Bilateral vestibulopathy with positive Tullio phenomenon

Rare Disorders of the Vestibular Labyrinth: of Zebras, Chameleons and Wolves in Sheep's Clothing

The differential diagnosis of vertigo syndromes is a challenging issue, as many - and in particular - rare disorders of the vestibular labyrinth can hide behind the very common symptoms of "vertigo" and "dizziness". The following article presents an overview of those rare disorders of the balance organ that are of special interest for the otorhinolaryngologist dealing with vertigo disorders. For a better orientation, these disorders are categorized as acute (AVS), episodic (EVS) and chronic vestibular syndromes (CVS) according to their clinical presentation. The main focus lies on EVS sorted by their duration and the presence/absence of triggering factors (seconds, no triggers: vestibular paroxysmia, Tumarkin attacks; seconds, sound and pressure induced: "third window" syndromes; seconds to minutes, positional: rare variants and differential diagnoses of benign paroxysmal positional vertigo; hours to days, spontaneous: intralabyrinthine schwannomas, endolymphatic sac tumors, autoimmune disorders of the inner ear). Furthermore, rare causes of AVS (inferior vestibular neuritis, otolith organ specific dysfunction, vascular labyrinthine disorders, acute bilateral vestibulopathy) and CVS (chronic bilateral vestibulopathy) are covered. In each case, special emphasis is laid on the decisive diagnostic test for the identification of the rare disease and "red flags" for potentially dangerous disorders (e. g. labyrinthine infarction/hemorrhage). Thus, this chapter may serve as a clinical companion for the otorhinolaryngologist aiding in the efficient diagnosis and treatment of rare disorders of the vestibular labyrinth.

Clinical characteristics in unilateral vestibular atelectasis

INTRODUCTION

Unilateral vestibular atelectasis (UVA), an entity first described by Merchant and Schuknecht in 1988, has rarely been reported in vivo as of yet. We specify here the clinical characteristics of 22 patients diagnosed with UVA.

MATERIALS AND METHODS

Patients with a radiological diagnosis of UVA who underwent delayed inner ear MRI were included between April 2017 and January 2020. Full clinical testing including ocular infrared video-oculography, oVEMPs, cVEMPs, vHIT, bithermal caloric testing and auditory testing was performed.

RESULTS

There were 13 men and 9 women, of mean age 58.6 ± 13.7 years. Onset was more frequently sudden (73%) than insidious (27%) though both clinical presentations were reported, and positional vertigo was described in 41% of cases. There were only two (9%) patients reporting Tullio's phenomenon. Vestibular testing showed that in 90% of cases, there was utricular dysfunction on oVEMP, while in 77% of cases, saccular function was preserved on cVEMP. vHIT showed high-velocity canal function impairment in all 22 patients: 8 patients (36%) had one impaired canal, 5 (23%) had two and 9 (41%) had all three canals affected. Caloric tests found complete unilateral areflexia, in 65% of tested cases, and partial deficiency in 35% of cases. Nine patients (40%) displayed asymmetrical hearing.

CONCLUSION

We described in this study the various clinical presentations of a disease rarely reported in vivo, UVA. Initial clinical presentation can appear similar to an acute vestibular deficit, a recurrent positional vertigo, or fluctuating dizziness.

Electrophysiological and inner ear MRI findings in patients with bilateral vestibulopathy

PURPOSE

Bilateral vestibulopathy (BV) is an uncommon disorder and the etiology remained idiopathic in most cases. Delayed 3D-FLAIR sequences have provided new insights into various inner ear diseases, allowing the evaluation of the endolymphatic space and the permeability of the blood-labyrinthine barrier (BLB). The aim of this study was to assess both the morphology of the endolymphatic space and the permeability of the BLB in patients with BV as evaluated by delayed 3D-FLAIR sequences.

METHODS

In this retrospective study, we performed 3D-FLAIR sequences 4 h after administering contrast media to 42 patients with BV. Two radiologists independently evaluated the morphology of the endolymphatic space (either vestibular atelectasis or endolymphatic hydrops) and the permeability of the BLB.

RESULTS

Morphologic anomalies of the endolymphatic space and vestibular blood-labyrinthine barrier impairment were observed in 59.6% of patients with BV. Bilateral vestibular atelectasis (VA) was found in 21 patients (50%), involving only the utricle and all three ampullas while the saccule was always observed with no sign of collapse: idiopathic BV (n = 19), aminoglycoside administration (n = 1) and few days following abdominal surgery (n = 1). One patient had bilateral vestibular malformation. BLB impairment was observed in five patients (11.9%): paraneoplastic (n = 1), lymphoma (n = 1), autoimmune (n = 1), and vestibular "neuritis" (n = 2). Seventeen patients (40.4%) had normal MRI with no endolymphatic space anomaly or BLB impairment.

CONCLUSION

Patients with BV presented with morphologic anomalies of the endolymphatic space or BLB impairment in 59.6% of patients.

Bilateral Vestibular Atelectasis with Tullio's Phenomenon

Vestibular dehiscence or atelectasis is a rarity known to cause vertigo. This pathology poses many challenges especially in diagnosis and treatment simply due to the scarcity of reported cases. The etiologic factors, disease pathophysiology and complications remain unclear. We report a young adult female who presented with unsteadiness for 2 years associated with headache. Tullio's phenomenon was observed which led to a finding of bilateral vestibular dehiscence involving the medial walls on high resolution computed tomography.

Full Spectrum of Reported Symptoms of Bilateral Vestibulopathy Needs Further Investigation-A Systematic Review

Objective

To systematically review the symptoms reported by patients with bilateral vestibulopathy (BV) in clinical studies and case reports. This would serve as the first step in establishing a validated patient-reported outcome measures (PROM) for BV.

Methods

A search on symptoms reported by patients with BV was performed in PubMed, and all publications covering these symptoms were included. Exclusion criteria comprised reviews and insufficient details about the frequency of occurrence of symptoms.

Results

1,442 articles were retrieved. 88 studies were included (41 clinical studies, 47 case reports). In consensus, 68 descriptions of symptoms were classified into 6 common and generic symptoms. Frequency of symptoms in clinical studies and case reports were reviewed, respectively; imbalance (91 and 86%), chronic dizziness (58 and 62%), oscillopsia (50 and 70%), and recurrent vertigo (33 and 67%). BV could be accompanied by hearing loss (33 and 43%) and tinnitus (15 and 36%). 15 clinical studies and 10 case reports reported symptoms beyond vestibular and hearing deficits such as limited social activities, depression, concentration, and memory impairment and reduced quality of life in general.

Conclusion

The literature on BV symptomatology mainly focuses on classic symptoms such as imbalance and oscillopsia, while only few report additional symptoms such as cognitive memory impairment and performing dual tasks. In fact, none of the reviewed clinical studies and case reports provided a comprehensive overview of BV symptoms. To develop a validated PROM, qualitative research using semi-structured and unstructured interviews is needed to explore the full spectrum of BV symptoms.