Clinical meaning
Meniere's disease results from endolymphatic hydrops — distension of the endolymphatic space due to impaired endolymph reabsorption by the endolymphatic sac or overproduction of endolymph. The distended scala media alters the mechanical properties of the cochlear partition, impairing frequency-selective hair cell transduction and producing fluctuating hearing loss. Episodic rupture of the distended Reissner membrane creates microperforations that allow potassium-rich endolymph to mix with sodium-rich perilymph surrounding the hair cells and afferent nerve terminals. This ionic imbalance (potassium intoxication) depolarizes and temporarily paralyzes hair cells and vestibular afferents, producing acute vertigo, hearing loss, and tinnitus. The nurse performs comprehensive vestibular assessment, manages acute episodes with pharmacological and non-pharmacological interventions, coordinates audiometric monitoring, and develops individualized patient education plans for trigger avoidance and long-term management.
Exam relevance
Risk factors: - Age 40-60 years (peak incidence) - Family history (10-15% have affected relatives) - Autoimmune inner ear disease - Allergic disease (possible endolymphatic sac inflammation) - Viral infections (herpes simplex, CMV) - Migraine (vestibular migraine shares features) - High sodium intake - Thyroid disease - Syphilis (secondary endolymphatic hydrops)