Approach
Risk factors
Meniere's disease (MD) usually presents in middle-aged people, with fluctuating auditory and vestibular symptoms. A family history of MD is present in up to 50% of patients. Patients with associated autoimmune disorders may have an autoimmune inner-ear disorder. These patients usually present with bilateral symptoms.[20]
History
Classic MD has the triad of vertigo, hearing loss, and tinnitus. Vertigo is unprovoked, sudden in onset, spinning in nature, and often incapacitating. It lasts minutes to hours and may be associated with nausea and vomiting.[4] Hearing loss is usually worse during acute attacks, especially in early stages of the disease. As the disease progresses, hearing loss increases in severity and may become constant. Tinnitus is described as roaring in nature and may be severe. Aural fullness is a sensation of pressure and fullness in the ear or ear discomfort and may also be present during the episode.
An atypical presentation of MD is fluctuating hearing loss and tinnitus without vertigo. This is usually referred to as cochlear hydrops, and up to 40% of patients will eventually develop vertigo.[22]
Some patients with MD complain of drop attacks, which are described as sudden loss of balance without loss of consciousness or other autonomic or neurological symptoms. The incidence varies between studies and ranges between 3% to 10% of patients.[9][23] One study reported an unusually high incidence of 72%.[24] They are more common in end-stage disease and in the older population.[23]
Bilateral disease may be present in around 30% to 50% of patients.[3][7][11]
Physical examination
Head and neck examination in patients with MD is usually normal. Horizontal and/or rotatory nystagmus that can be suppressed by visual fixation may be present. A positive Romberg's test (inability to stand with feet together and eyes closed) and an inability to walk tandem (heel-to-toe) in a straight line is often present. In the Fukuda stepping test (also known as the Unterberger test) the patient is asked to march in place with eyes closed, and may be unable to maintain position and will turn towards the affected side.
Audiology
Complete audiological evaluation is important for the diagnosis of MD and should be done in any patient presenting with hearing loss, tinnitus, vertigo, or aural fullness. Complete audiological evaluation includes pure-tone air and bone conduction with appropriate use of masking, speech audiometry, tympanometry, and oto-acoustic emissions. Hearing loss in patients with MD is typically sensorineural in nature and mainly in the low frequencies, although other configurations of hearing loss may be present. Usually, low-frequency hearing loss is present in the early stages of MD and during or before attacks. As the disease progresses, middle and high frequencies are affected. There may be a disproportionate drop in word score recognition in comparison with pure-tone findings. Serial audiological evaluation might show fluctuation in the hearing, which at times is helpful in making the diagnosis in patients with MD.
Once the diagnosis of MD is suspected, electrocochleography (ECochG) may be helpful. ECochG is a technique for recording the electrical events of the cochlea. The clinical application is confined to the stimulus-related cochlear potentials and usually includes measurement of the entire nerve or compound action potential of the auditory nerve. An ECochG consists of a cochlear microphonic and measures the cochlear summating potential and the action potential, independently or in combination. Broad-band clicks or tonal stimuli are used to evoke the components of interest.[25][26][27][28][29] ECochG should not be used when the pure-tone average for frequencies 1000-4000 Hz reaches or exceeds 50 dB HL. It does have value in the early stages of the disease when symptoms are present but audiometry is normal.[30] Once hearing is affected, the best serial test is pure-tone audiometry in the affected ear or ears. However, it is the author's opinion that the test should be performed at low frequencies down to 125 Hz.
Vestibular testing using electronystagmography or videonystagmography is performed routinely in patients presenting with vertigo, dizziness, or loss of balance. Rotatory chair or vestibular-evoked myogenic potentials are not available in all centres, but may be helpful in the diagnosis of MD. Vestibular testing may not be possible during or shortly after acute attacks.
Other investigations
Any patients with asymmetry of hearing should have magnetic resonance imaging (MRI) with gadolinium to exclude a retro-cochlear cause of hearing loss, such as acoustic neuroma.
3-D MRI protocols have been developed to delineate endolymphatic hydrops, but they are still in the investigational stages.[31] MRI, after both intravenous and intratympanic injection of gadolinium, is being studied.[32][33][34]
Patients with MD who have bilateral symptoms and do not respond to conventional therapy should be tested for autoimmune disorders. This may include anti-nuclear antibody, anti-neutrophil cytoplasmic antibody, and rheumatoid factor.[35]
Patients with an acute or recent decrease in hearing should be assessed for hypothyroidism, Lyme disease, and syphilis.
Use of this content is subject to our disclaimer