Conclusion: Profound deafness (PD) is unlikely to be the only cause of endolymphatic hydrops (EH) in patients with delayed endolymphatic hydrops (DEH). Further studies in large patient cohorts are required to determine the etiologic co-factors involved in the development of EH in patients with PD and DEH.
Objectives: DEH usually occurs in patients with sustained unilateral PD who then develop episodic vertigo or fluctuating hearing loss. The latency can vary markedly between PD and development of DEH, but the factors affecting inner ear homeostasis and causing EH during this latency period remain unclear. The study aimed to assess the differences in EH and functional status of the inner ear between patients with PD only and those with DEH.
Method: Two PD and 10 DEH patients who had developed PD in early childhood were enrolled. Gadolinium-enhanced magnetic resonance imaging of the inner ear was performed in all patients to assess the degree of EH in the vestibule and cochlea.
Results: There was no evidence of EH in the affected ears of patients with PD alone. DEH patients, however, showed significant EH in either the cochlea or vestibule, suggesting that EH development and DEH onset were strongly correlated.
Keywords: Delayed endolymphatic hydrops; endolymphatic hydrops; gadolinium-enhanced inner ear MRI; plasma antidiuretic stress hormone vasopressin; profound deafness.