Three-Dimensional Magnetic Resonance Imaging Reveals the Relationship Between the Control of Vertigo and Decreases in Endolymphatic Hydrops After Endolymphatic Sac Drainage With Steroids for Meniere's Disease

Abstract

Meniere's disease is a common disease, that presents with recurrent vertigo and cochlear symptoms. The pathology of Meniere's disease was first reported to involve endolymphatic hydrops in 1938. The endolymphatic sac is thought to have a role to keep the hydrostatic pressure and endolymph homeostasis for the inner ear. As a surgery for intractable Meniere's disease, endolymphatic sac drainage with intraendolymphatic sac application of large doses of steroids is performed to control the endolymphatic hydrops and preserve or improve inner ear function. In the present study, to observe the effect of this surgery, we calculated the endolymphatic space size using 3-Tesla magnetic resonance imaging (MRI) 4 h after intravenous injection of gadolinium enhancement at two time points: just before surgery and 2 years after. To reveal the condition of the endolymphatic space, we constructed three-dimensional MR images semi-automatically and fused the three-dimensional images of the total fluid space of inner ear and the endolymphatic space. After fusing the images, we calculated the volume of the total fluid space and endolymphatic space. Two years after surgery, 16 of 20 patients (80.0%) showed relief from vertigo/dizziness and reductions in the ratio of the volume of the endolymphatic size to the total fluid space of inner ear. Endolymphatic sac drainage with intraendolymphatic sac application of large doses of steroids could control vertigo/dizziness and decrease the endolymphatic hydrops. These results indicate that endolymphatic sac drainage is a good treatment option for patients with intractable Meniere's disease. In addition, volumetric measurement of inner ear volume could be useful for confirming the effect of treatments on Meniere's disease.

Differences between endolymphatic duct blockage and endolymphatic sac drainage surgery in the reversal of endolymphatic hydrops in patients with Meniere’s disease, preliminary results

“…In the present study, all 3 patients in the EDB group for whom reversal of EH was con rmed were found to have improved hearing, revealing a cause-effect relationship between EH and hearing function. However, with the 4 patients in the EDD group for whom reversal of EH was con rmed, hearing improved in only one patient, worsened in one, and was stabilized in the other two, suggesting no correlation between the changes in hearing function and the volume of EH after sac drainage surgery, a nding that was consistent with previous reports [26][27][28]. In the former case (EBD), the reversal of EH was found to be a delayed effect associated with the surgery that progressed over time, which was likely to be linked with physiological recovery in the homeostasis of the endolymph.…”

“…As presented in Figs. 2-5, the MRI technique used in the present study had an equal or superior resolution to other techniques reported in previous literature [14,15,[26][27][28]. The comparison of serial MRI scans, which were obtained from multiple section planes in the same ear between the before and after treatment, could clearly identify the dynamic changes of EH, showing an objective marker for assessing the effects of treatment in MD.…”

“…By contrast, EDD is based on the hypothesis that de cient absorption in the endolymphatic sac is one of the causes of EH, regardless of all other uncertainties surrounding the treatment of MD [23,24]. Endolymphatic sac drainage is still universally considered by surgeons to be an excellent option for vertigo control and hearing preservation [25]; moreover, a decrease in the volume of EH following sac drainage surgery has recently been con rmed with Gd-MRI [26][27][28]. However, the reversal of EH achieved in certain patients with MD via the two opposing surgical approaches on the endolymphatic sac, as investigated in the present study, has demonstrated the inhomogeneity and complexity of the mechanisms underpinning the development of EH.…”

Modulation of hearing function following the downgrading or upgrading of endolymphatic hydrops in Meniere’s disease patients with endolymphatic duct blockage

“…Recently, Ito et al reported a positive correlation between the control of vertigo and the decrease in the volume of EH, and no correlation between changes in the hearing function and the volume of EH following sac drainage surgery [ 46 , 47 ]. Higashi-Shingai et al also described that the presence of vestibular EH and the frequency of vertigo attacks significantly decreased following surgery, but no significant improvement in the presence of cochlear EH or the SP/AP ratio of ECochG was observed [ 48 ].…”

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

“…Currently only a few reports on the visualization of EH after treatment have been published. Subsiding of EH has recently been described after oral acetazolamide, IT corticosteroids, and endolymphatic sac surgery [91][92][93]. However, Gürkov et al found no effect of standard-dose oral betahistine on the degree of EH during a 7-month followup period [94].…”