A perilymphatic fistula (PLF) presents with abnormal traffic in the otic capsule, causing cochlear and vestibular symptoms. However, the mechanisms underlying symptom recurrence remain controversial. Herein, we report the case of a 27-year-old female who complained of hearing disturbance in her right ear and recurrent vertigo after sudden onset of hearing loss with vertigo. The caloric test revealed unilateral weakness in the right ear, and the video head impulse test (vHIT) showed decreased vestibulo-ocular reflex (VOR) gain. Contrast-enhanced magnetic resonance imaging (MRI) using hybrid of reversed image of positive endolymph signal and negative image of perilymph signal (HYDROPS) indicated a collapsed endolymphatic space. As the vestibular symptoms did not improve, an exploratory tympanotomy was performed on the right ear. Although perilymph leakage was not noted in the oval or round windows, both windows were sealed with connective tissue. The patient's vestibular symptoms rapidly improved after surgery, and postoperative contrast-enhanced MRI showed improvement in the collapsed endolymphatic space. Although the caloric test revealed unilateral weakness, the VOR gain on the vHIT improved to normal on the right side. Thus, these findings indicated that recurrent symptoms caused by PLF are associated with a collapsed endolymphatic space. We speculate that the collapsed endolymphatic space was due to a ruptured Reissner's membrane. We hypothesized that sealing the fistula would promote normalization of perilymph pressure. The ruptured Reissner's membrane may have been gradually repaired as vestibular symptoms improved. This case adds to the existing literature on the occurrence of the “double-membrane break syndrome”. Collapse of the endolymph due to a ruptured Reissner's membrane may be the cause of PLF symptoms.

Background/Objectives: Migraine is frequently comorbid with Meniere’s disease, which may complicate interpretation of inner ear imaging and clinical diagnosis. While endolymphatic hydrops has been studied in Meniere’s disease and vestibular migraine separately, comparative imaging data for Meniere’s disease patients with and without migraine remain limited. Methods: We retrospectively analyzed 78 patients with definite Meniere’s disease who underwent endolymphatic contrast-enhanced MRI (HYbriD of Reversed image of Positive endolymph signal and native image of positive perilymph signal; or “HYDROPS”). Patients were classified as Meniere’s disease only group (n = 56), or Meniere’s disease with migraine (n = 22). The degree of endolymphatic hydrops (negative, mild, or significant) was assessed separately in the inner ear, the cochlea, and the vestibule. Results: In Meniere’s disease group, the affected ear consistently showed higher rates of significant endolymphatic hydrops compared to the healthy ear across the inner ear, cochlea, and vestibule (p < 0.01). In contrast, Meniere’s disease with migraine group showed no significant interaural differences. Meniere’s disease with migraine group showed a significantly higher frequency of significant endolymphatic hydrops in the healthy cochlea (p < 0.01). Similar patterns were observed in the inner ear (p < 0.025) and vestibule (p = 0.05), although these differences did not reach statistical significance. Bilateral hydrops was significantly more frequent in Meniere’s disease with migraine group than in Meniere’s disease group among all regions investigated (p < 0.05). Conclusions: Meniere’s disease patients with migraine exhibit a distinct endolymphatic hydrops pattern, characterized by bilateral or symmetrical hydrops and involvement of the healthy ear. These findings suggest migraine-related mechanisms may contribute to endolymphatic hydrops, and bilateral endolymphatic hydrops on endolymphatic contrast-enhanced MRI in suspected Meniere’s disease cases should prompt consideration of comorbid migraine, in addition to bilateral Meniere’s disease or asymptomatic hydrops.

Hypothesis: Dysbiosis of the intestinal microflora has been reported in stress-induced depression and irritable colitis, a similar abnormality may also occur in stress-triggered Meniere’s disease. Background: Meniere’s disease is an intractable disease characterized by paroxysms of intense rotatory dizziness, hearing loss, and other auditory symptoms. It is believed to be caused by endolymphatic hydrops of the vestibule and cochlea. The diagnosis of Meniere’s disease is based on the diagnostic criteria established by the Barany Society and AAO-HNS and Journal of Vestibular Research as definite or probable cases. Endolymphatic hydrops identification using cochlear contrast-enhanced MRI (hybrid of reversed image of positive endolymph signal and native image of positive perilymph signal [HYDROPS]) is an objective test for Meniere’s disease, enabling reliable diagnosis of this disease. Methods: We investigated the gut microbiota of 10 patients (6 males and 4 females, mean age 49.6 ± 8.1 years) who met the diagnostic criteria for a unilateral definite case of Meniere’s disease using the diagnostic criteria of the Journal of Vestibular Research, and who also had significant endolymphatic hydrops on the affected side on HYDROPS. Intestinal microbiota tests were performed on these 10 patients and the results were evaluated in relation to the duration of disease, results of audiometry of the affected side, and DHI (Dizziness Handicap Inventory) score. Results: A significant negative correlation was found between the disease duration and Shannon diversity index and Faith’s phylogenetic diversity, which indicated dysbiosis of the intestinal microflora. No correlation was found between the indicators of microbial diversity and the results of audiometry or the DHI on the affected side. Dysbiosis of the intestinal microbiota worsened with increasing duration of Meniere’s disease. Moreover, Akkermansia muciniphila was not detected in any patient with Meniere’s disease. Conclusions.: Despite the small number of cases in this study (n = 10), the findings indicate the possibility of abnormalities of the intestinal microflora in Meniere’s disease.