Prevalence of Endolymphatic Hydrops Herniation into the Semicircular Canals in Primary Hydropic Ear Disease:

Lisa M H de Pont1,2, Berit M Verbist2, Mark A van Buchem2

  • 1From the Department of Radiology (L.M.H.d.P., S.H.), Haga Hospital, The Hague, The Netherlands l.depont@hagaziekenhuis.nl.

Abstract

Insights

Endolymphatic hydrops (EH) herniation into the semicircular canals (SCCs) occurs in 42% of patients with hydropic ear disease (HED). This herniation, particularly in the horizontal SCC, is linked to longer disease duration and impaired vestibular function.

Area of Science:

  • Otolaryngology
  • Neuroimaging
  • Vestibular Disorders

Background:

  • Delayed postcontrast FLAIR MRI visualizes endolymphatic hydrops (EH) and semicircular canal (SCC) herniation.
  • EH herniation is associated with impaired caloric function, but its prevalence and clinical relevance are unclear.

Purpose of the Study:

  • Investigate the frequency and localization of EH herniation into the SCCs in patients with primary hydropic ear disease (HED).
  • Correlate EH herniation findings with clinical parameters, including disease severity and vestibular function.

Main Methods:

  • Retrospective study of 409 patients with MRI-confirmed primary HED.
  • Evaluated presence and location of EH herniation into SCCs.
  • Correlated findings with EH severity, vertigo, audiometry, and caloric test results.

Main Results:

  • EH herniation identified in 172 (42%) patients with primary HED.
  • Most frequent site: nonampullated limb of horizontal SCC (hSCC).
  • EH herniation associated with longer disease duration, higher EH grade, and vestibular hypofunction (P=.002) with reduced slow phase velocity (P<.001).

Conclusions:

  • EH herniation into SCCs is common in HED, predominantly in the nonampullated hSCC.
  • Herniation correlates with disease duration, EH severity, and impaired caloric function.