ORIGINAL PAPER
Nagoya J. Med. Sci. 85. 299–309, 2023
doi:10.18999/nagjms.85.2.299

Magnetic resonance imaging of endolymphatic hydrops:
a comparison of methods with and without
gadolinium-based contrast agent administration
Toshio Ohashi1,2, Shinji Naganawa3, Yusuke Nasu2,
Kayao Kuno4 and Katsuhiko Kato5
1

Department of Integrated Health Sciences, Nagoya University Graduate School of Medicine, Nagoya, Japan2
Department of Radiology, Kamiiida Daiichi General Hospital, Nagoya, Japan3
Department of Radiology, Nagoya University Graduate School of Medicine, Nagoya, Japan
4
Department of Otorhinolaryngology, Kamiiida Daiichi General Hospital, Nagoya, Japan
5
Functional Medical Imaging, Biomedical Imaging Sciences, Division of Advanced Information Health
Sciences, Department of Integrated Health Sciences, Nagoya University Graduate School of Medicine,
Nagoya, Japan

ABSTRACTIn the evaluation of endolymphatic hydrops (EH) using magnetic resonance (MR) imaging, hybrid ofreversed image of positive endolymph signal and native image of perilymph signal multiplied with heavily T2-weighted MR cisternography (HYDROPS-Mi2) imaging with the intravenous administration of agadolinium-based contrast agent (IV-GBCA) has been utilized. Recently, MR cisternography (MRC) without
GBCA has been proposed as a potential alternative method. However, the feasibility of EH evaluation
by MRC without GBCA has not been established. The present study aimed to compare HYDROPS-Mi2
imaging with IV-GBCA to MRC without IV-GBCA for the evaluation of EH. In 40 ears of 20 patientswith clinically suspected EH, MRC at pre-IV-GBCA and HYDROPS-Mi2 images from 4 h post-IV-GBCA
were analyzed. The saccular height on the MRC (SH-MRC) was measured. The percentage of the volumeof the endolymphatic space within the whole lymphatic space of the vestibule on the HYDROPS-Mi2
image (%ELvolume-HYD) was measured. The correlation between the SH-MRC and %ELvolume-HYD was
calculated. The receiver operating characteristic (ROC) of the SH-MRC and %ELvolume-HYD for the clinicaldiagnosis of EH was evaluated. The Spearman’s rank correlation coefficient between the SH-MRC and%ELvolume-HYD was 0.102. The areas under the ROC curve were 0.570 for the SH-MRC, and 0.926 for
the %ELvolume-HYD. In conclusion, there was no significant correlation between the MRC without IV-GBCA
and the HYDOROPS-Mi2 with IV-GBCA in the evaluation of EH.
Keywords: magnetic resonance imaging, gadolinium, endolymphatic hydrops, Meniere’s disease
Abbreviations:bSSFP: balanced steady-state free-precession

Received: June 1, 2022; accepted: July 6, 2022
Corresponding Authors: Toshio Ohashi, BS; Katsuhiko Kato, MD, PhD
Department of Radiology, Kamiiida Daiichi General Hospital, 2-70 Kamiiida-kitamachi, Kita-ku, Nagoya
462-0802, Japan (Ohashi);
Functional Medical Imaging, Biomedical Imaging Sciences, Division of Advanced Information Health
Sciences, Department of Integrated Health Sciences, Nagoya University Graduate School of Medicine, 1-1-20
Daiko-minami, Higashi-ku, Nagoya 461-8673, Japan (Kato)
Tel: +81-52-991-3111 (Ohashi); +81-52-719-1590 (Kato), Fax: +81-52-981-6879 (Ohashi); +81-52-719-1589(Kato), E-mail: oohashi.toshio.x7@s.mail.nagoya-u.ac.jp (Ohashi); katokt@med.nagoya-u.ac.jp (Kato)
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EH: endolymphatic hydrops
FLAIR: fluid-attenuated inversion recovery
GBCA: gadolinium-based contrast agent
hT2w: heavily T2-weighted
HYDROPS: HYbriD of Reversed image Of Positive endolymph signal and native image of positive
perilymph Signal
HYDROPS-Mi2: HYDROPS-Multiplied with hT2w MRC
IV: intravenous administration
MR: magnetic resonance
MRC: MR cisternography%ELvolume-HYD: percentage of the volume of the endolymphatic space within the whole lymphatic spaceof vestibule measured on HYDROPS-Mi2
ROC: receiver operating characteristic
ROI: region of interest
SH-MRC: saccular height on MRC
3D: three-dimensional
This is an Open Access article distributed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International
License. To view the details of this license, please visit (http://creativecommons.org/licenses/by-nc-nd/4.0/).

INTRODUCTION
Meniere’s disease is a neurological disorder of the inner ear with symptoms that include
attacks of vertigo, hearing loss, tinnitus, and aural fullness.1 Endolymphatic hydrops (EH) in the
inner ear has been considered as a pathological finding of Meniere’s disease.1 The presence of
EH has been clinically evaluated using magnetic resonance (MR) imaging after the intravenous
administration of a gadolinium-based contrast agent (IV-GBCA).1-3 Intravenously administered
GBCAs cross the blood-perilymph barrier, but do not cross the blood-endolymph and perilymphendolymph barriers.4 The amount of intravenously administered GBCA that penetrates into theperilymph is too small to detect using conventional T1-weighted imaging. 2,5 A heavily T2weighted three-dimensional fluid-attenuated inversion recovery (hT2w-3D-FLAIR) sequence candetect subtle T1 shortening such as in fluid with very small concentrations of GBCA, and hence
has been applied for the evaluation of EH with MR imaging.3,5 A HYbriD of Reversed image
Of Positive endolymph signal and native image of positive perilymph Signal (HYDROPS) and a
HYDROPS-Mi2 (HYDROPS-Multiplied with hT2w MRC) sequence enables separate visualizationof the endolymph, perilymph, and surrounding bony structures.6,7 This separate visualization of
the endo- and perilymph reduces the difficulty of the EH evaluation.2,6,7 A Nakashima grade has
been proposed as the criterion for the diagnosis of EH on MR imaging.8 A quantitative evaluationof the endolymphatic space by volumetric measurement has also been reported.9 MR imaging
with GBCA administration has thus been applied clinically for the qualitative and quantitativeevaluation of EH.1,2,8,9
Recently, several studies for the evaluation of EH using MR imaging without GBCA administration have been reported.10-12 They have proposed that MR cisternography (MRC) permits
the direct evaluation of the vestibular endolymphatic space through anatomical identification.10-12
One of the studies suggested that the utricular endolymph has a lower signal intensity than thevestibular perilymph on MRC without IV-GBCA.10 The other studies assessed vestibular EH by
measuring the height and width of the saccule on MRC without IV-GBCA.11,12 The saccule wasdefined as the region bounded by the utricular macula and the lateral membranous walls of thesaccule for the measurement of the saccular size.11,12
The evaluation of EH using MRC without GBCA administration has clinical implications. In
our hospital, we routinely perform the evaluation of EH at 4 h post-IV-GBCA administration, andNagoya J. Med. Sci. 85. 299–309, 2023

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EH evaluation with and without IV-GBCA

prior to the IV-GBCA, we obtain an MRC as the anatomical reference image. When our reviewing the MRC, we were able to distinguish the utricular macula, however the lateral membranous
wall of the saccule or the vestibular endolymph was unclear. At least, there did not seem tobe any displacement of the utricular macula in our MRC with or without EH. Therefore, wehypothesized that an MRC without GBCA might not be suitable to evaluate the endolymphatic
space. To our knowledge, there are no reports directly comparing EH evaluation methods withand without IV-GBCA. The purpose of present study was to compare the evaluation of EH using
HYDROPS-Mi2 (with IV-GBCA) and MRC (without IV-GBCA).

MATERIALS AND METHODSPatients and materials
Forty ears from consecutive 20 patients with clinically suspected EH who underwent MR
imaging from November, 2017 through November, 2018 were enrolled in the present study (men:9, women: 11, ages: 21 to 70-year-old, median: 53.5-year-old). The patient with severe motion
artifact was an exclusion criterion. The estimated glomerular filtration rate of all patients at
pre-administration of GBCA exceeded 60 ml/min/1.73m2. The medical ethics committee of ourinstitution approved this retrospective cross-sectional study with a waiver of written informed
consent from the patients (2021-0461). The present study was conducted in compliance with
the Declaration of Helsinki in 1964 and its later amendments. All MR imaging was performed
using a 3-tesla MR scanner (MAGNETOM Skyra; Siemens Healthcare, Erlangen, Germany) witha 32-channel phased-array head coil. The contrast agent administered to patients in the present
study was a macrocyclic GBCA (Gd-HP-DO3A: ProHance; Eisai, Tokyo, Japan). A single doseof GBCA defined as 0.1 mmol/kg body-weight was administered. A DICOM viewer (OsiriX
version 5.8 32 bit; Pixmeo SARL, http://www.osirix-viewer.com/) was used for image processing
and analysis. Statistical analyses were performed with free statistical software (R software version
3.6.1; The R Foundation, https://www.r-project.org/).
MR imaging
MRC and hT2w-3D-FLAIR images were obtained. All imaging sequences were based on
hT2w-3D-fast spin echo imaging with a variable refocusing flip angle. The cross section of theslab for all imaging was the axial plane parallel to the anterior commissure - posterior commissure line and through the bilateral internal auditory canal in the axial plane. The slab center of
all imaging was set at the level of the internal auditory canal. At pre-IV-GBCA, MRC of thewhole lymphatic space was obtained for anatomical reference. A repetition time of 2500 ms,
echo time of 400 ms, voxel size of 0.50 × 0.50 × 0.5 mm, and slab thickness of 80 mm wereapplied. At 4 h post-IV-GBCA, MRC, hT2w-3D-FLAIR with an inversion time of 2250 ms as
the positive perilymph image, and hT2w-3D-FLAIR with an inversion time of 2050 ms as the
positive endolymph image were obtained to generate the HYDROPS-Mi2 image. The parameters
were set according to a previously reported study.6 A repetition time of 4400 ms for the MRC, arepetition time of 9000 ms for the positive perilymph image and positive endolymph image, anecho time of 544 ms, voxel size of 0.51 × 0.51 × 1.0 mm, and a slab thickness of 104 mm wereapplied. The detailed parameters of all imaging are summarized in Table 1. The HYDROPS-Mi2
images were generated according to the previous study as follows.7   HYDROPS = positive perilymph image - positive endolymph image   HYDROPS-Mi2 = HYDROPS × MRC
On the HYDROPS-Mi2 images, no misregistration artifacts greater than 1 mm were confirmed
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Table 1

Pulse sequence parameters

Pre-IV-GBCA

4 h Post-IV-GBCA

MRC

MRC

positive
perilymph image

positive
endolymph image

Pulse sequence type

SPACE

SPACE

SPACE withinversion pulse

SPACE withinversion pulse

Repetition time/Echotime (ms)2500 / 400

4400 / 544

9000 / 544

9000 / 544

Inversion time (ms)

NA

NA

2250

2050

Band width (Hz/Px)

422

434

434

434

Flip angle (degree)

90 / initial 180
decrease toconstant 120

90 / initial 180
decrease toconstant 120

90 / constant 180

90 / constant 180

Echo train length

181

173

173

173

Matrix

320 × 320

324 × 384

324 × 384

324 × 384

Slice thickness (mm) /Slices0.5 / 80

1.0 / 104

1.0 / 104

1.0 / 104

Resolution (mm)0.50 × 0.50

0.51 × 0.51

0.51 × 0.51

0.51 × 0.51

Field of view (mm)160 × 160

196 × 165

196 × 165

196 × 165

Parallel imaging /Accel. factor

GRAPPA / 2

GRAPPA / 2

GRAPPA / 2

GRAPPA / 2

Fat saturation

NA

CHESS

CHESS

CHESS

Number of excitations

1.5

1.8

2

2

Acquisition time (min)

5.2

3.3

7.4

7.4

CHESS: chemical shift selective saturation
GRAPPA: generalized auto-calibrating partially parallel acquisition
IV-GBCA: intravenous administration of gadolinium-based contrast agent
MRC: magnetic resonance cisternography
NA: not applicable
SPACE: sampling perfection with application-optimized contrasts using different flip angle evolutionsin any patients.
Image analysis
A clinical diagnosis of EH had been made by an experienced neuroradiologist (SN) subjectively, according to the Nakashima grade.8
Two radiological technologists with 18 years (TO) and 8 years (YN) of experience in MR
imaging performed all image analyses. The distance between the utricular macula and thevestibular edge of the osseous spiral lamina was measured as the saccular height on the MRC(SH-MRC) obtained at pre-IV-GBCA. The measurement protocol was described below.
1. The MRC was reformatted to the coronal plane perpendicular to the anterior commissureposterior commissure line.
2. The reformatted coronal image through the inferior vestibular nerve was used for the measurement.
3. The distance between the middle of the utricular macula and the vertically inferior osseous
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EH evaluation with and without IV-GBCA

spiral lamina was measured.
The SH-MRC ie, the shift of the utricular macula, was regarded as an indicator of thedegree of vestibular EH using MRC without IV-GBCA in the present study. An example of themeasurement of the SH-MRC is indicated in Fig. 1.
The percentage of the volume of the endolymphatic space within the whole lymphatic spaceof the vestibule was measured on the HYDROPS-Mi2 images (%ELvolume-HYD), according topreviously a reported study.9
1. The regions of interest (ROIs) were manually drawn along the boundary of the vestibule
excluding the ampulla of the semicircular canal on all slices of the MRC obtained at 4 h
post-IV-GBCA.
2. The ROIs of the MRC were copied and pasted onto the HYDROPS-Mi2 image.
3. The number of voxels in all ROIs represented the whole-lymph volume and were counted on
the HYDROPS-Mi2 image.
4. The number of voxels with a negative signal intensity in all ROIs represented the endolymph
volume and were counted on the HYDROPS-Mi2 image.
5. The %ELvolume-HYD was calculated as follows.
%ELvolume-HYD = (endolymph volume/whole lymph volume) × 100
The %ELvolume-HYD was regarded as an indicator of the degree of vestibular EH with IVGBCA in the present study.

Fig. 1 An example of the measurement of the saccular height
Magnetic resonance cisternography was reformatted to the coronal plane perpendicular to the anterior commissureposterior commissure line (dotted line) (a). The reformatted coronal images through the inferior vestibular nerve
were used for the measurement (b). The distance between the middle of the utricular macula (short arrow) andthe vertically inferior osseous spiral lamina (long arrow) was measured as the saccular height (line).

Statistical analyses
The inter-observer reliability was evaluated using an intraclass correlation coefficient (2, 1).
The averaged value from the two observers was used for the statistical analyses. The correlation
between the SH-MRC and %ELvolume-HYD was evaluated by a Spearman’s rank correlation coefficient. The receiver operating characteristic (ROC) curve of the SH-MRC and %ELvolume-HYD
were plotted to assess the consistency of the SH-MRC and %ELvolume-HYD compared to our
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Toshio Ohashi et al

clinical diagnosis of EH by the Nakashima grade using the area under the ROC curve. The ears
were classified into EH-negative and EH-positive groups using a cut-off value determined by the
maximum value of the Youden index of the ROC curve of the %ELvolume-HYD. A Mann-Whitney
U test was used to compare the SH-MRC between the EH-negative and EH-positive groups. We
defined 5% as a threshold for statistical significance.

RESULTS
There were no patients with severe motion artifact that would be an exclusion criterion. The
intraclass correlation coefficients (2, 1) between the measurements of the two observers were0.900 for the SH-MRC and 0.979 for the %ELvolume-HYD. There was no significant correlation
between the SH-MRC and %ELvolume-HYD (Fig. 2). The Spearman’s rank correlation coefficient
between the SH-MRC and %ELvolume-HYD was 0.102 (P = 0.532). In the ROC analysis for the
SH-MRC, the area under the ROC curve was 0.570 (95% confidence level: 0.378-0.762) (Fig.
3a). In the ROC analysis for the %ELvolume-HYD, the area under the ROC curve was 0.926 (95%
confidence level: 0.850-1.000) (Fig. 3b). The maximum value of the Youden index analyzed by

Fig. 2 Relationship between SH-MRC and %ELvolume-HYD
Scatterplots of the degree of endolymphatic hydrops showing the relationship between the SH-MRC without an
IV-GBCA and the %ELvolume-HYD with IV-GBCA. There was no significant correlation between the SH-MRC
and %ELvolume-HYD. The Spearman’s rank correlation coefficient between the SH-MRC and %ELvolume-HYD was
0.102 (P = 0.532).
IV-GBCA: intravenous administration of gadolinium-based contrast agent
percentage of the volume of the endolymphatic space within the whole lymphatic space of%ELvolume-HYD: vestibule measured on HYbriD of Reversed image Of Positive endolymph signal and native
image of positive perilymph Signal-Multiplied with heavily T2-weighted magnetic resonancecisternography
SH-MRC: saccular height on magnetic resonance cisternography
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EH evaluation with and without IV-GBCA

Fig. 3 Diagnostic performance of SH-MRC and %ELvolume-HYD
ROC curve for the clinical diagnosis of EH from the SH-MRC without an IV-GBCA (a), and the %ELvolume-HYD
with IV-GBCA (b). In the ROC analysis for the SH-MRC, the area under the ROC curve was 0.570 (95%
confidence level: 0.378-0.762), for the %ELvolume-HYD, the area under the ROC curve was 0.926 (95% confidence
level: 0.850-1.000). The maximum value of the Youden index analyzed by the ROC curve of %ELvolume-HYD
was 23.5 (sensitivity: 92.9%, specificity: 80.8%).
EH: endolymphatic hydrops
IV-GBCA: intravenous administration of gadolinium-based contrast agent
percentage of the volume of the endolymphatic space within the whole lymphatic space of%ELvolume-HYD: vestibule measured on HYbriD of Reversed image Of Positive endolymph signal and native
image of positive perilymph Signal-Multiplied with heavily T2-weighted magnetic resonancecisternography
ROC: receiver operating characteristic
SH-MRC: saccular height on magnetic resonance cisternography
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the ROC curve of the %ELvolume-HYD was 23.5 (sensitivity: 92.9%, specificity: 80.8%). The
number of ears divided by the cut-off value was 14 ears in the EH-negative group and 14
ears in the EH-positive group. The median of the SH-MRC was 3.48, with a range of 2.62 to
4.22 in the EH-negative group. The median of the SH-MRC was 3.59, with a range of 3.13 to
4.11 in the EH-positive group. There was no significant difference in the SH-MRC between the
EH-negative and EH-positive groups (P = 0.478) (Fig. 4). Representative images obtained in thepresent study are indicated in Fig. 5.

Fig. 4 Comparison between the SH-MRC of the EH-negative and EH-positive groups
A box-and-whisker plot showing the SH-MRC without an intravenous administration of gadolinium-based contrast
agent in the EH-negative group and EH-positive groups. The lower side of the rectangle shows the first quartile(25th percentile value) and the upper side is the 75th percentile value. The thick horizontal line in the rectangle
shows the median. The horizontal line under the whisker indicates the 10th percentile value, and the horizontal
line above the whisker shows the 90th percentile value. There was no significant difference in the SH-MRC
between EH-negative and EH-positive groups (P = 0.478).
EH: endolymphatic hydrops
SH-MRC: saccular height on magnetic resonance cisternography

DISCUSSION
In the present study, highly reproducible results between the two observers were found in boththe SH-MRC without IV-GBCA and the %ELvolume-HYD with IV-GBCA. There was no significant
correlation between the SH-MRC without IV-GBCA and the %ELvolume-HYD with IV-GBCA. The%ELvolume-HYD with IV-GBCA showed higher agreement to our clinical diagnosis of EH using
the Nakashima grade compared to the SH-MRC without IV-GBCA. There was no difference in
the SH-MRC without IV-GBCA between the EH-negative and EH-positive groups.
A method to evaluate EH by the lateral membranous wall of the saccule on MRC without
IV-GBCA has been reported.11,12 The MRC in these studies was acquired using a balanced
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EH evaluation with and without IV-GBCA

Fig. 5 Representative images with and without EH
Representative images from a 37-year-old man with no EH; MRC obtained at pre- IV-GBCA (a); a HYDROPSMi2 image obtained at 4 h post-IV-GBCA (b), and a 55-year-old woman with significant EH; MRC obtained at
pre-IV-GBCA (c); a HYDROPS-Mi2 image obtained at 4 h post-IV-GBCA(d). Black areas in HYDROPS-Mi2
images (short arrows, b, d) indicate endolymphatic space. There was no displacement of the utricular macula(long arrows) due to the presence of EH.
EH: endolymphatic hydrops
HYDROPS-Mi2: HYbriD of Reversed image Of Positive endolymph signal and native image of positive perilymph
Signal-Multiplied with heavily T2-weighted MRC
IV-GBCA: intravenous administration of gadolinium-based contrast agent
MRC: magnetic resonance cisternographysteady-state free-precession (bSSFP) sequence.11,12 The bSSFP sequence has a risk of a banding
artifact with low signal due to the B0 field inhomogeneity.13 Previously reported studies havesuggested that a fast spin echo sequence without banding artifact is more appropriate than thebSSFP sequence for MRC of the inner ear imaging.14,15 Recently, a machine learning-based trial toautomatically diagnose Meniere’s disease by training the differences of imaging findings between
patients with Meniere’s disease and controls on MRC without IV-GBCA was reported.16 Because
the fast spin echo-based MRC and bSSFP-based MRC were mixed in their study,16 a concern
about the bias for their results due to low-signal banding artifacts of bSSFP-based MRC has been
mentioned.17 A previous study compared a bSSFP-based MRC without IV-GBCA to a 3D-FLAIR
with IV-GBCA for the evaluation of EH.18 In that study, the degree of EH assessed by the MRC
was less specific for Meniere’s disease symptoms than that obtained with the 3D-FLAIR images.18
Additionally, a poor inter-rater agreement was reported for the measurement of the saccular size
using MRC without IV-GBCA in that study.18 Since the membrane separating the endolymph andperilymph is much thinner than the resolution of routine clinical MR imaging (0.5 × 0.5 × 0.5
mm in this study),1,19 the lateral membranous wall of the saccule would be obscured by partial
volume effects. The structures, which were thought to be the lateral membranous walls of saccule
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Toshio Ohashi et alin these studies,11,12,18 might be banding artifacts associated with the bSSFP sequence. Because
we were actually unable to clearly distinguish the lateral membranous wall of the saccule using
the MRC based on a fast spin echo sequence, we measured the distance between the utricularmacula and the osseous spiral lamina in the present study. There was no displacement of theutricular macula due to the presence of EH. Therefore, we concluded that MRC without IV-GBCA
is not suitable for the evaluation of EH.
A previously reported study suggested that vestibular EH had a lower signal intensity thanthe perilymph on MRC without IV-GBCA.10 However, it has also been reported that a differencein the fluid-composition between the endo- and perilymph was insufficient to produce enoughcontrast to visualize individually the endo- and perilymph on MRC without IV-GBCA.2,20 In some
exceptions, the endolymphatic spaces have been visualized on MR imaging without IV-GBCA. 21-23
The endolymph had a higher signal intensity than the perilymph on 3D-FLAIR images without
IV-GBCA for a condition in which the endolymph contained blood components.21 With enlarged
endolymphatic sac and duct syndrome, the endolymph of the inner ear receives an influx of
fluid containing highly proteinaceous or hemorrhagic components from the endolymphatic sac,and can have a high signal intensity on 3D-FLAIR images.22 In contrast, it has been reported
that the perilymphatic space had a higher signal intensity than the endolymphatic space in noncontrast 3D-FLAIR images in cases of vestibular schwannoma.23 Outside of these exceptions, itis necessary to produce contrast between the endo- and perilymphatic spaces by IV-GBCA, forvisualization of EH.
The present study has a few limitations. A small number of patients were evaluated. The
drawing of the ROI was performed manually, although measurements from two observers
indicated high agreement. The cochlear endolymph was not evaluated. Since the cochlear duct
is a small structure compared to the saccule,1 it was considered that cochlear endolymph could
not be visualized with MRC.

CONCLUSION
There was no significant correlation between the MRC without GBCA administration and the
HYDOROPS-Mi2 with GBCA administration in the evaluation of EH. It was concluded that
MRC without GBCA administration cannot apply for accurate evaluation of the degree of EH.

DISCLOSURE STATEMENT
None of the authors have any conflicts of interest regarding the present study.

REFERENCES
1
2

3
4

Nakashima T, Pyykkö I, Arroll MA, et al. Meniere’s disease. Nat Rev Dis Primers. 2016;2:16028.
doi:10.1038/nrdp.2016.28.
Naganawa S, Nakashima T. Visualization of endolymphatic hydrops with MR imaging in patients with
Ménière’s disease and related pathologies: current status of its methods and clinical significance. Jpn JRadiol. 2014;32(4):191–204. doi:10.1007/s11604-014-0290-4.
Naganawa S. The Technical and Clinical Features of 3D-FLAIR in Neuroimaging. Magn Reson Med Sci.
2015;14(2):93–106. doi:10.2463/mrms.2014-0132.
Nakashima T, Naganawa S, Teranishi M, et al. Endolymphatic hydrops revealed by intravenous
gadolinium injection in patients with Ménière’s disease. Acta Otolaryngol. 2010;130(3):338–343.

Nagoya J. Med. Sci. 85. 299–309, 2023

308

doi:10.18999/nagjms.85.2.299

EH evaluation with and without IV-GBCA

5

6

7

8
9

10
11

12

13
14

15

16

17

18

19
20
21

22
23

doi:10.1080/00016480903143986.
Naganawa S, Kawai H, Sone M, Nakashima T. Increased sensitivity to low concentration gadolinium
contrast by optimized heavily T2-weighted 3D-FLAIR to visualize endolymphatic space. Magn Reson Med
Sci. 2010;9(2):73–80. doi:10.2463/mrms.9.73.
Naganawa S, Yamazaki M, Kawai H, Bokura K, Sone M, Nakashima T. Imaging of Ménière’s disease after
intravenous administration of single-dose gadodiamide: utility of subtraction images with different inversion
time. Magn Reson Med Sci. 2012;11(3):213–219. doi:10.2463/mrms.11.213.
Naganawa S, Suzuki K, Nakamichi R, et al. Semi-quantification of endolymphatic size on MR imaging after
intravenous injection of single-dose gadodiamide: comparison between two types of processing strategies.
Magn Reson Med Sci. 2013;12(4):261–269. doi:10.2463/mrms.2013-0019.
Nakashima T, Naganawa S, Pyykko I, et al. Grading of endolymphatic hydrops using magnetic resonanceimaging. Acta Otolaryngol Suppl. 2009;(560):5–8. doi:10.1080/00016480902729827.
Naganawa S, Ohashi T, Kanou M, Kuno K, Sone M, Ikeda M. Volume quantification of endolymph after
intravenous administration of a single dose of gadolinium contrast agent: comparison of 18- versus 8-minuteimaging protocols. Magn Reson Med Sci. 2015;14(4):257–262. doi:10.2463/mrms.2014-0118.
Keller JH, Hirsch BE, Marovich RS, Branstetter BF 4th. Detection of endolymphatic hydrops using
traditional MR imaging sequences. Am J Otolaryngol. 2017;38(4):442–446. doi:10.1016/j.amjoto.2017.01.038.
Simon F, Guichard JP, Kania R, Franc J, Herman P, Hautefort C. Saccular measurements in routine MRI
can predict hydrops in Menière’s disease. Eur Arch Otorhinolaryngol. 2017;274(12):4113–4120. doi:10.1007/
s00405-017-4756-8.
Venkatasamy A, Veillon F, Fleury A, et al. Imaging of the saccule for the diagnosis of endolymphatichydrops in Meniere disease, using a three-dimensional T2-weighted steady state free precession sequence:
accurate, fast, and without contrast material intravenous injection. Eur Radiol Exp. 2017;1(1):14. doi:10.1186/
s41747-017-0020-7.
Scheffler K, Lehnhardt S. Principles and applications of balanced SSFP techniques. Eur Radiol.
2003;13(11):2409–2418. doi:10.1007/s00330-003-1957-x.
Naganawa S, Koshikawa T, Fukatsu H, Ishigaki T, Fukuta T. MR cisternography of the cerebellopontine
angle: comparison of three-dimensional fast asymmetrical spin-echo and three-dimensional constructive
interference in the steady-state sequences. AJNR Am J Neuroradiol. 2001;22(6):1179–1185.
Kojima S, Suzuki K, Hirata M, Shinohara H, Ueno E. Depicting the semicircular canals with inner-ear
MRI: a comparison of the SPACE and TrueFISP sequences. J Magn Reson Imaging. 2013;37(3):652–659.
doi:10.1002/jmri.23863.
van der Lubbe MFJA, Vaidyanathan A, de Wit M, et al. 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. Radiol Med. 2022;127(1):72–82. doi:10.1007/s11547-021-01425-w.
Naganawa S, Ito R, Taoka T, Yoshida T, Sone M. Letter to editor on the article “A non-invasive, automateddiagnosis of Menière’s disease using radiomics and machine learning on conventional magnetic resonanceimaging: a multicentric, case-controlled feasibility study” by van der Lubbe Mfja et al. Radiol Med.
2022;127(4):458–459. doi:10.1007/s11547-022-01486-5.
Eliezer M, Poillon G, Horion J, et al. MRI diagnosis of saccular hydrops: comparison of heavily-T2 FIESTAC and 3D-FLAIR sequences with delayed acquisition. J Neuroradiol. 2021;48(6):446–452. doi:10.1016/j.
neurad.2019.04.005.
Ito T, Naganawa S, Fukatsu H, et al. High-resolution MR images of inner ear internal anatomy using a
local gradient coil at 1.5 Tesla: correlation with histological specimen. Radiat Med. 1999;17(5):343–347.
Pyykkö I, Zou J, Poe D, Nakashima T, Naganawa S. Magnetic resonance imaging of the inner ear in
Meniere’s disease. Otolaryngol Clin North Am. 2010;43(5):1059–1080. doi:10.1016/j.otc.2010.06.001.
Naganawa S, Ishihara S, Iwano S, Sone M, Nakashima T. Detection of presumed hemorrhage in the ampullar
endolymph of the semicircular canal: a case report. Magn Reson Med Sci. 2009;8(4):187–191. doi:10.2463/
mrms.8.187.
Naganawa S, Sone M, Otake H, Nakashima T. Endolymphatic hydrops of the labyrinth visualized on
noncontrast MR imaging: a case report. Magn Reson Med Sci. 2009;8(1):43–46. doi:10.2463/mrms.8.43.
Naganawa S, Kawai H, Sone M, Nakashima T, Ikeda M. Endolympathic hydrops in patients with vestibular
schwannoma: visualization by non-contrast-enhanced 3D FLAIR. Neuroradiology. 2011;53(12):1009–1015.
doi:10.1007/s00234-010-0834-y.

References End

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