Anatomical variation of inner ear may be a predisposing factor for unilateral Ménière’s disease rather than for ipsilateral delayed endolymphatic hydrops

Objective Radiological anatomical variations, measured by magnetic resonance imaging (MRI), were evaluated in patients with ipsilateral delayed endolymphatic hydrops (DEH) and unilateral Ménière’s disease (MD). The role of anatomical variations in different subtypes of hydropic ear disease was investigated. Methods Twenty-eight patients with ipsilateral DEH, 76 patients with unilateral MD, and 59 control subjects were enrolled. The radiological indices included the distance between the vertical part of the posterior semicircular canal and the posterior fossa (MRI-PP distance) and the visibility of vestibular aqueduct (MRI-VA). These variations among patients with DEH, MD, and control subjects were compared. The correlation between radiological anatomical variations and clinical features or audio-vestibular findings was also examined. Results (1) MRI-PP distance in the affected side of unilateral MD was shorter than that in ipsilateral DEH (Z = − 2.481, p = 0.013) and control subjects (Z = − 2.983, p = 0.003), while the difference of MRI-PP distance between the affected side of ipsilateral DEH and control subjects was not statistically significant (Z = − 0.859, p = 0.391). (2) There was no significant interaural difference of MRI-PP distance in patients with unilateral MD (Z = − 0.041, p = 0.968) and ipsilateral DEH (t = − 0.107, p = 0.915) respectively. (3) No significant interaural difference of MRI-VA visibility was observed in patients with unilateral MD (χ2 = 0.742, p = 0.389) and ipsilateral DEH (χ2 = 0.327, p = 0.567) respectively. (4) No correlation was found between these anatomical variables and clinical features or audio-vestibular findings in patients with unilateral MD and ipsilateral DEH respectively (p > 0.05). Conclusions Anatomical variations of inner ear may be a predisposing factor in the pathogenesis of unilateral MD rather than ipsilateral DEH. Key Points • Patients with ipsilateral delayed endolymphatic hydrops showed normal distance between the vertical part of the posterior semicircular canal and the posterior fossa. • Compared to patients with ipsilateral delayed endolymphatic hydrops and control subjects, patients with unilateral Ménière’s disease exhibited shorter distance between the vertical part of the posterior semicircular canal and the posterior fossa. • Anatomical variations of inner ear may be a predisposing factor in the pathogenesis of unilateral Ménière’s disease rather than ipsilateral delayed endolymphatic hydrops.

Evaluation of Patients with Delayed Endolymphatic Hydrops by Videonystagmography, Vestibular-Evoked Myogenic Potentials, and Electrocochleography

Introduction: The categorization of delayed endolymphatic hydrops (DEH) based on the ear which produces vertigo may sometimes cause misdiagnosis. Objectives: The aim of this study was investigating the vestibular-evoked myogenic potentials (VEMPs), electrocochleography (ECoG), and videonystagmography (VNG) in cases with DEH to determine the ear that originates symptoms. Methods: In this cross-sectional study, 34 patients – 20 males and 14 females – with profound unilateral sensorineural deafness and vertigo attacks were recruited and evaluated by the ECoG, VNG, and VEMPs tests. Results: The average age was around 43; the summating potential/action potential was abnormal in 29.4% of patients in their normal auditive ear. In 32.4, 17.6, and 50% of cases with a deaf ear, absent, normal, and abnormal VEMPs results were sequentially observed, respectively. In normal-hearing ears, absent, normal, and abnormal VEMPs were observed in 23.5, 50, and 26.5%, respectively. In the normal-hearing ear, the distribution of abnormal VEMPs was 26.5%, and in the deaf ear, this parameter was abnormal in 50% of the opposite ear (p value = 0.00021). In the VNG test, among patients with a normal-hearing ear, results in 27 and 7 patients were sequentially normal and hypofunction. Conclusion and Significance: The probability of a hypofunction VNG test in a normal-hearing ear might be greater when the VEMPs results of the contralateral deaf ear are normal. In patients with a normal-hearing ear, the distribution of abnormal VEMPs in the contralateral deaf ear is greater, although the intact side may also manifest abnormality in VEMPs tests. The initial evaluation should begin in a deaf ear as well as for the normal-hearing ear ere utilizing ablation surgery.

Long-term efficacy of triple semicircular canal plugging in the treatment of patients with ipsilateral delayed endolymphatic hydrops

This study aims to explore the long-term efficacy of triple semicircular canal plugging (TSCP) in the treatment of intractable ipsilateral delayed endolymphatic hydrops (DEH), so as to provide an alternative therapy for this disease. Forty-eight patients diagnosed with ipsilateral DEH referred to vertigo clinic of our hospital between Dec. 2010 and Dec. 2017, were included in this study for retrospective analysis. All patients were followed up for 2 years. Vertigo control and auditory functions were measured and analyzed. Pure tone audiometry, caloric test, and vestibular evoked myogenic potential (VEMP) were performed in two-year follow-up. Forty-five patients who accepted intratympanic gentamicin (26.7 mg/mL) twice given one week apart were selected as a control group. The total control rate of vertigo in TSCP group was 97.9% (47/48) in the two-year follow-up, with complete control rate of 83.3% (40/48) and substantial control rate of 14.6% (7/48). The rate of hearing loss was 22.9% (11/48). The total control rate of vertigo in intratympanic gentamicin group was 80.0% (36/45), with complete control rate of 57.8% (26/45) and substantial control rate of 22.2% (10/45), and the rate of hearing loss was 20.0% (9/45). The vertigo control rate of TSCP was significantly higher than that of intratympanic gentamicin (χ2 = 6.01, p < 0.05). There was no significant difference of hearing loss rate between two groups. (χ2 = 0.12, p > 0.05). TSCP, which can reduce vertiginous symptoms in patients with intractable ipsilateral DEH, represents an effective therapy for this disorder.