A cure for benign positional vertigo.
Benign positional vertigo is a common clinical entity encountered in any dizzy clinic. It is easily diagnosed on the basis of historical information and a positive Dix-Hallpike position test. The available evidence suggests that this condition is due to involvement of the posterior semicircular canal. The pathophysiology of this condition can be explained theoretically on the basis of free-floating particles within the endolymph of the posterior semicircular canal that move under the influence of gravity with certain provocative positional changes. Based on this theoretical model, a variety of particle-repositioning manoeuvres have been developed that attempt to relocate the loose particles from the posterior semicircular canal to the utricular sac. If the particles are kept in the utricular sac for a period of 48 h by maintaining the patient in an upright position, the clinical symptoms are relieved in a high proportion of patients. If the manoeuvre is unsuccessful on a first attempt, or if the benign positional vertigo recurs at a later date, the condition can usually be relieved by a second manoeuvre. Bilateral benign positional vertigo can be treated by performing a manoeuvre on one side followed by a manoeuvre on the other side at a later date. On occasion, posterior canal benign positional vertigo is converted to horizontal canal benign positional vertigo, but this subsides readily within the 48-h post-manoeuvre period.