Possible causes of vertigo attacks in Meniere’s disease

• Published in: Medical hypotheses 2024-08, Vol.189, p.111401, Article 111401
• Main Authors: Nakashima, Tsutomu, Naganawa, Shinji, Yoshida, Tadao, Sone, Michihiko
• Format: Article
• Language: English
• Subjects: Caloric test; Endolymphatic hydrops; Heavy water; Meniere disease; Nystagmus
• ISSN: 0306-9877
• DOI: 10.1016/j.mehy.2024.111401

•Evaluation of nystagmus direction throughout vertigo attacks is critical.•Meniere’s disease elicits first-stage or two-stage nystagmus during vertigo attacks.•Trabecular meshwork has a function to keep the perilymphatic space.•Endolymphatic hydrops may enhance the vertigo attack. Various types of nystagmus during vertigo attacks in Meniere’s disease (MD) include direction-changing and non-direction-changing nystagmus. The direction-changing and non-direction-changing nystagmus may be associated with how the inner ear balance organs are influenced spatially and temporally. We hypothesized that the density difference inside the endolymph elicits the stereocilia inclination of the inner ear balance organs even if the density difference area does not directly touch the stereocilia. The direction of the nystagmus could change if the density difference area spreads around the inner ear balance organs. Numerous records of the nystagmus direction with new devices from the beginning of the nystagmus during the vertigo attacks will contribute to understanding how vertigo attacks appear in MD. The influence of the density difference may be associated with the degree of endolymphatic hydrops. Under significant endolymphatic hydrops, the volume effect due to the density difference becomes more prominent. The trabecular meshwork located in the perilymph in the superior part of the inner ear may maintain the perilymphatic space and prevent the enlargement of the endolymphatic space.