Diagnostic value of three-dimensional magnetic resonance imaging of inner ear after intratympanic gadolinium injection, and clinical application of magnetic resonance imaging scoring system in patients with 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.

Different findings of morphological changes and functional decline in the vestibule and the semicircular canal in ipsilateral delayed endolymphatic hydrops

OBJECTIVE

To elucidate the pathophysiological process by analyzing the correlation between morphological and functional changes in patients with delayed endolymphatic hydrops (DEH).

METHODS

Twenty-nine patients diagnosed with DEH were enrolled in this retrospective study. All patients were assessed using the caloric test, cervical and ocular vestibular evoked myogenic potentials, and gadolinium-enhanced magnetic resonance imaging (MRI) of the inner ear.

RESULTS

According to the MRI, the hydrops localization was categorized as hydrops in the vestibule (saccule and utricle) (14%), hydrops in the vestibule and cochlea (72%), and hydrops in the vestibule, cochlea, and lateral semicircular canal (LSCC) (14%). Vestibular hydrops could definitely be observed as function declined; however, a dysfunction of both the saccule and utricle was not always present when vestibular hydrops was detected with MRI. In the LSCC, a decline in functional tests was not necessarily accompanied by morphological abnormalities. However, dysfunction could definitely be detected when LSCC hydrops was observed with MRI.

CONCLUSIONS

Hydrops can be found mainly in the vestibule as shown by MRI. In the vestibule, abnormalities are commonly morphologic rather than functional, whereas in the LSCC a functional deterioration can be detected more frequently than morphological changes.

SIGNIFICANCE

Our findings can provide a new perspective on the functional and morphological characteristics of patients with DEH.

Bilateral delayed endolymphatic hydrops evaluated by bilateral intratympanic injection of gadodiamide with 3T-MRI

The purpose of this study was to assess the diagnostic performance of 3T MRI after intratympanic injection of gadodiamide for delayed endolymphatic hydrops (DEH), and assess the relationship between endolymphatic hydrops (ELH) and vestibular function in patients diagnosed with DEH and confirmed by 3T MRI. Nineteen patients clinically diagnosed with DEH (11 ipsilateral DEH, 8 contralateral DEH) participated in this study. Diluted gadodiamide was administered to the bilateral tympanic cavity by injection through the tympanic membrane. At 24 hours post-injection, the ELH was evaluated by MRI. Patient vestibular functions were evaluated by caloric testing and cVEMP. ELH was observed in all patients (19/19: positive rate 100%). The distribution patterns of ELH varied between the cochlear or vestibular region. Vestibular ELH was observed in the affected ear in all ipsilateral DEH patients. In the contralateral DEH patients, however, there were individual differences in the distribution patterns of ELH. Six patients (1 ipsilateral DEH, 5 contralateral DEH) had bilateral ELH. No obvious relationships were observed between ELH and vestibular function. ELH distribution was complicated, particularly in the contralateral DEH cases. It was difficult to identify the existence of ELH by vestibular functional testing alone; therefore, 3T MRI is thought to be useful for identifying the affected ear. A significant number of cases had “bilateral” DEH, particularly among the contralateral DEH cases, indicating that we should pay careful attention to this pathology when treating DEH.

Preceding profound deafness and co-factors promote development of endolymphatic hydrops in preliminary patients with delayed endolymphatic hydrops

CONCLUSION

Profound deafness (PD) is unlikely to be the only cause of endolymphatic hydrops (EH) in patients with delayed endolymphatic hydrops (DEH). Further studies in large patient cohorts are required to determine the etiologic co-factors involved in the development of EH in patients with PD and DEH.

OBJECTIVES

DEH usually occurs in patients with sustained unilateral PD who then develop episodic vertigo or fluctuating hearing loss. The latency can vary markedly between PD and development of DEH, but the factors affecting inner ear homeostasis and causing EH during this latency period remain unclear. The study aimed to assess the differences in EH and functional status of the inner ear between patients with PD only and those with DEH.

METHOD

Two PD and 10 DEH patients who had developed PD in early childhood were enrolled. Gadolinium-enhanced magnetic resonance imaging of the inner ear was performed in all patients to assess the degree of EH in the vestibule and cochlea.

RESULTS

There was no evidence of EH in the affected ears of patients with PD alone. DEH patients, however, showed significant EH in either the cochlea or vestibule, suggesting that EH development and DEH onset were strongly correlated.