As the volume of the endolymph increases, the membranous labyrinth expands and ruptures, resulting in hearing loss and vertigo.19 The treatment is largely aimed at preventing osmotic shifts in the endolymph.
A sharpened Romberg test is performed by having the patient place the heel of one foot to the toe of the other, with arms folded and eyes closed.
Normal individuals should be able to stand in this position for longer than 30 seconds without significant sway.
Because the only objective sign of vertigo is nystagmus, examination of the eyes is extremely important in evaluating the dizzy patient.
The general physical examination is often unrewarding in the dizzy patient.
Nystagmus that is equally rapid in both directions is not vestibular in origin.
True vestibular nystagmus should also be suppressed by fixation of the gaze, convergence of the eyes, or gazing in the direction of the slow phase.
In most cases, the patient is able to localize the symptom to the involved ear because of the associated hearing-related symptoms.
In the early stages, the sensorineural hearing loss is in the low frequencies and is completely reversible, but in later stages a residual hearing loss remains and may involve both the middle and the high frequencies.
An endolymphatic mastoid shunt may be placed in the endolymphatic sac to decompress excess endolymph, or a selective sectioning of the vestibular nerve may be performed.