Saccular measurements in routine MRI can predict hydrops in Menière’s disease

A novel radiomics nomogram based on T2-sampling perfection with application-optimized contrasts using different flip-angle evolutions (SPACE) images for predicting cochlear and vestibular endolymphatic hydrops in Meniere's disease patients

OBJECTIVES

To construct and validate a radiomics nomogram based on T2-sampling perfection with application-optimized contrasts using different flip-angle evolutions (SPACE) images for predicting cochlear and vestibular endolymphatic hydrops (EH) in Meniere's disease patients.

METHODS

A total of 156 patients (312 affected ears) with bilateral definite Meniere's disease who underwent delayed enhancement MRI scans were enrolled in this study. All ears of the patients were divided into a training set (n = 218) and an internal validation set (n = 94). A radiomics nomogram was constructed from radiomics features extracted from the T2-SPACE images, and a radiomics score was calculated. Performance of the radiomics nomogram was assessed using receiver operating characteristics analysis.

RESULTS

Five features were selected for the construction of the cochlear radiomics nomogram, and seven features for the vestibular radiomics nomogram. The radiomics nomograms exhibited robust performance in differentiating between EH-positive and EH-negative statuses in both training and validation cohorts, with the area under the receiver operating characteristics curve values for cochlear and vestibular radiomic nomograms being 0.703 and 0.728 in the training set, and 0.718 and 0.701 in the validation set, respectively.

CONCLUSION

The novel radiomics nomograms based on T2-SPACE images were successfully constructed to predict cochlear and vestibular EH in Meniere's disease. The models showed a solid and superior performance and may play an important role in the EH prediction.

CLINICAL RELEVANCE STATEMENT

We constructed a novel radiomics nomogram, which can be a very useful tool for predicting cochlear and vestibular endolymphatic hydrops in Meniere's disease patients.

KEY POINTS

• This is the first T2-SPACE-based nomogram to predict cochlear and vestibular endolymphatic hydrops. • The nomogram is of great value to patients who are unable to undergo delayed enhancement MRI scans.

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.

Finite Element Modeling of Residual Hearing after Cochlear Implant Surgery in Chinchillas

Cochlear implant (CI) surgery is one of the most utilized treatments for severe hearing loss. However, the effects of a successful scala tympani insertion on the mechanics of hearing are not yet fully understood. This paper presents a finite element (FE) model of the chinchilla inner ear for studying the interrelationship between the mechanical function and the insertion angle of a CI electrode. This FE model includes a three-chambered cochlea and full vestibular system, accomplished using µ-MRI and µ-CT scanning technologies. This model's first application found minimal loss of residual hearing due to insertion angle after CI surgery, and this indicates that it is a reliable and helpful tool for future applications in CI design, surgical planning, and stimuli setup.

Detailed insight into magnetic resonance assessment of Ménière's disease - description of methodology and imaging findings in a case series

Purpose

The study aimed to describe the methodology and detailed interpretation of magnetic resonance imaging (MRI) in patients with Ménière’s disease (MD).

Material and methods

MRIs were performed on a 3T scanner. The three-dimensional fluid-attenuated inversion recovery (3D-FLAIR) sequence 4 hours after a double dose of intravenous contrast was added to the standard MRI protocol in patients with clinically diagnosed MD. MRI findings of 7 patients with unilateral MD were analysed using 2 qualitative grading systems by Barath and Bernaerts.

Results

In MRI, the following changes in the group of patients with MD were observed: lack of endolymphatic hydrops (cases #1 and #7), various grades of cochlear hydrops (cases #2 and #3), various grades of vestibular hydrops (cases #4, #5, and #6), endolymphatic hydrops herniation into the semi-circular canal (case #6), and more robust perilymphatic enhancement (case #7).

Conclusions

In patients with MD, endolymphatic hydrops can be studied on MRI using 3D-FLAIR delayed post-contrast images. The qualitative grading system may be easily used in endolymphatic hydrops assessment. Recently described new radiological signs of MD such as increased perilymphatic enhancement of the cochlea and an extra low-grade VH may increase MD diagnosis sensitivity. MRI not only supports the clinical diagnosis of MD but also may help to understand its pathophysiology.

Visualization of the saccule and utricle with non-contrast-enhanced FLAIR sequences

OBJECTIVES

3D-fluid attenuation inversion recovery (FLAIR) collected 4 h after intravenous gadolinium injection can delineate the perilymphatic space (PLS) from the endolymphatic space (ELS) to capture endolymphatic hydrops, the pathological counterpart of Ménière's disease. We aimed to optimize visualization of such inner ear internal anatomy using 3D-FLAIR without injection.

METHODS

3D-FLAIR signal from different fluid compartments such as PLS and ELS was first simulated. Then, twenty-two healthy subjects were scanned at 3.0-T MRI with non-injected 3D-FLAIR using variable T2 preparations (T2Preps) (OFF, 200, 400, and 600 ms) and variable inversion times (TIs) (from 224 to 5000 ms) and different resolutions (1.0 × 1.0 × 1.5, 0.6 × 0.6 × 0.8, and 0.6 × 0.6 × 0.6 mm³). The relative contrast between PLS and ELS and the visibility of the saccule and utricle were assessed. Additionally, non-injected 3D-FLAIR with the optimal setting was tested in a Ménière patient and compared with gadolinium-injected 3D-FLAIR.

RESULTS

The PLS and ELS were differentiated when T2Prep was used but not without. The relative contrast was larger with T2Prep at 400 ms than at 200 or 600 ms (0.72 ± 0.22 vs. 0.44 ± 0.11, p = 0.019; and 0.72 ± 0.22 vs. 0.46 ± 0.28, p = 0.034, respectively). The saccule and utricle were best delineated in 87. % cases with T2Prep = 400 and TI = 2100 ms at the highest resolution. Visualization of the saccule and utricle in the optimized non-injected 3D-FLAIR was similar to conventional injected 3D-FLAIR in a patient.

CONCLUSIONS

Combining a specific T2Prep and TI in non-injected 3D-FLAIR could separate PLS and ELS and even the saccule and utricle, paving the way toward future application to diagnose Ménière's disease.

KEY POINTS

• MRI can capture the internal anatomy of inner ear without injection of contrast media. • Specific parameters consisting of a T2 preparation of 400 ms and an inversion time of 2100 ms must be used to visualize the saccule and utricle on non-injected 3D-FLAIR.

A non-invasive, automated diagnosis of Menière's disease using radiomics and machine learning on conventional magnetic resonance imaging: A multicentric, case-controlled feasibility study

Purpose

This study investigated the feasibility of a new image analysis technique (radiomics) on conventional MRI for the computer-aided diagnosis of Menière’s disease.

Materials and methods

A retrospective, multicentric diagnostic case–control study was performed. This study included 120 patients with unilateral or bilateral Menière’s disease and 140 controls from four centers in the Netherlands and Belgium. Multiple radiomic features were extracted from conventional MRI scans and used to train a machine learning-based, multi-layer perceptron classification model to distinguish patients with Menière’s disease from controls. The primary outcomes were accuracy, sensitivity, specificity, positive predictive value, and negative predictive value of the classification model.

Results

The classification accuracy of the machine learning model on the test set was 82%, with a sensitivity of 83%, and a specificity of 82%. The positive and negative predictive values were 71%, and 90%, respectively.

Conclusion

The multi-layer perceptron classification model yielded a precise, high-diagnostic performance in identifying patients with Menière’s disease based on radiomic features extracted from conventional T2-weighted MRI scans. In the future, radiomics might serve as a fast and noninvasive decision support system, next to clinical evaluation in the diagnosis of Menière’s disease.

Supplementary Information

The online version contains supplementary material available at 10.1007/s11547-021-01425-w.

Present and future of the labyrinth imaging: Focus on the use of T2-weighted and contrast-enhanced delayed FLAIR (1 h) sequences

OBJECTIVE

Part of the recent progress in the labyrinth imaging has been made possible by the rise of contrast-free T2-weighted and delayed (1h) FLAIR sequences. The aim of this article is to review evidence for the use of these two sequences to image the inner ear, especially the posterior membranous labyrinth.

MATERIAL AND METHODS

We analyzed MRI-based papers (2007-2020)using high-resolution T2-weighted or contrast-enhanced FLAIR (1h) sequences to image the inner ear.

RESULTS

T2-weighted sequences (3T MRI)enabled the visualization of the posterior membranous labyrinth with good correlation when compared to corresponding histological slices.Significant progress has been made, especially in terms of scanning time, aiming at reducing it, in order to decrease motions artifacts. The saccule is visible on a 3T MRI without significant motion artifacts. Its shape is ovoid, with a maximum height and width of 1.6 and 1.4 mm, respectively. An enlarged saccule was observed in 84%of patients with unilateral Meniere's disease, in 28%of patients with vestibular schwannomas (VS) and 47%of patients with intralabyrinthine schwannomas. VS obstructing the internal auditory canal caused a decrease of the perilymphatic signal (more moderate decrease in meningiomas) on T2 gradient-echo images. Contrast-enhanced FLAIR sequences are useful to image vestibular/facial neuritis and inflammatory inner ear diseases.

CONCLUSION

Precise analysis of the posterior membranous labyrinth, in terms of size, shape and signal intensity, is possible on a 3T MRI using high-resolution gradient-echo T2-weighted sequences. Such sequences are an interesting add-on to delayed (4h30) FLAIR-based protocols for labyrinth imaging.

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.

Endolymphatic hydrops magnetic resonance imaging in Ménière's disease

This review is designed to help radiologists interested in developing a magnetic resonance imaging service for patients with symptoms of Ménière's disease. Examples are selected from our experience with delayed post-gadolinium three-dimensional (3D) fluid attenuated inversion recovery (FLAIR) inner ear imaging of endolymphatic hydrops. The imaging features of the normal and hydropic endolymphatic structures, semiquantitative grading systems, normal variations, and differential diagnoses will be illustrated, whilst appropriate clinical referrals, approaches to reporting and diagnostic pitfalls will be discussed.

MRI of endolymphatic hydrops in patients with intralabyrinthine schwannomas: a case-controlled study using non-enhanced T2-weighted images at 3 T

OBJECTIVE

Like other vestibular schwannomas developing in the internal auditory canal, intralabyrinthine schwannomas (ILS) may present with similar symptoms as in endolymphatic hydrops. Two different studies have described MR saccular hydrops in ~ 30% of internal auditory canal vestibular schwannomas, but this association has never been studied in ILS before. The aim of this work is to study the prevalence of a saccular dilation in ILS, on a T2-weigthed sequence at 3 T, compared to a control group.

MATERIAL AND METHODS

All patients presenting with typical ILS between January 2008 and October 2018 were included (n = 28, two patients with bilateral tumors) and compared to a control group (n = 53). All underwent a high-resolution T2-weighted 3D sequence (FIESTA-C). The height and width of the saccule were measured on a coronal plane by two radiologists.

RESULTS

The saccule was dilated on the side of the schwannoma in 47% of the cases (p = 0.0006 for the height, p = 0.0487 for the width). Bilateral saccular dilation was observed in 37% of the cases. There was a statistically significant correlation between the presence of a saccular hydrops and balance disorders (p = 0.02) as 50% of the patients with an intralabyrinthine schwannoma who presented with such symptoms had a saccular dilation.

CONCLUSION

Forty-seven percent of ILS are associated with homolateral saccular dilation, which is an MR sign of endolymphatic hydrops (bilateral in 37%) and it appears related to the presence of balance disorders. This opens new therapeutic potentialities with the possible use of anti-vertiginous drugs, which could have a beneficial effect on their clinical symptomatology.

Magnetic resonance imaging of Ménière's disease: early clinical experience in a UK centre

BACKGROUND

Recent developments in magnetic resonance imaging have enabled demonstration of endolymphatic hydrops, and the clinical application of these imaging studies in Ménière's disease is being explored.

OBJECTIVE

To evaluate our centre's experience to date of hydrops magnetic resonance imaging in patients with episodic vertigo.

METHODS

Magnetic resonance imaging was performed using a high-resolution three-dimensional fluid-attenuated inversion recovery sequence on a 3 Tesla scanner at 4 hours following double-dose gadolinium administration.

RESULTS

The study included 31 patients, 28 of whom had a clinical diagnosis of Ménière's disease. In unilateral Ménière's disease, magnetic resonance imaging was able to lateralise endolymphatic hydrops to the clinically symptomatic ear in all cases. Mild hydrops was often seen in clinically asymptomatic ears.

CONCLUSION

There is a good correlation between the clinical symptoms and lateralisation of hydropic changes on magnetic resonance imaging. Further refinements of imaging techniques and grading system will likely improve the diagnostic accuracy and clinical utilisation of hydrops magnetic resonance imaging.

MRI of endolymphatic hydrops in patients with vestibular schwannomas: a case-controlled study using non-enhanced T2-weighted images at 3 Teslas

OBJECTIVE

Vestibular schwannomas (VS) may present with similar symptoms endolymphatic hydrops. Association between hydrops and internal auditory canal VS has been described by Naganawa et al. (Neuroradiology 53:1009-1015, 2011), but has never been confirmed since. The aim of this work was to study the prevalence of a saccular dilation on a T2-weighted sequence at 3 T MRI in VS compared to a control group.

MATERIALS AND METHODS

All patients presenting with typical VS between May 2009 and July 2018 were included (n = 183) and compared to a control group (n = 53). All underwent a high-resolution T2-weighted 3D sequence (FIESTA-C). The height and width of the saccule were measured on a coronal plane by two radiologists.

RESULTS

The saccule was dilated on the side of the schwannoma in 28% of the cases (p = 2.81 × 10^- 5), with 15.7% of bilateral dilation. Saccular dilation was correlated to sensorineural hearing loss (OR 3.26, p = 0.02). There was also a significant correlation between saccular hydrops on the normal contralateral side of patients with VS and vertigo (p = 0.049), and between saccular hydrops on the side of the tumour and tinnitus (p = 0.006).

CONCLUSION

A third (29%) of VS are associated with a saccular dilation on the side of the tumour, which is an MR sign of endolymphatic hydrops (bilateral in 15.7% of the cases) and it appears related to sensorineural hearing loss and tinnitus, as well as vertigo if a contralateral dilation is present. This opens new therapeutic potentialities with the use of anti-vertiginous drugs, which could have a beneficial effect on the clinical symptoms.

Imaging of Ménière Disease

Visualization of the morphologic substrate of Ménière disease, the endolymphatic hydrops, can be performed using noncontrast or contrast-enhanced MR imaging techniques. Noncontrast MR imaging uses a heavily T2-weighted sequence; however, its reproducibility remains to be confirmed. Contrast-enhanced MR imaging techniques mainly use a 3-dimensional fluid-attenuated inversion recovery sequence after intratympanic gadolinium administration or after a 4-hour delayed intravenous gadolinium administration. The latter technique is most frequently used and is able to detect and grade Ménière disease. It is a reliable technique with a high diagnostic accuracy, enabling visualization of endolymphatic hydrops.

The value of four stage vestibular hydrops grading and asymmetric perilymphatic enhancement in the diagnosis of Menière's disease on MRI

Purpose

There is still a clinical-radiologic discrepancy in patients with Menière’s disease (MD). Therefore, the purpose of this study was to investigate the reliability of current MRI endolymphatic hydrops (EH) criteria according to Baráth in a larger study population and the clinical utility of new imaging signs such as a supplementary fourth low-grade vestibular EH and the degree of perilymphatic enhancement (PE) in patients with Menière’s disease (MD).

Methods

This retrospective study included 148 patients with probable or definite MD according to the 2015 American Academy of Otolaryngology, Head and Neck Surgery criteria who underwent a 4-h delayed intravenous Gd-enhanced 3D-FLAIR MRI between January 2015 and December 2016. Vestibular EH, vestibular PE, cochlear EH, and cochlear PE were reviewed twice by three experienced readers. Cohen’s Kappa and multivariate logistic regression were used for analysis.

Results

The intra- and inter-reader reliability for the grading of vestibular-cochlear EH and PE was excellent (0.7 < kappa < 0.9). The two most distinctive characteristics to identify MD are cochlear PE and vestibular EH which combined gave a sensitivity and specificity of 79.5 and 93.6%. By addition of a lower grade vestibular EH, the sensitivity improved to 84.6% without losing specificity (92.3%). Cochlear EH nor vestibular PE showed added-value.

Conclusions

MRI using vestibular-cochlear EH and PE grading system is a reliable technique. A four-stage vestibular EH grading system in combination with cochlear PE assessment gives the best diagnostic accuracy to detect MD.

Detection of intralabyrinthine abnormalities using post-contrast delayed 3D-FLAIR MRI sequences in patients with acute vestibular syndrome

PURPOSE

3D-FLAIR sequences with delayed acquisition after contrast medium injection have demonstrated new insights into blood-labyrinthine barrier (BLB) abnormalities in various diseases. The aim of this study was to assess the BLB in patients referred with unilateral acute vestibular syndrome (UAVS).

MATERIALS AND METHODS

In this retrospective multicenter imaging study, we performed 3D-FLAIR and steady-state free precession (SSFP) sequences 4 h after contrast medium administration in 26 healthy volunteers and in 30 patients with UAVS. Two radiologists, blinded to the clinical data, independently assessed the asymmetrical enhancement of the labyrinthine structures and the vestibular nerve on 3D-FLAIR sequences, and the signal of the labyrinthine structures on SSFP sequences. Inter-reader agreement tests were performed.

RESULTS

An asymmetrical enhancement of the semicircular canals was observed in 26 out of 30 ears (86.6%, p < 0.001) and never observed in healthy subjects. An asymmetrical enhancement of the vestibular nerve was never observed in either patients or healthy subjects. An asymmetrical enhancement of the cochlea was observed on the 3D-FLAIR sequence in 6 out of 30 ears only in the patients' group (20%, p = 0.03) and always associated with an enhancement of at least one semicircular canal. A low signal on SSFP sequences was observed only in 11 out of 30 symptomatic ears (36.7%, p < 0.001), involving the utricle in 7 ears and the superior semicircular canal in 4 ears.

CONCLUSION

Patients with typical UAVS presented with semicircular canal enhancement on MRI, while an asymmetrical enhancement of the vestibular nerve was not displayed.

TRIAL REGISTRATION

NCT02529475 KEY POINTS: • Patients with typical vestibular neuronitis presented with semicircular canal enhancement on MRI in 87% of cases. • An enhancement of the vestibular nerve was never displayed.