Vestibular atelectasis (VA)
Timothy C. Hain, MD • Page last modified:
March 5, 2021
|Normal labyrinth -- blue area is endolymph. Surrounding is perilymph.
Vestibular atelectasis is an obscure syndrome, mainly documented by case reports or pathological findings. The basic idea is that the membranous labyrinth consists of two compartments, the perilymph (outer), and the endolymph (inner). The inner compartment resembles a balloon that is suspended within the outer bony labyrinth. In vestibular atelectasis the walls of the labyrinth, potentially including the ampullae and utricle have collapsed. This was first described by Merchant and Schuknecht (1988) in autopsy specimens. They stated that "The principal clinical symptom is chronic unsteadiness, precipitated or aggravated by head movement, and sometimes associated with short episodes of spinning vertigo. It is presumed that the collapsed membranes interfere with the motion mechanics of the cupulae and otolithic membranes. "
Several papers and recent case reports have suggested (without proof) that the combination of bilateral vestibular weakness and pressure sensitivity is caused by vestibular atelectasis.
- Nadol (1995) stated that "The site of lesion, as evaluated by clinical signs and symptoms, is controversial because concomitant central nervous system abnormalities have been described. The histopathology of temporal bones from persons who in life had symptoms characteristic of vestibular neuritis demonstrates degeneration of branches of the vestibular nerve and the neuroepithelium of vestibular end organs. " This seems a bit vague.
- Acierno et al (1997) reported on a single patient, without pathology. They wrote "A patient with an idiopathic bilateral vestibulopathy described two types of oscillopsia, one induced by head movement, the other induced by changing pressure in the right external auditory canal."
- Kawaguchi et al (2010) reported that vestibular atelectasis was seen on autopsy of mutant guinea pigs, called "waltzing" guinea pigs.
- Vianna et al (2013) reported a single human case with bilateral vestibular hypofunction. They said "In this case, the otopathology demonstrated vestibular atelectasis of the membranous labyrinth of the superior, lateral, and posterior semicircular canals but not the utricle or saccule bilaterally.". So in other words, there was a selective collapse of the labyrinth of the semicircular canals, but not of the utricle or saccule.
- Wenzel et al (2014), without any pathological or anatomic confirmation, proposed that vestibular atelectasis might account for the combination of bilateral vestibular loss as well as pressure induced eye movements.
- Crane (2015) discussed that perhaps VA could be account for patients with sound sensitivity but lacking SCD.
- Kaski et al (2015) had similar comments as did Crane, and also opined that "we believe that further clinic-pathological correlation is required to substantiate the proposal that the Tullio phenomenon with horizontal sound/pressure-induced nystagmus, bilateral vestibular hypofunction, and normal audiometry relates to VA."
- Finn et al (2018) reported a single case similar to those of Vianna et al (2013). Again, no anatomic confirmation.
- Maslova (2018) reported another case similar to those of Vianna (2013), again without any anatomic confirmation.
- Eliezer et al (2019) reported that they could document VA on 3T MRI. They stated that of the 200 patients where they found this on MRI, "We reported four patients with VA on MRI responsible for atypical clinical presentations of acute vestibular deficit. All patients presented a specific involvement of the pars superior sensory captors (utricle, ampullas), preserving the pars inferior sensory captors (cochlea and saccule). This was confirmed both clinically and on MRI. CONCLUSIONS: Our study is the first to describe in vivo unilateral collapse of the pars superior on delayed postcontrast MRI in patients with a clinical unilateral vestibular loss."
- Eliezer et al (2020) reported on a subset of patients -- those who had no visualization of saccule (NVS) on delayed 3T MRI. They reported "Results: We reported on 28 patients with NVS. Among this group, on the NVS affected side: 14 had isolated sensorineural hearing loss (SNHL); 4 had fluctuating cochleo-vestibular disease; 3 had definite Meni?re's disease; 3 had Minor syndrome; 2 had delayed endolymphatic hydrops (EH); 2 had inner ear malformations; 1 had sudden cochleo-vestibular deficit following stapes surgery; 1 had a perilymphatic fistula and 1 had a contralateral fluctuating SNHL. Sixteen out of these 28 patients (57.1%) had cochlear hydrops on the same side as the NVS, while 10 patients (35.7%) had saccular hydrops on the contralateral side. Moreover, isolated blood labyrinth barrier (BLB) impairment on the NVS side was observed in 7 patients. Two patients (7.1%) had large vestibular aqueduct and NVS on the same side and one patient had perilymphatic fistula.". Our comment: This a rather diverse collection of diagnoses. One wonders how many "normal" people might have NVS on delayed 3T MRI.
Of course it is possible for the labyrinth to collapse. If it can distend (from Meniere's/Hydrops), it should be able to collapse as well. This would lead one to allow for the possibilty that "parts" of the labyrinth might be moving around. For example, the utricle might be "floppy", or the geometry of the ducts of the semicircular canal might not always be aligned.
This would seem most likely to occur in conditions like Meniere's or perilymph fistula.
The association between bilateral vestibular loss and pressure sensitivity seems to us to be quite a stretch. It would seem that these authors are reporting the combination of lack of lateral canal function, and preserved something else -- perhaps utricular function. We would like to see more anatomy.
Vestibular atelectasis is obviously a possible cause of vestibular disturbance, but it remains poorly characterized as of 2020. Most papers are either case reports, unencumbered by any anatomic evidence. A recent development are papers about 3T delayed contrast MRI of the inner ear. Lots more work needs to be done here.
There does appear to be a small group of patients with both vestibular loss of their canal function, and pressure sensitivity.
- Acierno, M. D., et al. (1997). "Two types of oscillopsia in a patient with idiopathic vestibulopathy." J Neuroophthalmol 17(2): 92-94.
- Crane, B. T. (2016). "Why no Unilateral Vestibular Atelectasis?" Otol Neurotol 37(1): 115. (This is a letter to the editor, not a paper).
- Eliezer, M., et al. (2019). "Vestibular atelectasis: Myth or reality?" Laryngoscope.
- Eliezer M, Poillon G, L?vy D, Guichard JP, Toupet M, Houdart E, Atty? A, Hautefort C.Clinical and radiological characteristics of patients with collapse or fistula of the saccule as evaluated by inner ear MRI. Acta Otolaryngol. 2020 Jan 21:1-8. doi: 10.1080/00016489.2020.1713396. [Epub ahead of print]
- Finn, S., et al. (2018). "Bilateral vestibulopathy with positive Tullio phenomenon." Laryngoscope 128(5): 1223-1225.
- Kaski, D. and A. M. Bronstein (2016). "Patients with Vestibular Loss, Tullio Phenomenon, and Pressure-induced Nystagmus: Vestibular Atelectasis?" Otol Neurotol 37(1): 115-116. (this is a letter to the editor)
- Kawaguchi, S., et al. (2010). "Vestibular morphology in the German Waltzing guinea pig." J Otolaryngol Head Neck Surg 39(2): 115-121.
- Maslovara, S., et al. (2018). "Vestibular atelectasis: Decoding pressure and sound-induced nystagmus with bilateral vestibulopathy." Laryngoscope.
- Merchant, S. N. and H. F. Schuknecht (1988). "Vestibular atelectasis." Ann Otol Rhinol Laryngol 97(6 Pt 1): 565-576.
- Nadol, J. B., Jr. (1995). "Vestibular neuritis." Otolaryngol Head Neck Surg 112(1): 162-172.
- Viana, L. M., et al. (2013). "Otopathology in idiopathic Dandy's syndrome." Otol Neurotol 34(6): 1099-1103.
- Wenzel, A., et al. (2014). "Patients with vestibular loss, tullio phenomenon, and pressure-induced nystagmus: vestibular atelectasis?" Otol Neurotol 35(5): 866-872.