Otoliths

Head trauma, infection, certain medications, and aging are all recognized causes of otolith dislodgement. Otoliths are calcium carbonate crystals that normally reside in the utricle and enhance the sensitivity of hair cells for detecting head position relative to gravity. Each ear normally contains approximately 1,000 otolith crystals. Displaced crystals normally dissolve and are reabsorbed within approximately 20 hours in healthy endolymph with very low calcium concentration. The root problem of persistent vertigo is biochemical rather than purely mechanical. When calcium concentration in the lymph fluid is elevated, crystal dissolution slows dramatically or stops entirely and the crystals persist.