathophysiology, and that vestibular implants will become a part of clinical practice.

Enhancement of subarachnoid space during magnetic resonance imaging of endolymphatic hydrops: a case report

Enhancement of the subarachnoid space after intravenous administration of gadolinium contrast agent is not common. Enhancement usually occurs in pathological conditions that increase the permeability of the blood–cerebrospinal fluid barrier, most notably in meningitis. We herein describe possible subarachnoid enhancement in patients with no apparent effect on the meninges. These patients had clinical signs of Meniere’s disease and underwent specific magnetic resonance imaging of the inner ear to possibly visualize endolymphatic hydrops. The endolymphatic space can be noninvasively imaged by intravenous administration of contrast agent, usually at a double dose, 4 hours before the scanning process. During this time, the contrast agent penetrates not only the perilymph but also the subarachnoid space, where the highest concentration occurs after 4 hours according to some studies.

MR Imaging of Endolymphatic Hydrops in Five Minutes

In this study, we present images acquired by a fast-imaging method for the evaluation of endolymphatic hydrops after intravenous administration of a single dose of gadolinium-based contrast agent. We utilized the hybrid of reversed image of MR cisternography and a positive perilymph signal by heavily T2- weighted 3D-fluid attenuated inversion recovery-multiplied by T2 (HYDROPS2-Mi2) method combined with deep learning reconstruction denoising. The scan time for the fast protocol was approximately 5 mins, which is far shorter than previously reported scan times. The fast acquisition provides similar image quality and less motion artifacts compared to the longer method.

Intravenous Delayed Gadolinium-Enhanced MR Imaging of the Endolymphatic Space: A Methodological Comparative Study

In-vivo non-invasive verification of endolymphatic hydrops (ELH) by means of intravenous delayed gadolinium (Gd) enhanced magnetic resonance imaging of the inner ear (iMRI) is rapidly developing into a standard clinical tool to investigate peripheral vestibulo-cochlear syndromes. In this context, methodological comparative studies providing standardization and comparability between labs seem even more important, but so far very few are available. One hundred eight participants [75 patients with Meniere's disease (MD; 55.2 ± 14.9 years) and 33 vestibular healthy controls (HC; 46.4 ± 15.6 years)] were examined. The aim was to understand (i) how variations in acquisition protocols influence endolymphatic space (ELS) MR-signals; (ii) how ELS quantification methods correlate to each other or clinical data; and finally, (iii) how ELS extent influences MR-signals. Diagnostics included neuro-otological assessment, video-oculography during caloric stimulation, head-impulse test, audiometry, and iMRI. Data analysis provided semi-quantitative (SQ) visual grading and automatic algorithmic quantitative segmentation of ELS area [2D, mm²] and volume [3D, mm³] using deep learning-based segmentation and volumetric local thresholding. Within the range of 0.1-0.2 mmol/kg Gd dosage and a 4 h ± 30 min time delay, SQ grading and 2D- or 3D-quantifications were independent of signal intensity (SI) and signal-to-noise ratio (SNR; FWE corrected, p < 0.05). The ELS quantification methods used were highly reproducible across raters or thresholds and correlated strongly (0.3-0.8). However, 3D-quantifications showed the least variability. Asymmetry indices and normalized ELH proved the most useful for predicting quantitative clinical data. ELH size influenced SI (cochlear basal turn p < 0.001), but not SNR. SI could not predict the presence of ELH. In conclusion, (1) Gd dosage of 0.1-0.2 mmol/kg after 4 h ± 30 min time delay suffices for ELS quantification. (2) A consensus is needed on a clinical SQ grading classification including a standardized level of evaluation reconstructed to anatomical fixpoints. (3) 3D-quantification methods of the ELS are best suited for correlations with clinical variables and should include both ears and ELS values reported relative or normalized to size. (4) The presence of ELH increases signal intensity in the basal cochlear turn weakly, but cannot predict the presence of ELH.

Differential Diagnosis of Endolymphatic Hydrops Between "Probable" and "Definite" Ménière's Disease via Magnetic Resonance Imaging

OBJECTIVES

To investigate the grade of endolymphatic hydrops in patients with "probable" and "definite" Ménière's disease via magnetic resonance imaging (MRI) and to determine whether MRI could assist clinicians in differential diagnosis between probable and definite Ménière's disease.

STUDY DESIGN

Prospective study.

SETTING

Three-dimensional FLAIR MRI (fluid-attenuated inversion recovery) to examine endolymphatic hydrops in Ménière's disease.

METHODS

A total of 51 patients diagnosed with probable (n = 20) or definite (n = 31) unilateral Ménière's disease were enrolled. Three-dimensional FLAIR MRI was performed to evaluate the grade of endolymphatic hydrops. The differences in endolymphatic hydrops between the probable and definite groups were analyzed.

RESULTS

The grade of endolymphatic hydrops was more severe in the definite group than in the probable group (P < .05).

CONCLUSION

MRI revealed a higher grade of endolymphatic hydrops in patients with definite Ménière's disease than in patients with probable Ménière's disease. As a result, it may be clinically useful and an effective tool in the differentiation between definite and probable Ménière's disease.

Comparative Study Between the Auditory and Vestibular Functions in Ménière's Disease

OBJECTIVES

To evaluate the relationship between the loss of the cochleovestibular functions in Ménière's disease (MD).

METHODS

Forty-three patients with definite MD underwent pure-tone audiometry (PTA) and caloric test. Canal paresis (CP%), dPTA (interaural difference), and average PTA results were contrasted. IBM SPSS V24 was used for statistical analysis.

RESULTS

According to PTA, most patients were in stage C, and caloric weakness was found in 29 patients. Linear (R ² = 0.06) and nonlinear correlation tests (rho = 0.245, P = .113) between canal paresis (CP%) and dPTA showed no correlation, as well as between CP% and PTA analysis (R ² = 0.007, rho = 0.11, P = .481). As per the categorial analysis, no correlation was detected between the groups either (κ = 0.174, 95% CI: 0.0883 - 0.431). Based on the results of the analysis, it was concluded that a more advanced stage determined by audiometry does not indicate increasing values in the CP% parameter.

CONCLUSIONS

Audiometric changes do not directly correspond with the vestibular ones; therefore, no specific correlation exists between them. Thus, for therapy planning and diagnosis, both tests are necessary.

The Correlation Between Endolymphatic Hydrops and blood-labyrinth barrier Permeability of Meniere Disease

OBJECTIVES

This study was designed to assess the correlation between the grades of endolymphatic hydrops and the blood-labyrinth barrier permeability in the affected ear in Meniere's disease, following the administration of intravenous gadolinium contrast.

STUDY DESIGN

Prospective study.

METHODS

The quantitative values of endolymphatic hydrops were determined after intravenous injection of a double-dose of gadobutrol in 39 patients with unilateral definite Meniere's disease. Additionally, the signal intensity ratio of bilateral cochlear basal turns was evaluated and analyzed; The correlation between the grades of the endolymphatic hydrops and the signal intensity ratio of the cochlear basal turns in the affected ear was examined.

RESULTS

The grades of the endolymphatic hydrops can be quantitatively evaluated using magnetic resonance imaging (MRI). The signal intensity ratio of the cochlear basal turns in the affected ear was significantly higher than in the unaffected ear (P = .001); there was a positive correlation between the signal intensity ratio of the cochlear basal turn and the grades of cochlear (r = 0.634, P = 0.000) and vestibular(r = 0.559, P = .000) hydrops in the affected ear.

CONCLUSIONS

The increased permeability of the blood-labyrinth barrier may play a role in the process of endolymphatic hydrops in Meniere's disease.

State of the Art Imaging in Menière’s Disease. Tips and Tricks for Protocol and Interpretation

Purpose of Review

Menière’s disease (MD) is a burdensome and not well understood inner ear disorder that has received increasing attention of scientists over the past decade. Until 2007, a certain diagnosis of endolymphatic hydrops (EH) required post-mortem histology. Today, dedicated high-resolution magnetic resonance imaging (MRI) protocols enable detection of disease-related changes in the membranous labyrinth in vivo. In this review, we summarize the current status of MR imaging for MD.

Recent Findings

The mainstays of hydrops imaging are inversion recovery sequences using delayed acquisition after intravenous or intratympanic contrast administration. Based on these techniques, several methods have been developed to detect and classify EH. In addition, novel imaging features of MD, such as blood-labyrinth barrier impairment, have recently been observed.

Summary

Delayed contrast enhanced MRI has emerged as a reliable technique to demonstrate EH in vivo, with promising application in the diagnosis and follow-up of MD patients. Therefore, familiarity with current techniques and diagnostic imaging criteria is increasingly important.

MR Imaging of Endolymphatic Hydrops: Utility of iHYDROPS-Mi2 Combined with Deep Learning Reconstruction Denoising

Purpose:

MRI of endolymphatic hydrops (EH) 4 h after intravenous administration of a single dose of gadolinium-based contrast agent is used for clinical examination in some institutions; however, further improvement in image quality would be valuable for wider clinical utility. Denoising using deep learning reconstruction (Advanced Intelligent Clear-IQ Engine [AiCE]) has been reported for CT and MR. The purpose of this study was to compare the contrast-to-noise ratio of endolymph to perilymph (CNR_EP) between the improved hybrid of reversed image of the positive endolymph signal and the native image of the perilymph signal multiplied with the heavily T₂-weighted MR cisternography (iHYDROPS-Mi2) images, which used AiCE for the three source images (i.e. positive endolymph image [PEI], positive perilymph image [PPI], MR cisternography [MRC]) to those that did not use AiCE. We also examined if there was a difference between iHYDROPS-Mi2 images with and without AiCE for degree of visual grading of EH and in endolymphatic area [EL] ratios.

Methods:

Nine patients with suspicion of EH were imaged on a 3T MR scanner. iHYDROPS images were generated by subtraction of PEI images from PPI images. iHYDROPS-Mi2 images were then generated by multiplying MRC with iHYDROPS images. The CNR_EP and EL ratio were measured on the iHYDROPS-Mi2 images. Degree of radiologist visual grading for EH was evaluated.

Results:

Mean CNR_EP ± standard deviation was 1681.8 ± 845.2 without AiCE and 7738.6 ± 5149.2 with AiCE (P = 0.00002). There was no significant difference in EL ratio for images with and without AiCE. Radiologist grading for EH agreed completely between the 2 image types in both the cochlea and vestibule.

Conclusion:

The CNR_EP of iHYDROPS-Mi2 images with AiCE had more than a fourfold increase compared with that without AiCE. Use of AiCE did not adversely affect radiologist grading of EH.

VOLT: a novel open-source pipeline for automatic segmentation of endolymphatic space in inner ear MRI

Background

Objective and volumetric quantification is a necessary step in the assessment and comparison of endolymphatic hydrops (ELH) results. Here, we introduce a novel tool for automatic volumetric segmentation of the endolymphatic space (ELS) for ELH detection in delayed intravenous gadolinium-enhanced magnetic resonance imaging of inner ear (iMRI) data.

Methods

The core component is a novel algorithm based on Volumetric Local Thresholding (VOLT). The study included three different data sets: a real-world data set (D1) to develop the novel ELH detection algorithm and two validating data sets, one artificial (D2) and one entirely unseen prospective real-world data set (D3). D1 included 210 inner ears of 105 patients (50 male; mean age 50.4 ± 17.1 years), and D3 included 20 inner ears of 10 patients (5 male; mean age 46.8 ± 14.4 years) with episodic vertigo attacks of different etiology. D1 and D3 did not differ significantly concerning age, gender, the grade of ELH, or data quality. As an artificial data set, D2 provided a known ground truth and consisted of an 8-bit cuboid volume using the same voxel-size and grid as real-world data with different sized cylindrical and cuboid-shaped cutouts (signal) whose grayscale values matched the real-world data set D1 (mean 68.7 ± 7.8; range 48.9–92.8). The evaluation included segmentation accuracy using the Sørensen-Dice overlap coefficient and segmentation precision by comparing the volume of the ELS.

Results

VOLT resulted in a high level of performance and accuracy in comparison with the respective gold standard. In the case of the artificial data set, VOLT outperformed the gold standard in higher noise levels. Data processing steps are fully automated and run without further user input in less than 60 s. ELS volume measured by automatic segmentation correlated significantly with the clinical grading of the ELS (p < 0.01).

Conclusion

VOLT enables an open-source reproducible, reliable, and automatic volumetric quantification of the inner ears’ fluid space using MR volumetric assessment of endolymphatic hydrops. This tool constitutes an important step towards comparable and systematic big data analyses of the ELS in patients with the frequent syndrome of episodic vertigo attacks. A generic version of our three-dimensional thresholding algorithm has been made available to the scientific community via GitHub as an ImageJ-plugin.