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

Abstract

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.

Dissociation of Caloric and Video Head Impulse Tests in Patients With Delayed Endolymphatic Hydrops

“…Our result was in agreement with that reported by Schuknecht et al who found that 80% of the ipsilateral DEH patients had unilateral caloric weakness in the hydropic ear and 9% had such hypofunction in the opposite ear (29). The substantially higher incidence of abnormal CP in the ear with precedent hearing loss than in the contralateral ear might be ascribed to the fact that: (1) bilateral ELH is commonly present in ipsilateral DEH patients, as demonstrated by gadolinium-enhanced MRI (30,31), and (2) the area of ELH in the deaf ear was significantly larger than or practically equivalent to that of the better-hearing ear (31).…”

“…In the present study, 50% (1/2) of the patients with contralateral DEH showed the abnormal CP and vHIT in the previously deaf ear rather than the opposite ear. The pattern of ELH distribution and vestibular deficit is rather complicated in contralateral DEH, indicating that its pathology is more involved compared to its ipsilateral counterpart (30,32,33). Further studies with larger sample sizes are warranted to elucidate the pathogenesis.…”

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

“…During the past two decades, high-resolution MRI with gadolinium as the contrast agent has been shown to provide direct evidence of ELH in the inner ear in vivo, which facilitates diagnosis of hydropic ear disease (MD, DEH, etc.) [50][51][52]. Meanwhile, non-enhanced MRI can also differentiate the endo-and perilymph space and is of great clinical value in detecting ELH in MD patients [53], although this statement was under debate [54].…”

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

“…Therefore, our data indicated that TSCP was less destructive theoretically by comparison with chemical labyrinthectomy. Iwasa et al 20 reported that in 19 cases of DEH, 6 patients were diagnosed with bilateral DEH (31.6%). So we should pay careful attention to this bilateral pathology and give priority to TSCP when compared with intratympanic gentamicin.…”