EH, in turn, is strongly associated with developing MD, but not everyone with EH develops MD: "The relationship between endolymphatic hydrops and Menieres disease is not a simple, ideal correlation. "Additionally, in fully developed MD, the balance system (vestibular system) and the hearing system (cochlea) of the inner ear are affected, but some cases occur where EH affects only one of the two systems enough to cause symptoms. The corresponding subtypes of MD are called vestibular MD, showing symptoms of vertigo, and cochlear MD, showing symptoms of hearing loss and tinnitus.The mechanism of MD is not fully explained by EH, but fully developed EH may mechanically and chemically interfere with the sensory cells for balance and hearing, which can lead to temporary dysfunction and even to death of the sensory cells, which in turn can cause the typical symptoms of MD – vertigo, hearing loss, and tinnitus.
Physical therapy
While use of physical therapy early after the onset of MD is probably not useful due to the fluctuating disease course, physical therapy to help retraining of the balance system appears to be useful to reduce both subjective and objective deficits in balance over the longer term. Counseling
The psychological distress caused by the vertigo and hearing loss may worsen the condition in some people. Counseling may be useful to manage the distress, as may education and relaxation techniques. Surgery
If symptoms do not improve with typical treatment, surgery may be considered. Surgery to decompress the endolymphatic sac is one option. A systematic review in 2015 found that three methods of decompression have been used – simple decompression, insertion of a shunt, and removal of the sac. It found some evidence that all three methods were useful for reducing dizziness, but that the level of evidence was low, as trials were not blinded nor were placebo controls used.Another 2015 review found that, on autopsy, shunts used in these surgeries often turn out to be displaced or misplaced, and recommended their use only in cases where the condition is uncontrolled and affecting both ears. A systematic review from 2014 found that in at least 75% of people, EL sac decompression was effective at controlling vertigo in the short term (>1 year of follow-up) and long term (>24 months).An estimated 30% of people with MD have Eustachian tube dysfunction.