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

Role of conventional MD staging in modern era of hydrops MR imaging

Objective/Hypothesis

This study correlated stage of Meniere's disease (MD) with MR imaging of endolymphatic hydrops (EH) to assess the role of MD staging in modern era.

Study Design

Retrospective study.

Methods

Fifty-four MD patients (60 ears) underwent an inner ear test battery and were further confirmed by MR imaging. Sixty MD ears were divided into stages I-IV, and hydrops MR images at each stage were compared.

Results

Hydrops MRI demonstrated that EH at the cochlea with respective Grades 0/I/II were 3/7/1 ears for stage I, 0/5/3 ears for stage II, 1/6/26 ears for stage III and 0/2/6 ears for stage IV. Significant relationship was not identified between MD stage and grades of cochlear hydrops. Similarly, no significant relationship was shown between MD stage and grades of vestibular (saccular/utricular) hydrops. The optimal cutoff value of four-tone average for predicting severe type (Grade II-III) cochlear/vestibular EH was 48 dB, which was within the stage III. Hence, prevalence of severe type (Grade II) cochlear EH in stages III (79%) and IV (75%) was significantly higher than stages I (9%) and II (38%). Similarly, severe type saccular/utricular EH in stages III (64%) and IV (75%) also showed significantly higher than stages I (18%) and II (25%).

Conclusion

Although conventional MD staging fails to correlate with the grades of EH on hydrops MRI, late-stage MD may indicate heightened EH severity in the cochlea and vestibule.

Level of Evidence

4.

Multiple genetic variants involved in both autoimmunity and autoinflammation detected in Chinese patients with sporadic Meniere's disease: a preliminary study

Background

The mechanisms of Meniere's disease (MD) remain largely unknown. The purpose of this study was to identify possible genetic variants associated with immune regulation in MD.

Methods

The whole immune genome of 16 Chinese patients diagnosed with sporadic MD was sequenced using next-generation sequencing.

Results

Definite pathological variants of MEFV (c.1223G>A, c.1105C>T), COL7A1 (c.5287C>T), and ADA (c.445C>T) contributing to the clinical phenotype were found in three patients. Limited and likely pathological variants of TLR3 (c.2228G>A) and RAB27A (c.560G>A) were detected in one patient each. The following definite pathological variants impairing the structure and function of translated proteins were detected in 10 patients, and multigene variants occurred in five patients: PRF1 (c.710C>A), UNC13D (c.1228A>C), COLEC11 (c.169C>T), RAG2 (c.200G>C), BLM (c.1937G>T), RNF31 (c.2533G>A), FAT4 (c.11498A>G), PEPD (c.788A>G), TNFSF12 (c.470G>A), VPS13B (c.11972A>T), TNFRSF13B (c.226G>A), ERCC6L2 (c.4613A>G), TLR3 (c.2228G>A), ADA (c.445C>T), PEPD (c.151G>A), and MOGS (c.2470G>A). The following limited pathological variants impairing the structure and function of translated proteins were detected in five patients, with double gene variants identified in one patient: EXTL3 (c.1396G>A), MTHFD1 (c.2057G>A), FANCA (c.2039T>C), LPIN2 (c.1814C>T), NBAS (c.4049T>C), and FCN3 (c.734G>A).

Conclusion

Patients with sporadic MD carry multiple genetic variants involved in multiple steps of immune regulation, which might render patients susceptible to developing inflammation via both autoimmune and autoinflammation mechanisms upon internal stress.

Comparison between 3D SPACE FLAIR and 3D TSE FLAIR in Menière's disease

Purpose

Heavily T2-weighted 3D FLAIR (hT₂w-3D-FLAIR) sequence with constant flip angle (CFA) has been reported as being more sensitive to low concentrations of gadolinium (Gd) enabling endolymphatic hydrops (EH) visualization. The purpose of this study was to compare signal-to-noise (SNR) ratio, detection rate of EH, and increased perilymphatic enhancement (PE) as well as diagnostic accuracy in diagnosing definite Menière’s disease (MD), using 3D-SPACE FLAIR versus conventional 3D-TSE FLAIR.

Methods

This retrospective study included 29 definite MD patients who underwent a 4-h delayed intravenous (IV) Gd-enhanced 3D-TSE FLAIR and 3D-SPACE FLAIR MRI between February 2019 and February 2020. MR images were qualitatively and quantitatively analyzed twice by 2 experienced head and neck radiologists. Qualitative assessment included grading of cochlear and vestibular EH and visual comparison of PE. Quantitative assessment of PE was performed by placing a region of interest (ROI) and ratio calculation in the basal turn of the cochlea and the brainstem.

Results

The intra- and inter-reader reliability for grading of EH and PE was excellent (0.7 < kappa < 0.9) for 3D-SPACE FLAIR and exceeded the values for 3D-TSE FLAIR (0.5 < kappa < 0.9) The combination of EH and visual assessment of PE has the highest diagnostic accuracy in diagnosing definite MD on 3D-SPACE FLAIR with a sensitivity of 0.91 and a specificity of 0.98 resulting in a sensitivity raise of 6% compared to 3D-TSE FLAIR.

Conclusion

Four-hour delayed IV Gd-enhanced 3D-SPACE FLAIR sequence has a higher sensitivity and reproducibility than 3D-TSE FLAIR for the visualization of EH and increased PE in definite MD patients.

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

PURPOSE

Current studies show that frequency tuning modification is a good marker for the detection of endolymphatic hydrops (EH) employing magnetic resonance imaging (MRI) in patients with Ménière's disease (MD). The purpose of the present study is to analyze the auditory and vestibular function with audiometric and vestibular-evoked myogenic potentials (VEMP) responses, respectively, in both the affected and unaffected ears of patients with unilateral MD using MRI as diagnostic support for the degree of EH.

METHODS

We retrospectively reviewed the medical records of 76 consecutive patients with unilateral definite MD (age 55 (28-75); 39 women, 37 men). MRI was used through intravenous gadolinium administration, audiometry, and VEMPs. Functional tests were performed up to a week after the MRI. All were followed up one year after imaging utilizing clinical, auditory, and vestibular testing to rule out bilateral involvement.

RESULTS

In the unaffected ear, the mean pure-tone average is normal even in cases with hydrops and, for a similar severity of hydrops is significantly lower than in the affected ear. Significant differences for the amplitude of the response at 0.5 kHz, at 1 kHz between the affected and unaffected ears were found to be lower in the affected ears. The relative amplitude ratio (1 Kz-0.5 kHz) was significantly lower in the affected ear and in the case of the oVEMP response depends on the degree of EH. The response in the unaffected ear was not modified by the presence or the degree of hydrops.

CONCLUSION

In the unaffected ear, hydrops is not associated with hearing deterioration. For a similar degree of hydrops, hearing loss is significantly greater in the affected ear. The endolymphatic hydrops in the vestibule induces a frequency bias in the VEMP response only in the affected ear and not in the unaffected ear. Because of these findings we consider that hydrops does not represent an active disorder in the unaffected ear.